2. INTERNALENVIONMENT
It is the condition that prevails within the
body of an organism, particularly with respect
to the composition of the tissue fluid.
First proposed by the French physiologist
‘CLAUDE BENARD’ (1813 – 78).
He states that maintenance of a constant
internal environment was necessary for the
survival of an organism in a varying external
environment.
3. ROBERTHOOKE (1665)
Using an early
microscopic
viewed cork
and saw many
repeating box
like structure s
and called
them ‘cell’
4. A CELL
A cell is chemical
system that able to
maintain its
structure and
reproduce cells are
the fundamental
units of life . All
livings are
composed of cells
5. STRUCTURE OF A CELL
• NUCLEUS –
a)It stores the cell hereditary material or DNA.
b)It coordinate the cell activities which include growth
intermediary metabolism, protein synthesis and
reproduction ( cell division).
• CELL MEMBRANE
a) It consist of a lipid bilayer with embedded protein.
b) It protect the cell from its surrounding
c) It controls the movement of substance in and out of
cell and organelles
6. • CYTOPLASM- substance that fills the cell.
a) It is jelly like substance
b) made up of 80% water and is clear and
colorless
c) It also consist of carbohydrates ,
inorganic salts , lipids and enzymes.
• RIBOSOME – It is a protein synthetic
machinery.
a) It has two subunits – large and small.
b) Made of protein and ribosomal RNA .
7. • MITOCHONDRIA –
a) It is organelle within eukaryotic cells
b) produce adenosine triphosphate
(ATP), the main energy molecules used
by the cell.
c) Therefore it is also called ‘the
powerhouse of the cell’.
• ENDOPLASMIC RETICULUM –
a) A web -like series of membrane within the
cytoplasm in the form of flattened sheets ,
sacs , tubes .
b) It creates many membrane enclosed
spaces – spreads throughout the
cytoplasm.
8. • CENTRIOLES –
a) They are part of specialized region of the
cell the called centrosome.
b) They are involved in the production of
micro tubes which have many function
including moving chromosomes during
cell division.
• GOLGI APPARATUS
a) Responsible for transporting , modifying
and packaging protein and lipids into
vessels for delivery to target destination.
10. CELL COLONIES
• First step towards cell specialization.
• Clumping towards of otherwise
independent cells must had survival
value among cell species.
• Interdependence in multicellular
organisms.
11. TISSUE SPECIALIZATION
• It is a group of cells that are specialized
in a similar way to perform a common
function.
• Its main function are contraction,
receptors tissue for irritability , nerve
tissue for conduction, glandular tissue for
secretion etc.
• Other types of specialized : bone, cartilage
, connective tissue and vascular tissue.
12. ORGAN SPECIALIZATION
• A organ is a collection of differently specialized
tissue, organized for the performance of a
common general function.
• Each tissue has a different role in the overall
function of a organ.
• For example- the stomach is a digestive organ. It
is made up of connective tissue to hold it
together , vascular tissue to nourish it, glandular
tissue to provide digestive secretion , muscular
tissue to mix the food and move it into other
parts of digestive system.
13. SYSTEM SPECIALIZATION
• It is a highest level of integration in the
body.
• It consist of several organs , each of which
has a limited role in the overall performance
of the system.
• Example – The nervous system has nerves to
carry excitation to and from the receptors
and effectors, brain centers to make
connection between incoming and outgoing
excitation and so forth.
14. INTEGRATION OF THE COMPLEX
ORGANISM : HOMEOSTASIS
• The physical and chemical condition that
surrounds a specialized cell in the human
body must be more constant because the
cell has lost its ability to cope with
environmental changes.
• it can carried out in three major ways:
i. The organisation of tissue and organs
into system along with coordination for a
single function.
15. ii. Some coordination is supplied by endocrine
glands , whose secretion are carried all over
the body in the blood stream to affect
widely scattered tissue in a constant
fashion.
iii. The nervous system is completely devoted
to coordinating the many diverse functions
of the other organs and system of the body.
• Every change in the external and internal
environment or both tends to alter internal
conditions from those needed by the
specialized cells for adequate functioning
and survival that is ‘functional integrity’ .
16. METABOLISM OF A CELL
CELL METABOLISM
a. The activities of the
individual cell that
are involved in
transforming food
and oxygen into
cellular structure
and eliminating
waste from the cell
are called cell
metabolism
INTERMEDIARY
METABOLISM
i. The chemical reactions
involve simple chemical
‘food’ compounds-
blood glucose , amino
acids , fatty acid,
minerals and oxygen
that have been broken
down from more
complex compounds in
this process
17. CELL AS A CHEMICAL FACTORY
• ANABOLISM –
metabolic reaction
that require
energy input to
proceed are
collectively known
as anabolism.
• CATABOLISM–
The necessary
energy is supplied
other chemical
reaction that
release energy
collectively known
as catabolism.
18. CONTROL OF METABOLISM
•The necessary energy , structure
and food for the cell . The rate at
which chemical reaction can
proceed often depends on
enzymes
19. •CATALYSTS are chemical that
speed up the rate at which chemical
reaction go on without being used up
in the reactions.
20. CONTROL OF METABOLISM BY THE
CIRCULATORY SYSTEM
• Circulating system consist of:
i. The heart which maintains the flow of blood
by its pumping action.
ii. The pulmonary circulation system of blood
vessels which carries oxygen between the
heart and the lungs.
iii. The systematic circulation system which
carries blood from the heart to all the other
tissue of the body and back again to the heart
.
21. It plays a role in maintenance of other
body system by transporting hormones
and nutrients taking away waste
products and providing all living body
cells with a fresh supply of oxygen and
removing carbon dioxide.
Homeostasis is disturbed if the
cardiovascular are or lymphatic systems
are not functioning correctly.
22. Homeostasis and the internal
environment
Oxygen and carbon dioxide content of the
blood are controlled by the co2 level.
The acidity of the blood is also critical .
Blood glucose level is maintained between
60 and 130mg/100ml of blood.
The endocrine glands as well as the nervous
system, organize the body response to
response to change.
The chemical composition of the blood is
also regulated the by such mechanism.
23. The body temperature must be kept
within narrow limits .
Change in blood temperature must
be kept within narrow limits.
Regulatory behavior is a part of the
homeostatic process