Key Points Nutrition Respiration Transportation Excretion

1. CHAPTER - 6
LIFE PROCESSES
Subhasish Khanda
Subha.subhasish.khanda@gmail.com

2. Criteria to decide whether something is alive
●Responses to the stimuli
●Growth & Development
●Reproduction
●Movement

3. Life Processes
The basic processes in living organisms necessary for maintaining life.
Nutrition Respiration
Transportation Excretion
The basic life processes-

4. Nutrition
Process of taking food by an organism and its utilization by
the body.
 To build the body
 For growth
 To repair the damaged parts of the body
 For energy
Purpose:

5. Modes of Nutrition
Autotrophic
Nutrition
Heterotrophic
Nutrition
Nutrition (Modes)
(Green Plants, BGA) (All animals, Fungi )
Holozoic
Nutrition
Saprophytic
Nutrition
Parasitic
Nutrition
(Mushroom, Bread mould) (Plasmodium, Round worm) (Amoeba, Paramaecium,
Birds, Humans)

6. Nutrition in Plants
The process by which plants uses carbon dioxide and water in the
presence of sunlight and chlorophyll to prepare their food carbohydrate
(stored in the form of starch) and converted light energy to chemical
energy. Produces water and Oxygen as byproduct..
Sunlight
6CO2 +12H2O
Chlorophyll
C6H12O6 + 6H2O + 6O2
Equation
Photosynthesis Photo synthesis
+
Raw Materials
 Carbon dioxide
 Water
 Chlorophyll
 Sunlight
Product
 Carbohydrate (Starch)
 Water
 Oxygen

8. o Green pigments present in the leaves.
o Chlorophyll-a, Chlorophyll-b, Chlorophyll-c, Chlorophyll-d
o Cells containing green dot like structures called chloroplasts
which contain chlorophyll.
Chlorophyll

10. Process of photosynthesis
i) Absorption of light energy by chlorophyll & conversion of light energy
into chemical energy
ii)Splitting up of water molecules into hydrogen and oxygen.
iii) Reduction of carbon dioxide by hydrogen to form carbohydrates.
Process of Photosynthesis
Light Dependent Reaction
 Use light energy
 Takes place in the thylakoid membrane is the Grana
Dark Independent Reaction
 Takes place in the thylakoid membrane is the Stroma

11.  Tiny pores present in the leaves
 Exchange gases
 Each stoma has a pair of guard cells
Stomata

14. Nutrition in Animals
Nutrition in Amoeba
Mode: Holozoic Nutrition

15. Nutrition in Human
Mode: Heterotrophic Nutrition
System: Digestive system
Components of Digestive system: Alimentary canal & Glands (producesenzymes)
Organs of Digestive system
 Mouth
 Oesophagus
 Stomach
 Small Intestine
 Large Intestine
 Anus
Glands of Digestive system
 Salivary glands
 Gastric glands
 Liver
 Pancreas
 Intestinal glands

17. Organs Gland Enzyme Function
Mouth Salivary Glands
(Saliva)
Salivary Amylase Converts starch
into sugar
Stomach Gastric Glands
(Gastric juice)
 Peptic Cell
 Oxyntic Cell
 Mucous Sec. Cell
Pepsin Breaks down
proteins
Hydrochloric acid
(Not an enzyme)
Makes the medium
acidic
Mucous
(Not an enzyme)
Protection of the
walls of stomach
Alimentary Canal & Glands

18. Organs Gland Enzyme Function
Small
Intestine
Liver
(Bile juice)
No enzyme
(Bile salts)
Breaks fats
Pancreas
(Pancreatic juice)
Trypsin Breaks proteins
Lipase Breaks fats
Walls of the small
intestine
(Intestinal juice)
• Carbohydrates into
Glucose
• Fats into fatty acids
and glycerol
• Proteins into amino
acids
Large
Intestine
No significant digestive activity
Absorption of water & Removal of waste material through anus
Cont.

19. Respiration
Respiration is the process by which food is burnt in
the cells of the body with the help of oxygen to
release energy.
Place of occurrence:
• Mitochondria
• Cytoplasm

20. Types of Respiration
Aerobic Anaerobic
• Presence of oxygen
• Products: Carbon dioxide
Water
and energy
• Energy release: More (38 ATP)
Glucose Pyruvate CO2 + H2O +Energy
presence of oxygen presence of oxygen
in cytoplasm in mitochondria
• Absence of oxygen
• Products: Carbon dioxide
lactic acid/ ethanol
and energy
• Energy release: Less (04 ATP)
Aerobic
presence of oxygen absence of oxygen
Glucose Pyruvate Lactic acid + Energy
in cytoplasm in muscle cells
Anaerobic in muscle cells
Anaerobic in Yeast
Glucose Pyruvate Ethanol + CO2 + Energy
presence of oxygen absence of oxygen
in cytoplasm in Yeast

21. Breakdown of glucose by various pathways
presence
of oxygen
CO2 + H2O + Energy
(in mitochondria)
presence
of oxygen
absence
of oxygen
Glucose Pyruvate
+
Energy
Lactic acid + Energy
in cytoplasm (in muscle
cells)
absence
of oxygen
Ethanol + CO2 + Energy
(in yeast)

23. Respiration in Humans
Main organs
 Nostrils
 Nasal cavity
 Pharynx
 Larynx
 Trachea
 Bronchi
 Bronchioles
 Lungs
 Diaphragm

25. Mechanisms of Breathing
●When air in, the muscles
of the diaphragm contracts
and moves downward and
the chest cavity expands
and air enters into the
lungs.
●When air out, the
muscles of the diaphragm
relaxes and moves
upward and the chest
cavity contracts and air
goes out of the lungs.

26. • Blood: Transport dissolved gases, nutrients and waste products
• Blood vessels: Blood flows around the body(Arteries,Veins,Capillaries)
• Heart: Pumps blood around the body
• Valves: Ensure blood flow in one direction only
Transportation
Transportation in Human
The main transport system in human beings is the circulatory system
Components of Circulatory system
• Open
• Closed (Blood remains enclosed and circulates in a system of tubes)
Types of circulatory systems:

28. • Closed circulatory system, called the cardiovascular system
• Cardio = Heart; Vascular = Blood vessels
• Circulatory system is a double system.
• Blood flows through two distinct circulations –
o The Pulmonary
o The Systemic
Human Circulatory System
The right side pumps blood to the lungs, which returns to the left
side of the heart.
The left side pumps blood to the rest of the body, which returns to
the right side of the heart.

29. • Surrounded by pericardium
• Situated in the middle of the
chest thorax.
• Protected by the ribs and
sternum.
‘Pump house’ Pumps blood to all parts of the body

30. Right Atria* Left Atria
Right Ventricle Left Ventricle
 Four chambers (Atrium & Ventricles)
Atrium:
 Collection units
 Walls are thinner
Ventricles:
 Distribution Units
 Walls are thicker
 Right and left chambers
separated by Septum

31. Blood Vessels Functions
Arteries Carry oxygenated blood away from heart
(Exception: PA)
Veins Carry deoxygenated blood towards heart
(Exception: PV)
Capillaries Connect arteries and veins
Pulmonary Arteries Carry deoxygenated blood from heart to lung
Pulmonary Veins Carry oxygenated blood from lung to heart
Vena Cava Carry deoxygenated blood from body to heart
Aorta Carry oxygenated blood from heart to body
Valves Functions
Mitral Valves Separate Left Atrium to Left Ventricle One
directional
blood flow
Tricuspid Valves Separate Right Atrium to Right Ventricle

32. Working of Heart (Blood Circulation)

33. Blood Pressure
Force exerted by blood against the walls of blood vessels
Factors maintain blood pressure
 Systole: Contractions of ventricle
 Diastole: Relaxation of ventricles
• Systolic BP: Maximum pressure in the aorta when ventricles contract
The pressure of blood inside the artery during ventricular systole
(contraction) is called systolic pressure
• Diastolic BP: Lowest pressure in the aorta when ventricles relax
The pressure of blood inside the artery during ventricular diastole
(relaxation) is called diastolic pressure
BPrecorded with systolic over diastolic, e.g. 120/80 mm Hg.
Normal Systolic Pressure is about 120 mm Hg
Diastolic Pressure is about 80 mm Hg.
Instrument measure BP: Sphygmomanometer

34. Transportation in plants
Why? • To receive nutrients
• No circulatory system
• Supply of water
Through
xylem
UNIDIRECTIONAL FLOW OF WATER & MINERALS
ROOT STEM
MULTIDIRECTIOAL FLOW OF FOOD IN PLANTS
LEAVES Through
phloem
Stem

35. Transportation in plants takes place through conducting tissues-
1. Xylem
2. Phloem
• Tracheids
• Tracheae
• Xylem parenchyma
• Xylem fibre
Elements of Xylem:
Elements of Phloem:
• Sieve tubes
• Sieve cells
• Phloem parenchyma
• Phloem fibre

36. Excretion
• Process of removal of waste produced during metabolic activities
• Unicellular organism by diffusion
• Multicellular organisms through specialized organs
Excretion in Human
Components of Excretory System
 Kidney (pairs)
 Ureter (pairs)
 Urinary Bladder
 Urethra

37. Colour: Reddish brown
Structures: Bean shaped
Kidney

39.  Gaseous waste products removed through the stomata.
 Excess water removed through the stomata (Transpiration)
 Some waste products are stored in -
 Leaves
 Barks
 Roots
 Fruits
 Vacuoles
 Old xylem cells (gums and resins)
Excretion in Plants

40. The kidneys in human beings are a part of the system for
(a) Nutrition (b) Respiration (c) Excretion (d) Transportation
The xylem in plants are responsible for
(a) Transport of water (b) Transport of food
(c) Transport of amino acids (d) Transport of oxygen
The autotrophic mode of nutrition requires
(a) Carbon dioxide and water (b) Chlorophyll
(c) Sunlight (d) All of the above
EXERCISES
The breakdown of pyruvate to give carbon dioxide, water and
energy takes place in
(a) Cytoplasm (b) Mitochondria (c) Chloroplast (d) Nucleus
Which protein digesting enzyme is present in pancreatic juice ?
Trypsin
(c) Excretion
(a) Transport of water
(d) All of the above
(b) Mitochondria

41. How are fats digested in our bodies? Where does this
process take place?
What is saliva? What roles saliva play in digestion?
Digestion of fat takes place in the small intestine. Fat reaches the small
intestine in the form of large globules. The liver releases bile juice which
breaks down the large globules into smaller globules. Pancreatic juice
contains enzyme called lipase, which also breaks down the globules into
molecules.
The process takes place in the small intestine.
Saliva is a watery fluid secreted by salivary gland.
The digestive functions of saliva are-
 Moistening of foods and helping it to swallowed easily.
 Saliva contains the enzyme amylase that break down starches into
glucose.

42. What are the necessary conditions for autotrophic nutrition and
what are its by products?
What are the differences between aerobic and anaerobic respiration?
Name some organisms that use the anaerobic mode of respiration.
Carbon dioxide, water, chlorophyll pigment, and sunlight
Water & Oxygen are its by product
Organisms use anaerobic mode of respiration are yeast, bacteria

43. How are the alveoli designed to maximize the exchange of gases?
What would be the consequences of a deficiency of haemoglobin in
our bodies?
Alveoli are balloon-like structure that provides maximum surface area
for exchange of gases. Thin-walled alveoli and richly supplied network
of blood vessels facilitate the maximum exchange of gases between
blood and the air.
Deficiency of haemoglobin in the blood can affect oxygen supply. This can
lead to a deficiency of oxygen in the body cells, which leads to a disease
called anaemia.
State two functions of stomata [2020]
• Exchange of gases
• Transpiration

44. Describe double circulation in human beings. Why is it necessary?
What are the differences between the transport of materials in
xylem and phloem?
During a single cycle blood goes twice in the heart (Systematic
circulation & Pulmonary circulation) which is known as double
circulation.
It is necessary in human being to separate oxygenated and de-
oxygenated blood.
• Xylem tissue helps in the transport of water and
minerals. Phloem tissue helps in the transport of food.
• Transport in the xylem requires physical forces such as transpiration
pull. Transport of food in phloem requires energy in the form of ATP

45. Why is there a difference in the rate of breathing between aquatic
organisms and terrestrial organisms? Explain. [2020]
The amount of oxygen dissolved in water is lower as compared to the
amount of oxygen in air. Aquatic organisms therefore have to breath faster
than terrestrial organisms to absorb the required amount of oxygen from
the water.
Explain why plants have low energy needs as compare to animals?
[2019]
Majority of plants do not move and they have a large proportion of dead
cells in many tissues. Thus plants requires low energy as compare to
animals.
Mention any two components of blood. [2018]
• Plasma
• Red Blood Cells (RBC)
• White Blood Cells (WBC)
• Platelets

46. Why do the walls of the trachea not collapse when there is less
air in it?
Rings of cartilages are present
in trachea. These rings
support the trachea and do not
allow the trachea to collapse
when there is less air in it.
Name the organs that forms excretory system in human beings.[2020]
• Kidney (pairs)
• Ureter (pairs)
• Urinary Bladder
• Urethra

47. Compare the functioning of alveoli in the lungs and nephrons in
the kidneys with respect to their structure and functioning.
Alveoli are tiny balloon-like structures present inside the lungs. The
walls of the alveoli are one cell thick and it contains an extensive
network of blood capillaries.
Nephrons are tubular structures present inside the kidneys.
Nephrons are made of glomerulus, bowman's capsule, and a
long renal tube
Trace the movement of oxygenated blood in the body [2018]
Lungs Left atrium aorta body organs
Write the function of valves present in between atria and ventricles.
[2018]
Prevent back flow of blood

48. Write one structural difference between the composition of artery
and veins. [2018]
Define excretion [2018]
Name the basic filtration unit present in the kidney. [2018]
• Artery has thick elastic wall and vein is thin walled
• Valves are present in the veins and not in arteries
The Processes in which harmful metabolic waste (nitrogenous waste)
are removed from the body is called as excretion.
Nephron
Name two excretory products other than O2 and CO2 in plants
Resins and gums
Water and minerals are transported within the plant by Xylem vessels
(mainly in an upward direction) because of the transpiration pull.
How does water enter continuously into the root xylem?.[2019]
OR
How are water and minerals transported in plants ?

49. When do the desert plants take up carbon dioxide and perform
photosynthesis ?
Desert plants open up their stomata during night and take CO2. During the
day time stomata remains close to prevent the loss of water by
transpiration. During night plants collects and store CO2 in their cells.
During the day time they carry out photosynthesis to prepare their food. .
In single celled organisms diffusion is sufficient to meet all their
requirements of food, exchange of gases or removal of wastes but
it is not in case of multicellular organisms. Explain the reason.
Unicellular organisms can meet all their requirements through diffusion
because of its complete contact with the atmosphere, but in multicellular
organisms all cells are not in direct contact with the atmosphere. Thus the
rate of diffusion is very less. Organisms requires more oxygen to sustain
life processes which cannot be fulfilled by the process of diffusion.

50. Mention the raw materials required for photosynthesis.
• Carbon Dioxide
Explain how does the exchange of gases occur in plants.
In plants, tiny pores like structure called stomata are present on leaves
and lenticels in stem which facilitates the exchange of gases. Carbon
dioxide is taken in and oxygen given out {during photosynthesis} and
vice versa during respiration.
How do guard cells regulate the opening and closing of stomatal
pore?
The opening and closing of pore is a function of guard cells. The guard
cells swell when water flows into them causing opening of stomatal pore.
Similarly, pore closes when guard cells shrink by loosing of water.
• Water
• Sunlight
• Chlorophyll

51. List three characteristics of lungs which make it an efficient
respiratory surface.
1.Thin walled air sacs: The thin walls of air sac helps in quick diffusion
of gases. Which helps Oxygen and Carbon dioxide to circulate easily
through lungs.
2.Moistness of air sac: moist air sacs can dissolve gases before
diffusion.
3.Large surface area: Alveoli looks like tennis rackets. Thus the
surface area for absorption of gases increased.
4.Good blood supply: Air sacs or alveoli have a large capillary network
so more flow of blood leads more exchange of gases.
What is transpiration in plants?
The process through which plants loss excess water as water vapour.

52. What will happen to a plant if its xylem is removed?
Xylem in plant transports water and dissolved mineral nutrients from
the roots to leaf. So, if xylem is removed from the plant, the water and
mineral supply to the plant will stop and therefore, the plant will die.
What happens to the rate of breathing during vigorous exercise
and why?
During vigorous exercise the rate of breathing will increases by about
20 to 25 times per minute. Because, during vigorous exercise the
demand for oxygen increases.
Villi are finger like projections in the small intestine. They are richly
supplied with blood vessels which helps to increase the surface area for
absorption of the digested food in to the blood stream.
State the role of Villi in human digestive system

53. Leaves of a healthy potted plant were coated with vaseline to
block the stomata. Will this plant remain healthy for long? State
three reasons for your answer.
No, the plant will not remain healthy. it will begin to die, because-
• Gaseous exchange will not take place.
• No absorption of CO2 through stomata, hence no photosynthesis.
• Transpiration will not occur, so no transpiration pull, hence no
transportation of water.
What is translocation in plants?
The movement of soluble materials, products of photosynthesis from
leaves to other tissues throughout the plant
• HCl helps to kill germs, entered in to the system through food.
• It creates medium acidic for pepsin to breakdown proteins.
State the role of HCl in human digestive system

54. Describe in brief how urine is produced in human body. [2020]
Each kidney has large numbers of filtration units
called nephron. Nephron filter blood and produce
urine in multiple steps. The blood passes different
parts of nephron. Some substances such as
glucose, amino acids, salts and a major amount of
water, are selectively re-absorbed as the urine
flows along the tube and some substances like
urea, uric acid and creatinine are filter out as
components of urine.
Next to it, the urine goes to urinary
bladder through ureters. In the bladder, urine
stored for some time before urination. Later on
urine is excreted out through urethra.

55. Write two water conducting tissue present in plants [2019]
Xylem vessels and Xylem tracheids
Why it is necessary to separate oxygenated and deoxygenated
blood in mammals and birds
Mammals and birds are animals which can be called warm-blooded
animals. Warm-blooded animals have the characteristic that they can
produce body heat, even if it is cold outside. It is necessary that the
oxygenated and Deoxygenated blood is separated so that the body does
not generate excessive heat due to excessive production of carbon
dioxide.
What are outside raw materials used for by an organism
Food, Oxygen and Water
What process would you consider essential for maintaining life
Nutrition, Respiration, Excretion, Transportation, Reproduction
What criteria do we use to decide whether something is alive
• Growth
• Reproduction
• Metabolism
• Movements