SlideShare a Scribd company logo
1 of 28
* of 33
© Boardworks Ltd 2008
*
Boardworks AS Biology
Circulation and Blood
* of 33
© Boardworks Ltd 2008
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
In ‘Slide Show’ mode, click the name of a section to jump
straight to that slide.
* of 33
© Boardworks Ltd 2008
Why need a transport system?
Single-celled organisms, such as bacteria and amoeba (below),
can obtain nutrients and excrete waste simply by diffusion.
nutrients
waste products
Multi-cellular organisms, such as insects, fish and mammals,
require a more specialized transport system. Why is this?
*
Boardworks AS Biology
Circulation and Blood
* of 33
© Boardworks Ltd 2008
Surface area to volume ratio
In larger organisms, diffusion of substances would occur far too
slowly to enable them to survive: the rate of diffusion increases
with the square of the distance it has to travel.
Single-celled organisms have a very large surface area to
volume ratio, because the diffusion path is so short.
This is not just because of its size, however: more important is
an organism’s surface area to volume ratio.
*
Boardworks AS Biology
Circulation and Blood
Photo credit: Jupiterimages Corporation
Teacher notes
Flatworms have no specialized transport system but rely on
diffusion to distribute oxygen, nutrients and waste products.
Students could be asked to state why they think flatworms are
able to survive without a transport system.
* of 33
© Boardworks Ltd 2008
Surface area and volume
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
This activity can be used by students to compare the
relationship between surface area and volume between different
types of shape, e.g. flat rectangles vs. cubes. Students could
plot a graph to follow the trends.
29.unknown
* of 33
© Boardworks Ltd 2008
Components of circulatory systems
Multi-cellular animals overcome the limitations of diffusion by
having a specialized circulatory system. This comprises:a
heartvessels through which the fluid can flow.a fluid in which
substances are transported
The two types of circulatory system are open (e.g. molluscs,
arthropods) and closed (e.g. vertebrates, a few invertebrates).
*
Boardworks AS Biology
Circulation and Blood
Photo credit: Jupiterimages Corporation
* of 33
© Boardworks Ltd 2008
Open circulatory systems
An open circulatory system consists of a heart that pumps a
fluid called haemolymph through short vessels and into a large
cavity called the haemocoel.
When the heart relaxes, the haemolymph blood is sucked back
in via pores called ostia.
Haemolymph moves around the haemocoel due to the movement
of the organism.
heart
haemocoel
In the haemocoel, the haemolymph directly bathes organs and
tissues, enabling the diffusion of substances.
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Cephalopod molluscs (octopus, squid and nautilus) have a
closed circulatory system.
* of 33
© Boardworks Ltd 2008
Closed circulatory systems
In a closed circulatory system, blood is fully enclosed within
blood vessels at all times.
From the heart, blood is pumped through a series of
progressively smaller vessels. In the smallest vessels,
capillaries, substances diffuse in and out of the blood and into
cells.
Blood then returns to the heart via a series of progressively
larger vessels.
heart
capillaries
*
Boardworks AS Biology
Circulation and Blood
* of 33
© Boardworks Ltd 2008
Closed circulatory systems
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Students could be asked to list possible advantages a double
circulatory system has over single circulatory systems. A major
advantage is that the second pass through the heart gives the
blood a boost, increasing it’s rate of flow and enabling oxygen
and nutrients to be delivered more quickly to cells. This enables
birds/mammals to have a higher metabolic rate than fish.
In a double circulatory system, the pulmonary circulation
transports blood between the heart and the lungs, whereas the
systemic circulation transports blood between the heart and the
rest of the body.
Amphibians have a double circulatory system but with a three-
chambered heart. Students could be asked to sketch what the
structure of an amphibian heart might look like.
See ‘The Heart’ presentation for more information about the
structure of the heart.
38.unknown
* of 33
© Boardworks Ltd 2008
The mammalian circulatory system
*
Boardworks AS Biology
Circulation and Blood
41.unknown
* of 33
© Boardworks Ltd 2008
Circulation: true or false?
44.unknown
* of 33
© Boardworks Ltd 2008
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
In ‘Slide Show’ mode, click the name of a section to jump
straight to that slide.
* of 33
© Boardworks Ltd 2008
Guide to blood vessels
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
As blood at high pressure enters the artery it expands to lower
the pressure. As blood at low pressure enters the artery it
recoils to maintain the pressure.
The further away from the heart, the less elastic tissue and more
smooth muscle an the artery is the less elastic tissue it has and
the more smooth muscle. This is because the blood further away
from the heart is at a lower pressure.
47.unknown
* of 33
© Boardworks Ltd 2008
Identifying blood vessels
*
Boardworks AS Biology
Circulation and Blood
Photo credit: Karen Hart, Peninsula College
http://www.pc.ctc.edu/hart/index.html
50.unknown
* of 33
© Boardworks Ltd 2008
Blood flow in veins
*
Boardworks AS Biology
Circulation and Blood
53.unknown
* of 33
© Boardworks Ltd 2008
Varicose veins
If a vein wall becomes weakened, valves may no longer close
properly. This allows backflow of blood, causing the vein to
become enlarged and bumpy, and become varicose.
This usually happens in superficial veins, near the skin surface
in the lower legs, as opposed to deep veins, which lie
underneath muscles.
Varicose veins can be surgically removed without affecting
blood flow, as most blood is returned to the heart by deep veins.
*
Boardworks AS Biology
Circulation and Blood
* of 33
© Boardworks Ltd 2008
Maintaining high blood pressure
Blood pressure is the main force that drives blood from the
heart around the body.During systole (heart contraction), blood
is pumped through the aorta and other arteries at high pressure.
The elastic fibres of arteries enable them to expand and allow
blood through.During diastole (heart relaxation), the blood
pressure in the arteries drops. The elastic recoil of the artery
walls help force the blood on.
As blood moves through smaller arterioles into capillaries, and
then into venules and veins, its velocity and pressure drop
continuously.
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Students could be asked to draw a line graph of how they think
blood pressure varies as it moves through the aorta, arteries,
arterioles, capillaries, venules and veins.
See the ‘The Heart’ presentation for more information about
systole and diastole.
* of 33
© Boardworks Ltd 2008
Arteries, capillaries and veins
60.unknown
* of 33
© Boardworks Ltd 2008
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
In ‘Slide Show’ mode, click the name of a section to jump
straight to that slide.
* of 33
© Boardworks Ltd 2008
What is blood?
Blood is a specialized transport medium that is also considered
a special type of connective tissue. An average adult has 4–6
litres of blood.
Blood has a range of functions such as:transportdefence
thermoregulationmaintaining pH of body fluids.
*
Boardworks AS Biology
Circulation and Blood
Photo credit: National Cancer Institute / Science Photo Library
Coloured scanning electron micrograph (SEM) of human blood
showing red and white cells and platelets. Red blood cells
(erythrocytes) have a characteristic biconcave- disc shape and
are numerous. These large cells contain haemogl obin, a red
pigment by which oxygen is transported around the body. They
are more numerous than white blood cells (yellow). White blood
cells (leucocytes) are rounded cells with microvilli projections
from the cell surface. Leucocytes play an important rol e in the
immune response of the body. Platelets are smaller cells (pink)
that play a major role in blood clotting.
Teacher notes
Blood, along with bone and cartilage, is considered a type of
connective tissue, even though it is quite different to other
connective tissues, such as collagen. Embryologically, it has the
same origin as other connective tissues, and could be said to
connect other body tissues together through the transport of
substances.
* of 33
© Boardworks Ltd 2008
The composition of blood
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
The amount of blood occupied by erythrocytes is called the
haematocrit. An athlete’s haematocrit is used in drug testing -
an elevated level may indicate the athlete has artificially
boosted the number of erythrocytes by using the drug
erythropoietin, or by ‘blood doping’ - transfusing erythrocytes,
either their own (which have been previously harvested and
stored) or from a compatible donor.
Only about 2% of all the oxygen in blood is transported in the
plasma. The vast majority is bound to haemoglobin in
erythrocytes. In contrast, most carbon dioxide is transported in
the plasma.
See the ‘Gas Exchange’ presentation for more information about
haemoglobin and the transport of oxygen.
See the ‘Immunology’ presentation for more information about
leukocytes.
65.unknown
* of 33
© Boardworks Ltd 2008
Features of erythrocytes
What are the specialized features of an erythrocyte?
flattened, biconcave disc shape: ensures large surface area to
volume ratio for efficient gas exchange
diameter (6–8 µm) larger than capillary diameter: slows blood
flow to enable diffusion of oxygen
no nucleus or organelles: maximises space for haemoglobin, so
more oxygen can be transported
large amount of haemoglobin: for transporting oxygen
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Only the erythrocytes of mammals and a few other vertebrates
have no nucleus. They are present in the erythrocytes of most
other vertebrates. The lack of nucleus means erythrocytes
cannot divide so most be continuously replaced by new cells
produced in the bone marrow. Human erythrocytes live for
about 120 days.
Haemoglobin makes up about 97% of the dry mass of an
erythrocyte.
See the ‘Gas Exchange’ presentation for more information about
haemoglobin.
* of 33
© Boardworks Ltd 2008
Blood clotting
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Serum is plasma from which fibrinogen has been removed,
therefore preventing it from clotting. Serum is used to treat
plasma loss in people with severe burns (loss of outer layer of
skin means tissue fluid, but not blood cells, are rapidly lost).
70.unknown
* of 33
© Boardworks Ltd 2008
Substances in blood clotting
*
Boardworks AS Biology
Circulation and Blood
73.unknown
* of 33
© Boardworks Ltd 2008
Plasma proteins and blood pressure
About 8% of blood plasma consists of plasma proteins, of which
about half may be albumins.
The balance between the hydrostatic pressure of blood (‘blood
pressure’) and the osmotic pressure of blood is important in the
formation of tissue fluid.
These are a group of small proteins involved in the transport of
other substances (e.g. fatty acids, hormones) and which help
regulate the osmotic pressure of blood.
*
Boardworks AS Biology
Circulation and Blood
Photo credit: Borislav Mitev
Human serum albumin, to which six molecules of palmitic acid
(grey) are bound.
Teacher notes
See the ‘Transport Across Membranes’ presentation for more
information about osmosis.
* of 33
© Boardworks Ltd 2008
Formation of tissue fluid
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
One sign of high blood pressure is oedema – swelling caused by
the accumulation of tissue fluid. Students could be asked to
explain how this occurs in terms of blood pressure and osmotic
pressure.
78.unknown
* of 33
© Boardworks Ltd 2008
Lymph
Not all tissue fluid returns to the capillaries. The excess drains
into the lymphatic system, where it forms lymph.
Lymph is a colourless/pale yellow fluid similar to tissue fluid
but containing more lipids.
The lymphatic system drains into the circulatory system near
the vena cavae via the thoracic duct.
lymphatic capillaries
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Lymph contains fatty substances because digested lipids are
transported from the digestive system via the lymphatic system
before being returned to the circulatory system.
* of 33
© Boardworks Ltd 2008
The lymphatic system
The lymphatic system is a secondary circulatory system and a
major part of the immune system. It consists of:lymphatic
capillaries and vein-like lymph vessels, containing valveslymph
nodes – sac-like organs that trap pathogens and foreign
substances, and which contain large numbers of white blood
cellslymphatic tissue in the spleen, thymus and tonsils – these
also contain large amounts of white blood cells and are involved
in their development.
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
Lymph moves through the lymphatic system via the action of
skeletal muscles and the use of valves to prevent backflow.
Lymphatic tissues and lymph nodes are the site of development
and maturation of lymphocytes.
Lymphatic filariasis is a parasitic disease caused when thread-
like nematode worms (transmitted by mosquitoes) become
lodged in the lymphatic system. In extreme cases, this causes
elephantiasis – a swelling and thickening of skin and underlying
tissue, usually in the legs or genitals.
* of 33
© Boardworks Ltd 2008
Composition of body fluids
*
Boardworks AS Biology
Circulation and Blood
85.unknown
* of 33
© Boardworks Ltd 2008
*
Boardworks AS Biology
Circulation and Blood
Teacher notes
In ‘Slide Show’ mode, click the name of a section to jump
straight to that slide.
* of 33
© Boardworks Ltd 2008
Glossary
*
Boardworks AS Biology
Circulation and Blood
88.unknown
* of 33
© Boardworks Ltd 2008
What’s the keyword?
*
Boardworks AS Biology
Circulation and Blood
91.unknown
* of 33
© Boardworks Ltd 2008
Multiple-choice quiz
*
Boardworks AS Biology
Circulation and Blood
94.unknown
The Lamentations of Khakheperre-sonbe1
Introduction (Simpson, 211)
“The author of our lamentations … describes the plight of a
disorganized land in a time of troubles … [and]
a discourse with the man’s other self. … The text is written on
both sides of a writing board of Dynasty 18 [c. 1543–
1292 BC] in the British Museum (EA 5645). It was probably
composed in the Middle Kingdom [c. 2061–1690 BC]
or the Second Intermediate Period [c. 1674-1549 BC]. The last
line in the text is complete but lacks any indication
that it represents the end of the composition. Perhaps the
composition was continued on another tablet.”
Introduction (Erman, 108)2
“As is evident from his name, Khakhepperre-sonbu
(“Khekheperre is in health”), the author lived under
King Sesostris II, i.e. about 1900 B.C. As the text is written on
the writing-board of a school-boy of the Eighteenth
Dynasty, it was evidently regarded at that time also as a
classical work. … the author expresses a desire to discover
new and unheard-of utterances, with which to ador n his
complaint. The book is in the form of the colloquy3 of a
man with his own heart as his only true friend. … We know
nothing, apart from this work, about the calamity which
the writer deplores, though, to be sure, in view of our
inadequate knowledge of Egyptian history, we cannot exactly
be surprised at this.”
Introduction (Lichtheim, 145)4
“… The single preserved copy was dated by Gardiner to the
middle of the Eighteenth Dynasty, while the
work itself clearly belongs to the Middle Kingdom. In fact, it
can be dated with some assurance to the reign of
Sesostris II or shortly after …. If a political criticism was
intended, it is concealed behind the generalized metaphors
on the theme of anarchy and distress. … the laments on the
"distress of the land" are metaphors. They are either
purely literary, designed to enlarge the literary possibilities of
the theme, or they may have conveyed a covert
political criticism, of a kind that could not be made openly and
hence was wrapped in metaphor. … the author
addresses his plaints to his heart, a device that further enhances
the rhetorical character of the work. The text
consists of fourteen lines on the recto and six lines on the verso;
and the lines are grouped into four sections by
means of short dividers. As written on the board, the text is
complete, for after the fourth section there are two lines
in a larger handwriting which are not connected with it. The
text, however, may be the first part of a lost longer
work."
RECTO5
The gathering6 together of sayings, the culling of phrases, the
search for words by an
inquisitive mind7, which the wab-priest8 of Heliopolis9, Seny’s
son Khakheperre-sonbe who is
called Ankhu, wrote.
He said: Would that I had unknown speeches, erudite phrases in
new language10 which
has not yet been used, free from (the usual) repetitions, not the
phrases of past speech which
(our) forefathers spoke. I shall drain myself11 for something in
it in giving free rein to all I shall
1 Simpson, William Kelly (ed.). The Literature of Ancient
Egypt (3rd ed.). New Haven, CT: Yale University Press, 2003.
2 Erman, Adolf (ed.), The Ancient Egyptians. New York:
Harper & Row, Publishers: 1966 [a revised translation of the
1923 original book in German; includes an introduction by
William K. Simpson].
3 “a conversational exchange; dialogue” (dictionary.com).
4 Lichtheim, Ancient Egyptian Literature, vol 1: The Old and
Middle Kingdoms. University of California Press, 1973.
5 “a right-hand page of an open book or manuscript; the front of
a leaf” (dictionary.com).
6 “He thinks of himself as plucking flowers” (Erman, 108, fn
4). “the heaping of sayings” (Lichtheim, 146).
7 “heart” (Erman and Lichtheim)
8 “… the duty of this priest was to pour out the drink-offering
… [and] to examine into the purity of the sacrificial
animals” (Erman, A. Life in Ancient Egypt. H.M. Tirard
(trans.), New York: Dover Publications, Inc., 1971. Reprint of
1894 original).
9 The town of “On” (as in the Bible).
10 “Novel, untried words” (Lichtheim, 146).
11 “I wring out my body” (Erman, 109). “The body is accounted
the seat of the thoughts” (Erman, 109, fn 1). “I
wring out my body of what it holds/ In releasing all my words”
(Lichtheim, 146).
say. For indeed whatever has been said has been repeated, while
what has (once) been said has
been said. There should be no boasting about the literature of
the men of former times or what
their descendants discovered12!
The speaker has not (yet) spoken. One who will speak now
speaks13. What another has
found will be said. Not a tale of telling after the fact: they did it
before. Not yet a story for future
telling. Such is seeking disaster. It is falsehood. And there is no
one who shall recall such a
man’s name to the people.
I have said these things just as I have seen, beginning with the
first generation down to
those who shall come afterward, when they (too) shall imitate
the past.14
Would that I might know what others did not know15, even
what has not yet been
repeated, that I might know what others did not know, even
what has not yet been repeated, that I
might speak and my heart answer me, that I might enlighten my
grief to it, and that I might thrust
onto it the weight which is on my back16, (and speak) thoughts
about what afflicts me, that I
might express to it what I suffer through it, that I might speak,
Yea, about my feelings17!
I am thinking about what has happened18, the things that have
come to pass throughout
the land. Changes are taking place. It is not like last year; one
year is more troublesome19 than
the next. The land is in chaos, has become my destruction, has
been made into a state of unrest20.
Justice has been cast out, and evil is inside the shrine21. The
designs of the gods are
disturbed, and their perquisites22 are passed over. The land is
in dire state. Mourning is
everywhere. Towns and districts are in lamentation. All alike
are grief stricken. The back is
turned on anything of worth23; the tranquil are distressed.
Troubles occur daily, and the face
shrinks from what is about to happen.
I will say my say about it; for my limbs are heavy laden24. I
am distressed in my heart,
and it is painful25 to hide my thoughts about it. Although
another heart would break, a stout heart
in a difficult situation is the companion of its master.
12 “found” (Lichteim, 146); "Gmi [Ancient Egyptian word],
'find,' here and below in line 5, in the pregnant sense of
'find useful,' 'make use of'" (Lichteim, 148, fn 1).
13 “Not speaks one who spoke/Then speaks one who will speak”
(Lichtheim, 146).
14 “No one is original; the ‘first generation’ is of course merely
a manner of speech” (Erman, 109, fn 3). "It is
interesting that imitation of the past, which is usually
recommended in the [Ancient Eygptian genre of]
Instructions, is here rejected" (Lichtheim, 148, fn 2).
15 “Would that I know what others ignore” (Lichtheim, 147).
16 “Shift to it the load on my back” (Lichtheim, 147).
17 “And sigh ‘Ah’ with relief” (Lichtheim, 147).
18 “Here begins the prallell text of the ostracon” (Simpson,
212) [ostracon: “a potsherd” (dictionary.com). These
broken pieces of pottery were used for writing practice in
Egyptian schools.]
19 “Irksome” (Lichtheim, 147).
20 “The land breaks up, is destroyed/Becomes [a wasteland]”
(Lichtheim, 147).
21 “Order is cast out/Chaos is in the council hall” (Lichtheim,
147); "… the pair is maat [“order,” here “justice”] and
isfet [“chaos,” here “evil”]" (Lichteim, 148, fn 3). These are
central terms in the Ancient Egyptian understanding
of the universe.
22 “something demanded or due as a particular privilege”
(dictionary.com). Erman translates this sentence as, “The
plans of the gods are destroyed and their ordinances
transgressed” (109).
23 “The back is turned upon respect” (Erman, 109); “one turns
one’s back on dignity” (Lichtheim, 147).
24 “He would fain complain of his misery, for it is painful to
hide it in the body” (Erman, 109). “The lords of silence
are disturbed” (Lichtheim, 147).
25 "whd [Ancient Egyptian word] occurs four times, varying
from 'painful' to 'suffer,' and 'endure' (I, 13-4, and II, 4-
5)" (Lichtheim, 149, fn 5).
O would that I had a heart that knew how to suffer. Then I
might alight, and I would load
it with phrases of misery, and I might drive off to it my
suffering26.
VERSO27
He said to his heart: Come now, my heart, that I may converse
with you and you may
answer me my sayings, that you may interpret for me that which
is throughout the land28, for
those who were radiant (in white garments) have been cast
down.29
I am thinking30 about what has taken place. Misery is ushered
in today. By the morning
the strangers have (still) not passed away31. Everyone is silent
about it. The entire land is in a
serious plight32, and there is nobody free from wrong: all
people alike do it. Hearts are
dejected33. The one who gives commands is (now) one to whom
commands are given, and the
hearts of both are quieted34.
One rises to these things daily, and hearts have not thrust them
aside35. Yesterday’s state
is like today’s, because of the passing by of many things. The
countenance is perplexed. There is
no man wise enough to know it, and there is no man angry
enough to speak out. Every day one
wakes to suffering.
Long and burdensome is my suffering. There is not strength for
the wretched to rescue
him from one stronger than him36. Silence about what is heard
is painful. It is miserable to have
to give an answer to the ignorant37. To oppose a speech makes
for disaffection. The heart cannot
accept truth. A reply to a speech is insufferable38. All a man
wants is his own talk. Everyone is
based in crookedness. Precision in speech39 is abandoned.
I speak to you, my heart, that you may answer me. Yet a heart
which is appealed to
cannot be silent. The needs of a servant40 are like those of a
master41. Plentiful (now) are the
things which weigh upon you42.
26 “Then I would rest upon it that I might load it with words of
misery, that I might drive to it my pain” (Erman,
110).
27 “a left-hand page of an open book or manuscript”
(dictionary.com)
28 “expound to me the things that are throughout the land, that
are bright and lie outstretched” (Erman, 110)
29 “What is in view of all, yet is comprehended of none”
(Erman, 110, fn 1).”those who shone are overthrown”
(Lichtheim, 148); "the great man is overthrown" (Lichtheim,
149, fn 6).
30 “I meditate” (Lichtheim, 148).
31 “And turmoil will not cease tomorrow” (Lichtheim, 148).
32 “The whole land is in a great condition” (Erman, 110);
“’Condition’ for ‘bad condition’” (Erman, 110, fn 2).
33 "… probably 'greedy' rather than 'sad' [here, ‘dejected’]"
(Lichtheim, 149, fn 8).
34 “both submit” (Lichtheim, 148).
35 “Everyday men rise up early thereto” (Erman, 110). “One
wakes to it everyday,/And the hearts do not reject it”
(Lichtheim, 148).
36 “The sufferer lacks strength to save himself/From that which
overwhelms him” (Lichtheim, 147).
37 “The meaning of the passage probably is: It is not right, my
heart, that you answer me nothing, and wherefore
whould I speak to you, if you wish to know nothing about it?”
(Erman, 110, fn 3). "… the sense is 'lacking,
deficient'; hence 'futile' seems appropriate here" (Lichtheim,
149, fn 10).
38 “one cannot bear a statement of fact” (Lichtheim, 148).
39 “Right-speaking” (Lichtheim, 148).
40 “The servant is the heart, which also suffers, if the man, its
master, suffers” (Erman, 110, fn 4).
41 “Lo, servant and master fare alike” (Lichtheim, 148).
42 “The tablet ends here and perhaps the text as well”
(Simpson, 213).

More Related Content

Similar to of 33© Boardworks Ltd 2008Boardworks AS Biolo

Circulatory system
Circulatory systemCirculatory system
Circulatory system
nike500
 
13 fluid flow 2010
13 fluid flow 201013 fluid flow 2010
13 fluid flow 2010
setherin
 
Red Blood Cell
Red Blood CellRed Blood Cell
Red Blood Cell
Bong Tong
 

Similar to of 33© Boardworks Ltd 2008Boardworks AS Biolo (20)

digital text correct.pptx
digital text correct.pptxdigital text correct.pptx
digital text correct.pptx
 
Circulatory system
Circulatory systemCirculatory system
Circulatory system
 
Body fluid and circulation
Body fluid and circulationBody fluid and circulation
Body fluid and circulation
 
Pa 7
Pa 7Pa 7
Pa 7
 
Q & A. on Physiology for Exam 17november13
Q & A.  on  Physiology for Exam 17november13Q & A.  on  Physiology for Exam 17november13
Q & A. on Physiology for Exam 17november13
 
CIRCULATORY SYSTEM
CIRCULATORY SYSTEMCIRCULATORY SYSTEM
CIRCULATORY SYSTEM
 
insect circulatory and excretory systems
insect circulatory and excretory systemsinsect circulatory and excretory systems
insect circulatory and excretory systems
 
13 fluid flow 2010
13 fluid flow 201013 fluid flow 2010
13 fluid flow 2010
 
Red Blood Cell
Red Blood CellRed Blood Cell
Red Blood Cell
 
CLASS 11 TH Body fluids and circulation
 CLASS 11 TH Body fluids and circulation CLASS 11 TH Body fluids and circulation
CLASS 11 TH Body fluids and circulation
 
11 Circulatory Systems I PPT.pdf
11 Circulatory Systems I PPT.pdf11 Circulatory Systems I PPT.pdf
11 Circulatory Systems I PPT.pdf
 
11 Circulatory Systems I PPT.pdf
11 Circulatory Systems I PPT.pdf11 Circulatory Systems I PPT.pdf
11 Circulatory Systems I PPT.pdf
 
Fish Circulatory System by uzma nihar
Fish Circulatory System by uzma niharFish Circulatory System by uzma nihar
Fish Circulatory System by uzma nihar
 
Class 11 project biology prect topic body fluid and circulation
Class 11 project biology prect topic body fluid and circulationClass 11 project biology prect topic body fluid and circulation
Class 11 project biology prect topic body fluid and circulation
 
Circulation
CirculationCirculation
Circulation
 
Chapter 12
Chapter 12Chapter 12
Chapter 12
 
Chapter 12
Chapter 12Chapter 12
Chapter 12
 
Chapter 20 Blood Circulatory System
Chapter 20 Blood Circulatory System Chapter 20 Blood Circulatory System
Chapter 20 Blood Circulatory System
 
Ch 32 & 33 lecture
Ch 32 & 33 lectureCh 32 & 33 lecture
Ch 32 & 33 lecture
 
Biology blog
Biology blogBiology blog
Biology blog
 

More from TatianaMajor22

Please readRobert Geraci, Russia Minorities and Empire,” in .docx
Please readRobert Geraci, Russia Minorities and Empire,” in .docxPlease readRobert Geraci, Russia Minorities and Empire,” in .docx
Please readRobert Geraci, Russia Minorities and Empire,” in .docx
TatianaMajor22
 
Ford VS ChevroletThere are many reasons that make the Chevy.docx
Ford VS ChevroletThere are many reasons that make the Chevy.docxFord VS ChevroletThere are many reasons that make the Chevy.docx
Ford VS ChevroletThere are many reasons that make the Chevy.docx
TatianaMajor22
 
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docxAppendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
TatianaMajor22
 
Effects of StressProvide a 1-page description of a stressful .docx
Effects of StressProvide a 1-page description of a stressful .docxEffects of StressProvide a 1-page description of a stressful .docx
Effects of StressProvide a 1-page description of a stressful .docx
TatianaMajor22
 
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docxDesign Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
TatianaMajor22
 
Question 12.5 pointsSaveThe OSU studies concluded that le.docx
Question 12.5 pointsSaveThe OSU studies concluded that le.docxQuestion 12.5 pointsSaveThe OSU studies concluded that le.docx
Question 12.5 pointsSaveThe OSU studies concluded that le.docx
TatianaMajor22
 
Case Study 1 Questions1.     What is the allocated budget .docx
Case Study 1 Questions1.     What is the allocated budget  .docxCase Study 1 Questions1.     What is the allocated budget  .docx
Case Study 1 Questions1.     What is the allocated budget .docx
TatianaMajor22
 
Behavior in OrganizationsIntercultural Communications Exercise .docx
Behavior in OrganizationsIntercultural Communications Exercise .docxBehavior in OrganizationsIntercultural Communications Exercise .docx
Behavior in OrganizationsIntercultural Communications Exercise .docx
TatianaMajor22
 
Discussion Question Comparison of Theories on Anxiety Disord.docx
Discussion Question Comparison of Theories on Anxiety Disord.docxDiscussion Question Comparison of Theories on Anxiety Disord.docx
Discussion Question Comparison of Theories on Anxiety Disord.docx
TatianaMajor22
 
I have always liked Dustin Hoffmans style of acting, in this mov.docx
I have always liked Dustin Hoffmans style of acting, in this mov.docxI have always liked Dustin Hoffmans style of acting, in this mov.docx
I have always liked Dustin Hoffmans style of acting, in this mov.docx
TatianaMajor22
 
If you are using the Blackboard Mobile Learn IOS App, please clic.docx
If you are using the Blackboard Mobile Learn IOS App, please clic.docxIf you are using the Blackboard Mobile Learn IOS App, please clic.docx
If you are using the Blackboard Mobile Learn IOS App, please clic.docx
TatianaMajor22
 
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docxMATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
TatianaMajor22
 
If the CIO is to be valued as a strategic actor, how can he bring.docx
If the CIO is to be valued as a strategic actor, how can he bring.docxIf the CIO is to be valued as a strategic actor, how can he bring.docx
If the CIO is to be valued as a strategic actor, how can he bring.docx
TatianaMajor22
 
I am showing below the proof of breakeven, which is fixed costs .docx
I am showing below the proof of breakeven, which is fixed costs .docxI am showing below the proof of breakeven, which is fixed costs .docx
I am showing below the proof of breakeven, which is fixed costs .docx
TatianaMajor22
 
Karimi 1 Big Picture Blog Post ​ First Draft College .docx
Karimi 1 Big Picture Blog Post ​ First Draft College .docxKarimi 1 Big Picture Blog Post ​ First Draft College .docx
Karimi 1 Big Picture Blog Post ​ First Draft College .docx
TatianaMajor22
 
Please try not to use hard words Thank youWeek 3Individual.docx
Please try not to use hard words Thank youWeek 3Individual.docxPlease try not to use hard words Thank youWeek 3Individual.docx
Please try not to use hard words Thank youWeek 3Individual.docx
TatianaMajor22
 

More from TatianaMajor22 (20)

Please readRobert Geraci, Russia Minorities and Empire,” in .docx
Please readRobert Geraci, Russia Minorities and Empire,” in .docxPlease readRobert Geraci, Russia Minorities and Empire,” in .docx
Please readRobert Geraci, Russia Minorities and Empire,” in .docx
 
Ford VS ChevroletThere are many reasons that make the Chevy.docx
Ford VS ChevroletThere are many reasons that make the Chevy.docxFord VS ChevroletThere are many reasons that make the Chevy.docx
Ford VS ChevroletThere are many reasons that make the Chevy.docx
 
Fairness and Discipline     Weve all been disciplined at one.docx
Fairness and Discipline     Weve all been disciplined at one.docxFairness and Discipline     Weve all been disciplined at one.docx
Fairness and Discipline     Weve all been disciplined at one.docx
 
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docxAppendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
Appendix 12A Statement of Cash Flows—Direct MethodLEARNING .docx
 
Effects of StressProvide a 1-page description of a stressful .docx
Effects of StressProvide a 1-page description of a stressful .docxEffects of StressProvide a 1-page description of a stressful .docx
Effects of StressProvide a 1-page description of a stressful .docx
 
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docxDesign Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
Design Factors NotesCIO’s Office 5 People IT Chief’s Offi.docx
 
Question 12.5 pointsSaveThe OSU studies concluded that le.docx
Question 12.5 pointsSaveThe OSU studies concluded that le.docxQuestion 12.5 pointsSaveThe OSU studies concluded that le.docx
Question 12.5 pointsSaveThe OSU studies concluded that le.docx
 
Case Study 1 Questions1.     What is the allocated budget .docx
Case Study 1 Questions1.     What is the allocated budget  .docxCase Study 1 Questions1.     What is the allocated budget  .docx
Case Study 1 Questions1.     What is the allocated budget .docx
 
Behavior in OrganizationsIntercultural Communications Exercise .docx
Behavior in OrganizationsIntercultural Communications Exercise .docxBehavior in OrganizationsIntercultural Communications Exercise .docx
Behavior in OrganizationsIntercultural Communications Exercise .docx
 
Discussion Question Comparison of Theories on Anxiety Disord.docx
Discussion Question Comparison of Theories on Anxiety Disord.docxDiscussion Question Comparison of Theories on Anxiety Disord.docx
Discussion Question Comparison of Theories on Anxiety Disord.docx
 
I have always liked Dustin Hoffmans style of acting, in this mov.docx
I have always liked Dustin Hoffmans style of acting, in this mov.docxI have always liked Dustin Hoffmans style of acting, in this mov.docx
I have always liked Dustin Hoffmans style of acting, in this mov.docx
 
Is obedience to the law sufficient to ensure ethical behavior Wh.docx
Is obedience to the law sufficient to ensure ethical behavior Wh.docxIs obedience to the law sufficient to ensure ethical behavior Wh.docx
Is obedience to the law sufficient to ensure ethical behavior Wh.docx
 
If you are using the Blackboard Mobile Learn IOS App, please clic.docx
If you are using the Blackboard Mobile Learn IOS App, please clic.docxIf you are using the Blackboard Mobile Learn IOS App, please clic.docx
If you are using the Blackboard Mobile Learn IOS App, please clic.docx
 
Is the proliferation of social media and communication devices a .docx
Is the proliferation of social media and communication devices a .docxIs the proliferation of social media and communication devices a .docx
Is the proliferation of social media and communication devices a .docx
 
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docxMATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
MATH 107 FINAL EXAMINATIONMULTIPLE CHOICE1. Deter.docx
 
If the CIO is to be valued as a strategic actor, how can he bring.docx
If the CIO is to be valued as a strategic actor, how can he bring.docxIf the CIO is to be valued as a strategic actor, how can he bring.docx
If the CIO is to be valued as a strategic actor, how can he bring.docx
 
I am showing below the proof of breakeven, which is fixed costs .docx
I am showing below the proof of breakeven, which is fixed costs .docxI am showing below the proof of breakeven, which is fixed costs .docx
I am showing below the proof of breakeven, which is fixed costs .docx
 
Examine the way in which death and dying are viewed at different .docx
Examine the way in which death and dying are viewed at different .docxExamine the way in which death and dying are viewed at different .docx
Examine the way in which death and dying are viewed at different .docx
 
Karimi 1 Big Picture Blog Post ​ First Draft College .docx
Karimi 1 Big Picture Blog Post ​ First Draft College .docxKarimi 1 Big Picture Blog Post ​ First Draft College .docx
Karimi 1 Big Picture Blog Post ​ First Draft College .docx
 
Please try not to use hard words Thank youWeek 3Individual.docx
Please try not to use hard words Thank youWeek 3Individual.docxPlease try not to use hard words Thank youWeek 3Individual.docx
Please try not to use hard words Thank youWeek 3Individual.docx
 

Recently uploaded

Call Girls in Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
Call Girls in  Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7Call Girls in  Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
Call Girls in Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
9953056974 Low Rate Call Girls In Saket, Delhi NCR
 

Recently uploaded (20)

How to setup Pycharm environment for Odoo 17.pptx
How to setup Pycharm environment for Odoo 17.pptxHow to setup Pycharm environment for Odoo 17.pptx
How to setup Pycharm environment for Odoo 17.pptx
 
Basic Intentional Injuries Health Education
Basic Intentional Injuries Health EducationBasic Intentional Injuries Health Education
Basic Intentional Injuries Health Education
 
AIM of Education-Teachers Training-2024.ppt
AIM of Education-Teachers Training-2024.pptAIM of Education-Teachers Training-2024.ppt
AIM of Education-Teachers Training-2024.ppt
 
Simple, Complex, and Compound Sentences Exercises.pdf
Simple, Complex, and Compound Sentences Exercises.pdfSimple, Complex, and Compound Sentences Exercises.pdf
Simple, Complex, and Compound Sentences Exercises.pdf
 
Food safety_Challenges food safety laboratories_.pdf
Food safety_Challenges food safety laboratories_.pdfFood safety_Challenges food safety laboratories_.pdf
Food safety_Challenges food safety laboratories_.pdf
 
Call Girls in Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
Call Girls in  Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7Call Girls in  Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
Call Girls in Uttam Nagar (delhi) call me [🔝9953056974🔝] escort service 24X7
 
latest AZ-104 Exam Questions and Answers
latest AZ-104 Exam Questions and Answerslatest AZ-104 Exam Questions and Answers
latest AZ-104 Exam Questions and Answers
 
On_Translating_a_Tamil_Poem_by_A_K_Ramanujan.pptx
On_Translating_a_Tamil_Poem_by_A_K_Ramanujan.pptxOn_Translating_a_Tamil_Poem_by_A_K_Ramanujan.pptx
On_Translating_a_Tamil_Poem_by_A_K_Ramanujan.pptx
 
FICTIONAL SALESMAN/SALESMAN SNSW 2024.pdf
FICTIONAL SALESMAN/SALESMAN SNSW 2024.pdfFICTIONAL SALESMAN/SALESMAN SNSW 2024.pdf
FICTIONAL SALESMAN/SALESMAN SNSW 2024.pdf
 
Exploring_the_Narrative_Style_of_Amitav_Ghoshs_Gun_Island.pptx
Exploring_the_Narrative_Style_of_Amitav_Ghoshs_Gun_Island.pptxExploring_the_Narrative_Style_of_Amitav_Ghoshs_Gun_Island.pptx
Exploring_the_Narrative_Style_of_Amitav_Ghoshs_Gun_Island.pptx
 
How to Create and Manage Wizard in Odoo 17
How to Create and Manage Wizard in Odoo 17How to Create and Manage Wizard in Odoo 17
How to Create and Manage Wizard in Odoo 17
 
Understanding Accommodations and Modifications
Understanding  Accommodations and ModificationsUnderstanding  Accommodations and Modifications
Understanding Accommodations and Modifications
 
Sensory_Experience_and_Emotional_Resonance_in_Gabriel_Okaras_The_Piano_and_Th...
Sensory_Experience_and_Emotional_Resonance_in_Gabriel_Okaras_The_Piano_and_Th...Sensory_Experience_and_Emotional_Resonance_in_Gabriel_Okaras_The_Piano_and_Th...
Sensory_Experience_and_Emotional_Resonance_in_Gabriel_Okaras_The_Piano_and_Th...
 
How to Add New Custom Addons Path in Odoo 17
How to Add New Custom Addons Path in Odoo 17How to Add New Custom Addons Path in Odoo 17
How to Add New Custom Addons Path in Odoo 17
 
Towards a code of practice for AI in AT.pptx
Towards a code of practice for AI in AT.pptxTowards a code of practice for AI in AT.pptx
Towards a code of practice for AI in AT.pptx
 
Details on CBSE Compartment Exam.pptx1111
Details on CBSE Compartment Exam.pptx1111Details on CBSE Compartment Exam.pptx1111
Details on CBSE Compartment Exam.pptx1111
 
Basic Civil Engineering first year Notes- Chapter 4 Building.pptx
Basic Civil Engineering first year Notes- Chapter 4 Building.pptxBasic Civil Engineering first year Notes- Chapter 4 Building.pptx
Basic Civil Engineering first year Notes- Chapter 4 Building.pptx
 
FSB Advising Checklist - Orientation 2024
FSB Advising Checklist - Orientation 2024FSB Advising Checklist - Orientation 2024
FSB Advising Checklist - Orientation 2024
 
Graduate Outcomes Presentation Slides - English
Graduate Outcomes Presentation Slides - EnglishGraduate Outcomes Presentation Slides - English
Graduate Outcomes Presentation Slides - English
 
21st_Century_Skills_Framework_Final_Presentation_2.pptx
21st_Century_Skills_Framework_Final_Presentation_2.pptx21st_Century_Skills_Framework_Final_Presentation_2.pptx
21st_Century_Skills_Framework_Final_Presentation_2.pptx
 

of 33© Boardworks Ltd 2008Boardworks AS Biolo

  • 1. * of 33 © Boardworks Ltd 2008 * Boardworks AS Biology Circulation and Blood * of 33 © Boardworks Ltd 2008 * Boardworks AS Biology Circulation and Blood Teacher notes In ‘Slide Show’ mode, click the name of a section to jump straight to that slide. * of 33 © Boardworks Ltd 2008 Why need a transport system? Single-celled organisms, such as bacteria and amoeba (below), can obtain nutrients and excrete waste simply by diffusion. nutrients
  • 2. waste products Multi-cellular organisms, such as insects, fish and mammals, require a more specialized transport system. Why is this? * Boardworks AS Biology Circulation and Blood * of 33 © Boardworks Ltd 2008 Surface area to volume ratio In larger organisms, diffusion of substances would occur far too slowly to enable them to survive: the rate of diffusion increases with the square of the distance it has to travel. Single-celled organisms have a very large surface area to volume ratio, because the diffusion path is so short. This is not just because of its size, however: more important is an organism’s surface area to volume ratio. * Boardworks AS Biology Circulation and Blood Photo credit: Jupiterimages Corporation Teacher notes Flatworms have no specialized transport system but rely on diffusion to distribute oxygen, nutrients and waste products. Students could be asked to state why they think flatworms are able to survive without a transport system.
  • 3. * of 33 © Boardworks Ltd 2008 Surface area and volume * Boardworks AS Biology Circulation and Blood Teacher notes This activity can be used by students to compare the relationship between surface area and volume between different types of shape, e.g. flat rectangles vs. cubes. Students could plot a graph to follow the trends. 29.unknown * of 33 © Boardworks Ltd 2008 Components of circulatory systems Multi-cellular animals overcome the limitations of diffusion by having a specialized circulatory system. This comprises:a heartvessels through which the fluid can flow.a fluid in which substances are transported The two types of circulatory system are open (e.g. molluscs, arthropods) and closed (e.g. vertebrates, a few invertebrates). * Boardworks AS Biology Circulation and Blood Photo credit: Jupiterimages Corporation
  • 4. * of 33 © Boardworks Ltd 2008 Open circulatory systems An open circulatory system consists of a heart that pumps a fluid called haemolymph through short vessels and into a large cavity called the haemocoel. When the heart relaxes, the haemolymph blood is sucked back in via pores called ostia. Haemolymph moves around the haemocoel due to the movement of the organism. heart haemocoel In the haemocoel, the haemolymph directly bathes organs and tissues, enabling the diffusion of substances. * Boardworks AS Biology Circulation and Blood Teacher notes Cephalopod molluscs (octopus, squid and nautilus) have a closed circulatory system. * of 33 © Boardworks Ltd 2008 Closed circulatory systems In a closed circulatory system, blood is fully enclosed within blood vessels at all times. From the heart, blood is pumped through a series of progressively smaller vessels. In the smallest vessels, capillaries, substances diffuse in and out of the blood and into cells. Blood then returns to the heart via a series of progressively
  • 5. larger vessels. heart capillaries * Boardworks AS Biology Circulation and Blood * of 33 © Boardworks Ltd 2008 Closed circulatory systems * Boardworks AS Biology Circulation and Blood Teacher notes Students could be asked to list possible advantages a double circulatory system has over single circulatory systems. A major advantage is that the second pass through the heart gives the blood a boost, increasing it’s rate of flow and enabling oxygen and nutrients to be delivered more quickly to cells. This enables birds/mammals to have a higher metabolic rate than fish. In a double circulatory system, the pulmonary circulation transports blood between the heart and the lungs, whereas the systemic circulation transports blood between the heart and the rest of the body. Amphibians have a double circulatory system but with a three- chambered heart. Students could be asked to sketch what the structure of an amphibian heart might look like.
  • 6. See ‘The Heart’ presentation for more information about the structure of the heart. 38.unknown * of 33 © Boardworks Ltd 2008 The mammalian circulatory system * Boardworks AS Biology Circulation and Blood 41.unknown * of 33 © Boardworks Ltd 2008 Circulation: true or false? 44.unknown * of 33 © Boardworks Ltd 2008 * Boardworks AS Biology
  • 7. Circulation and Blood Teacher notes In ‘Slide Show’ mode, click the name of a section to jump straight to that slide. * of 33 © Boardworks Ltd 2008 Guide to blood vessels * Boardworks AS Biology Circulation and Blood Teacher notes As blood at high pressure enters the artery it expands to lower the pressure. As blood at low pressure enters the artery it recoils to maintain the pressure. The further away from the heart, the less elastic tissue and more smooth muscle an the artery is the less elastic tissue it has and the more smooth muscle. This is because the blood further away from the heart is at a lower pressure. 47.unknown * of 33 © Boardworks Ltd 2008 Identifying blood vessels * Boardworks AS Biology
  • 8. Circulation and Blood Photo credit: Karen Hart, Peninsula College http://www.pc.ctc.edu/hart/index.html 50.unknown * of 33 © Boardworks Ltd 2008 Blood flow in veins * Boardworks AS Biology Circulation and Blood 53.unknown * of 33 © Boardworks Ltd 2008 Varicose veins If a vein wall becomes weakened, valves may no longer close properly. This allows backflow of blood, causing the vein to become enlarged and bumpy, and become varicose. This usually happens in superficial veins, near the skin surface in the lower legs, as opposed to deep veins, which lie underneath muscles. Varicose veins can be surgically removed without affecting blood flow, as most blood is returned to the heart by deep veins. *
  • 9. Boardworks AS Biology Circulation and Blood * of 33 © Boardworks Ltd 2008 Maintaining high blood pressure Blood pressure is the main force that drives blood from the heart around the body.During systole (heart contraction), blood is pumped through the aorta and other arteries at high pressure. The elastic fibres of arteries enable them to expand and allow blood through.During diastole (heart relaxation), the blood pressure in the arteries drops. The elastic recoil of the artery walls help force the blood on. As blood moves through smaller arterioles into capillaries, and then into venules and veins, its velocity and pressure drop continuously. * Boardworks AS Biology Circulation and Blood Teacher notes Students could be asked to draw a line graph of how they think blood pressure varies as it moves through the aorta, arteries, arterioles, capillaries, venules and veins. See the ‘The Heart’ presentation for more information about systole and diastole. * of 33 © Boardworks Ltd 2008
  • 10. Arteries, capillaries and veins 60.unknown * of 33 © Boardworks Ltd 2008 * Boardworks AS Biology Circulation and Blood Teacher notes In ‘Slide Show’ mode, click the name of a section to jump straight to that slide. * of 33 © Boardworks Ltd 2008 What is blood? Blood is a specialized transport medium that is also considered a special type of connective tissue. An average adult has 4–6 litres of blood. Blood has a range of functions such as:transportdefence thermoregulationmaintaining pH of body fluids. * Boardworks AS Biology Circulation and Blood Photo credit: National Cancer Institute / Science Photo Library Coloured scanning electron micrograph (SEM) of human blood showing red and white cells and platelets. Red blood cells (erythrocytes) have a characteristic biconcave- disc shape and
  • 11. are numerous. These large cells contain haemogl obin, a red pigment by which oxygen is transported around the body. They are more numerous than white blood cells (yellow). White blood cells (leucocytes) are rounded cells with microvilli projections from the cell surface. Leucocytes play an important rol e in the immune response of the body. Platelets are smaller cells (pink) that play a major role in blood clotting. Teacher notes Blood, along with bone and cartilage, is considered a type of connective tissue, even though it is quite different to other connective tissues, such as collagen. Embryologically, it has the same origin as other connective tissues, and could be said to connect other body tissues together through the transport of substances. * of 33 © Boardworks Ltd 2008 The composition of blood * Boardworks AS Biology Circulation and Blood Teacher notes The amount of blood occupied by erythrocytes is called the haematocrit. An athlete’s haematocrit is used in drug testing - an elevated level may indicate the athlete has artificially boosted the number of erythrocytes by using the drug erythropoietin, or by ‘blood doping’ - transfusing erythrocytes, either their own (which have been previously harvested and stored) or from a compatible donor. Only about 2% of all the oxygen in blood is transported in the
  • 12. plasma. The vast majority is bound to haemoglobin in erythrocytes. In contrast, most carbon dioxide is transported in the plasma. See the ‘Gas Exchange’ presentation for more information about haemoglobin and the transport of oxygen. See the ‘Immunology’ presentation for more information about leukocytes. 65.unknown * of 33 © Boardworks Ltd 2008 Features of erythrocytes What are the specialized features of an erythrocyte? flattened, biconcave disc shape: ensures large surface area to volume ratio for efficient gas exchange diameter (6–8 µm) larger than capillary diameter: slows blood flow to enable diffusion of oxygen no nucleus or organelles: maximises space for haemoglobin, so more oxygen can be transported large amount of haemoglobin: for transporting oxygen * Boardworks AS Biology Circulation and Blood Teacher notes Only the erythrocytes of mammals and a few other vertebrates have no nucleus. They are present in the erythrocytes of most other vertebrates. The lack of nucleus means erythrocytes cannot divide so most be continuously replaced by new cells produced in the bone marrow. Human erythrocytes live for
  • 13. about 120 days. Haemoglobin makes up about 97% of the dry mass of an erythrocyte. See the ‘Gas Exchange’ presentation for more information about haemoglobin. * of 33 © Boardworks Ltd 2008 Blood clotting * Boardworks AS Biology Circulation and Blood Teacher notes Serum is plasma from which fibrinogen has been removed, therefore preventing it from clotting. Serum is used to treat plasma loss in people with severe burns (loss of outer layer of skin means tissue fluid, but not blood cells, are rapidly lost). 70.unknown * of 33 © Boardworks Ltd 2008 Substances in blood clotting * Boardworks AS Biology Circulation and Blood
  • 14. 73.unknown * of 33 © Boardworks Ltd 2008 Plasma proteins and blood pressure About 8% of blood plasma consists of plasma proteins, of which about half may be albumins. The balance between the hydrostatic pressure of blood (‘blood pressure’) and the osmotic pressure of blood is important in the formation of tissue fluid. These are a group of small proteins involved in the transport of other substances (e.g. fatty acids, hormones) and which help regulate the osmotic pressure of blood. * Boardworks AS Biology Circulation and Blood Photo credit: Borislav Mitev Human serum albumin, to which six molecules of palmitic acid (grey) are bound. Teacher notes See the ‘Transport Across Membranes’ presentation for more information about osmosis. * of 33 © Boardworks Ltd 2008 Formation of tissue fluid
  • 15. * Boardworks AS Biology Circulation and Blood Teacher notes One sign of high blood pressure is oedema – swelling caused by the accumulation of tissue fluid. Students could be asked to explain how this occurs in terms of blood pressure and osmotic pressure. 78.unknown * of 33 © Boardworks Ltd 2008 Lymph Not all tissue fluid returns to the capillaries. The excess drains into the lymphatic system, where it forms lymph. Lymph is a colourless/pale yellow fluid similar to tissue fluid but containing more lipids. The lymphatic system drains into the circulatory system near the vena cavae via the thoracic duct. lymphatic capillaries * Boardworks AS Biology Circulation and Blood Teacher notes Lymph contains fatty substances because digested lipids are transported from the digestive system via the lymphatic system before being returned to the circulatory system. * of 33
  • 16. © Boardworks Ltd 2008 The lymphatic system The lymphatic system is a secondary circulatory system and a major part of the immune system. It consists of:lymphatic capillaries and vein-like lymph vessels, containing valveslymph nodes – sac-like organs that trap pathogens and foreign substances, and which contain large numbers of white blood cellslymphatic tissue in the spleen, thymus and tonsils – these also contain large amounts of white blood cells and are involved in their development. * Boardworks AS Biology Circulation and Blood Teacher notes Lymph moves through the lymphatic system via the action of skeletal muscles and the use of valves to prevent backflow. Lymphatic tissues and lymph nodes are the site of development and maturation of lymphocytes. Lymphatic filariasis is a parasitic disease caused when thread- like nematode worms (transmitted by mosquitoes) become lodged in the lymphatic system. In extreme cases, this causes elephantiasis – a swelling and thickening of skin and underlying tissue, usually in the legs or genitals. * of 33 © Boardworks Ltd 2008 Composition of body fluids
  • 17. * Boardworks AS Biology Circulation and Blood 85.unknown * of 33 © Boardworks Ltd 2008 * Boardworks AS Biology Circulation and Blood Teacher notes In ‘Slide Show’ mode, click the name of a section to jump straight to that slide. * of 33 © Boardworks Ltd 2008 Glossary * Boardworks AS Biology Circulation and Blood 88.unknown * of 33
  • 18. © Boardworks Ltd 2008 What’s the keyword? * Boardworks AS Biology Circulation and Blood 91.unknown * of 33 © Boardworks Ltd 2008 Multiple-choice quiz * Boardworks AS Biology Circulation and Blood 94.unknown The Lamentations of Khakheperre-sonbe1 Introduction (Simpson, 211) “The author of our lamentations … describes the plight of a disorganized land in a time of troubles … [and] a discourse with the man’s other self. … The text is written on
  • 19. both sides of a writing board of Dynasty 18 [c. 1543– 1292 BC] in the British Museum (EA 5645). It was probably composed in the Middle Kingdom [c. 2061–1690 BC] or the Second Intermediate Period [c. 1674-1549 BC]. The last line in the text is complete but lacks any indication that it represents the end of the composition. Perhaps the composition was continued on another tablet.” Introduction (Erman, 108)2 “As is evident from his name, Khakhepperre-sonbu (“Khekheperre is in health”), the author lived under King Sesostris II, i.e. about 1900 B.C. As the text is written on the writing-board of a school-boy of the Eighteenth Dynasty, it was evidently regarded at that time also as a classical work. … the author expresses a desire to discover new and unheard-of utterances, with which to ador n his complaint. The book is in the form of the colloquy3 of a man with his own heart as his only true friend. … We know nothing, apart from this work, about the calamity which the writer deplores, though, to be sure, in view of our inadequate knowledge of Egyptian history, we cannot exactly be surprised at this.” Introduction (Lichtheim, 145)4 “… The single preserved copy was dated by Gardiner to the
  • 20. middle of the Eighteenth Dynasty, while the work itself clearly belongs to the Middle Kingdom. In fact, it can be dated with some assurance to the reign of Sesostris II or shortly after …. If a political criticism was intended, it is concealed behind the generalized metaphors on the theme of anarchy and distress. … the laments on the "distress of the land" are metaphors. They are either purely literary, designed to enlarge the literary possibilities of the theme, or they may have conveyed a covert political criticism, of a kind that could not be made openly and hence was wrapped in metaphor. … the author addresses his plaints to his heart, a device that further enhances the rhetorical character of the work. The text consists of fourteen lines on the recto and six lines on the verso; and the lines are grouped into four sections by means of short dividers. As written on the board, the text is complete, for after the fourth section there are two lines in a larger handwriting which are not connected with it. The text, however, may be the first part of a lost longer work." RECTO5 The gathering6 together of sayings, the culling of phrases, the search for words by an
  • 21. inquisitive mind7, which the wab-priest8 of Heliopolis9, Seny’s son Khakheperre-sonbe who is called Ankhu, wrote. He said: Would that I had unknown speeches, erudite phrases in new language10 which has not yet been used, free from (the usual) repetitions, not the phrases of past speech which (our) forefathers spoke. I shall drain myself11 for something in it in giving free rein to all I shall 1 Simpson, William Kelly (ed.). The Literature of Ancient Egypt (3rd ed.). New Haven, CT: Yale University Press, 2003. 2 Erman, Adolf (ed.), The Ancient Egyptians. New York: Harper & Row, Publishers: 1966 [a revised translation of the 1923 original book in German; includes an introduction by William K. Simpson]. 3 “a conversational exchange; dialogue” (dictionary.com). 4 Lichtheim, Ancient Egyptian Literature, vol 1: The Old and Middle Kingdoms. University of California Press, 1973. 5 “a right-hand page of an open book or manuscript; the front of a leaf” (dictionary.com). 6 “He thinks of himself as plucking flowers” (Erman, 108, fn 4). “the heaping of sayings” (Lichtheim, 146). 7 “heart” (Erman and Lichtheim) 8 “… the duty of this priest was to pour out the drink-offering … [and] to examine into the purity of the sacrificial animals” (Erman, A. Life in Ancient Egypt. H.M. Tirard (trans.), New York: Dover Publications, Inc., 1971. Reprint of 1894 original).
  • 22. 9 The town of “On” (as in the Bible). 10 “Novel, untried words” (Lichtheim, 146). 11 “I wring out my body” (Erman, 109). “The body is accounted the seat of the thoughts” (Erman, 109, fn 1). “I wring out my body of what it holds/ In releasing all my words” (Lichtheim, 146). say. For indeed whatever has been said has been repeated, while what has (once) been said has been said. There should be no boasting about the literature of the men of former times or what their descendants discovered12! The speaker has not (yet) spoken. One who will speak now speaks13. What another has found will be said. Not a tale of telling after the fact: they did it before. Not yet a story for future telling. Such is seeking disaster. It is falsehood. And there is no one who shall recall such a man’s name to the people. I have said these things just as I have seen, beginning with the first generation down to those who shall come afterward, when they (too) shall imitate the past.14 Would that I might know what others did not know15, even what has not yet been
  • 23. repeated, that I might know what others did not know, even what has not yet been repeated, that I might speak and my heart answer me, that I might enlighten my grief to it, and that I might thrust onto it the weight which is on my back16, (and speak) thoughts about what afflicts me, that I might express to it what I suffer through it, that I might speak, Yea, about my feelings17! I am thinking about what has happened18, the things that have come to pass throughout the land. Changes are taking place. It is not like last year; one year is more troublesome19 than the next. The land is in chaos, has become my destruction, has been made into a state of unrest20. Justice has been cast out, and evil is inside the shrine21. The designs of the gods are disturbed, and their perquisites22 are passed over. The land is in dire state. Mourning is everywhere. Towns and districts are in lamentation. All alike are grief stricken. The back is turned on anything of worth23; the tranquil are distressed. Troubles occur daily, and the face shrinks from what is about to happen.
  • 24. I will say my say about it; for my limbs are heavy laden24. I am distressed in my heart, and it is painful25 to hide my thoughts about it. Although another heart would break, a stout heart in a difficult situation is the companion of its master. 12 “found” (Lichteim, 146); "Gmi [Ancient Egyptian word], 'find,' here and below in line 5, in the pregnant sense of 'find useful,' 'make use of'" (Lichteim, 148, fn 1). 13 “Not speaks one who spoke/Then speaks one who will speak” (Lichtheim, 146). 14 “No one is original; the ‘first generation’ is of course merely a manner of speech” (Erman, 109, fn 3). "It is interesting that imitation of the past, which is usually recommended in the [Ancient Eygptian genre of] Instructions, is here rejected" (Lichtheim, 148, fn 2). 15 “Would that I know what others ignore” (Lichtheim, 147). 16 “Shift to it the load on my back” (Lichtheim, 147). 17 “And sigh ‘Ah’ with relief” (Lichtheim, 147). 18 “Here begins the prallell text of the ostracon” (Simpson, 212) [ostracon: “a potsherd” (dictionary.com). These broken pieces of pottery were used for writing practice in Egyptian schools.] 19 “Irksome” (Lichtheim, 147). 20 “The land breaks up, is destroyed/Becomes [a wasteland]” (Lichtheim, 147). 21 “Order is cast out/Chaos is in the council hall” (Lichtheim, 147); "… the pair is maat [“order,” here “justice”] and
  • 25. isfet [“chaos,” here “evil”]" (Lichteim, 148, fn 3). These are central terms in the Ancient Egyptian understanding of the universe. 22 “something demanded or due as a particular privilege” (dictionary.com). Erman translates this sentence as, “The plans of the gods are destroyed and their ordinances transgressed” (109). 23 “The back is turned upon respect” (Erman, 109); “one turns one’s back on dignity” (Lichtheim, 147). 24 “He would fain complain of his misery, for it is painful to hide it in the body” (Erman, 109). “The lords of silence are disturbed” (Lichtheim, 147). 25 "whd [Ancient Egyptian word] occurs four times, varying from 'painful' to 'suffer,' and 'endure' (I, 13-4, and II, 4- 5)" (Lichtheim, 149, fn 5). O would that I had a heart that knew how to suffer. Then I might alight, and I would load it with phrases of misery, and I might drive off to it my suffering26. VERSO27 He said to his heart: Come now, my heart, that I may converse with you and you may answer me my sayings, that you may interpret for me that which is throughout the land28, for
  • 26. those who were radiant (in white garments) have been cast down.29 I am thinking30 about what has taken place. Misery is ushered in today. By the morning the strangers have (still) not passed away31. Everyone is silent about it. The entire land is in a serious plight32, and there is nobody free from wrong: all people alike do it. Hearts are dejected33. The one who gives commands is (now) one to whom commands are given, and the hearts of both are quieted34. One rises to these things daily, and hearts have not thrust them aside35. Yesterday’s state is like today’s, because of the passing by of many things. The countenance is perplexed. There is no man wise enough to know it, and there is no man angry enough to speak out. Every day one wakes to suffering. Long and burdensome is my suffering. There is not strength for the wretched to rescue him from one stronger than him36. Silence about what is heard is painful. It is miserable to have to give an answer to the ignorant37. To oppose a speech makes
  • 27. for disaffection. The heart cannot accept truth. A reply to a speech is insufferable38. All a man wants is his own talk. Everyone is based in crookedness. Precision in speech39 is abandoned. I speak to you, my heart, that you may answer me. Yet a heart which is appealed to cannot be silent. The needs of a servant40 are like those of a master41. Plentiful (now) are the things which weigh upon you42. 26 “Then I would rest upon it that I might load it with words of misery, that I might drive to it my pain” (Erman, 110). 27 “a left-hand page of an open book or manuscript” (dictionary.com) 28 “expound to me the things that are throughout the land, that are bright and lie outstretched” (Erman, 110) 29 “What is in view of all, yet is comprehended of none” (Erman, 110, fn 1).”those who shone are overthrown” (Lichtheim, 148); "the great man is overthrown" (Lichtheim, 149, fn 6). 30 “I meditate” (Lichtheim, 148). 31 “And turmoil will not cease tomorrow” (Lichtheim, 148). 32 “The whole land is in a great condition” (Erman, 110); “’Condition’ for ‘bad condition’” (Erman, 110, fn 2). 33 "… probably 'greedy' rather than 'sad' [here, ‘dejected’]" (Lichtheim, 149, fn 8). 34 “both submit” (Lichtheim, 148).
  • 28. 35 “Everyday men rise up early thereto” (Erman, 110). “One wakes to it everyday,/And the hearts do not reject it” (Lichtheim, 148). 36 “The sufferer lacks strength to save himself/From that which overwhelms him” (Lichtheim, 147). 37 “The meaning of the passage probably is: It is not right, my heart, that you answer me nothing, and wherefore whould I speak to you, if you wish to know nothing about it?” (Erman, 110, fn 3). "… the sense is 'lacking, deficient'; hence 'futile' seems appropriate here" (Lichtheim, 149, fn 10). 38 “one cannot bear a statement of fact” (Lichtheim, 148). 39 “Right-speaking” (Lichtheim, 148). 40 “The servant is the heart, which also suffers, if the man, its master, suffers” (Erman, 110, fn 4). 41 “Lo, servant and master fare alike” (Lichtheim, 148). 42 “The tablet ends here and perhaps the text as well” (Simpson, 213).