Life Process CBSE Test Paper - 02 for class 10
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setter CBSE TEST PAPER-02
SCIENCE
& TECHNOLOGY (Class-10) Chapter
6 : Life Process
1. Point out of differences between an artery and vein. (1
mark)
Ans:
Any one:
Artery
1.
Vessels which carry blood from the heart to various body parts
2.
Arteries carry oxygenated blood from the heart except pulmonary artery
3.
Arteries have thick elastic muscular walls
4.
Valves are absent
5.
Blood flows under high pressure
Vein
1.
Vessels which carry blood from the various body parts to the heart
2.
Veins carry deoxygenated blood from the various body parts except pulmonary
vein
3.
Veins have thin non elastic walls
4.
Valves are present to prevent the backward flow of blood
5.
Blood flows under low pressure
2. Write the two functions of kidneys.
4.
What is the difference between stroma and grana? (2 marks)
Ans:
Grana
|
Stroma
|
The stacks of thylakoids are called
grana.
|
Grana are connected by intergrana or
stroma thylakoids
|
Grana contribute to chloroplasts'
large surface area to volume ratio.
|
It carries all the enzymes, e.g.,
RUBISCO, needed to carry out the "dark" reactions of photosynthesis
|
5. Write two differences between the
transport of materials in xylem and phloem. (2 marks)
Ans:
Xylem
|
Phloem
|
(i) Functional xylem ells are dead.
|
(i) Functional phloem cells are alive.
|
(ii) It carries mineral salts, water
and traces of organic molecules
|
(ii) An organic solution of sugars and
amino acids is
translocated.
|
(iii) The movement is only upward.
|
(iii) The movement can be upward or
downward.
|
6.
What advantage over an aquatic organism does a terrestrial organism have with
regard to obtaining oxygen for respiration? (2 marks)
Ans:
In the aquatic habitat the concentration of oxygen is good up to a certain
depth only. Moreover, as oxygen is available as dissolved in water, so taking
oxygen from there is not a very efficient method to that.
In
terrestrial habitat oxygen is available in free form so it is easier to absorb
by organisms. This is more efficient so terrestrial organisms can facilitate
better utilization of food by way of respiration.
7. Differentiate
between osmoregulation and excretion?
Ans:
Excretion is the elimination of metabolic waste products from the body.
Osmoregulation
is regulating osmotic pressure of the body fluids by controlling the amount of
water and salts in the body
8.
Name any two autotrophic plants which also show heterotrophic mode of
nutrition. Why do they need to do so? (2 marks)
Ans:
All green plants are autotrophic but some of them also show heterotrophic
nutrition like Venus fly trap and pitcher plant as their nutritional
requirement is not fulfilled by photosynthesis like nitrogen and phosphorus as in
some areas, the soil is deficient in nitrogen.
9.
Name 3 kinds of blood vessels of human circulatory system. Write
function of each. (3 marks)
Ans:
Arteries
|
Veins
|
Capillaries
|
|
1.
|
Carry Oxygen rich
blood from heart to all parts of the body.
|
Carry carbon dioxide
rich blood from all parts of the body back to the heart.
|
Capillaries act as a
link between arteries and veins.
|
2.
|
Since blood flow is
rapid and at high pressure they have thick elastic walls.
|
They have thin walls
|
Consists of just a
single layer of endothelial cells.
Water and other
small-molecule substances can pass through this wall.
|
3.
|
Valves are absent.
|
Valves present to
prevent back flow of blood.
|
No valves are found
|
10.
Name the constituents of blood. Why are WBC called ‘soldiers of the body’? (3
marks)
Ans:
The constituents of blood are
1.
Red blood cells or RBCs (erythrocytes)
2. White blood cells or WBCs (leucocytes)
3. Blood platelets (thrombocytes)
WBC is
called ‘soldiers of the body’ because
(a) White
blood cells protect the body from infec on. If germs like bacteria or viruses
enter the body, these cells surround the germs and destroy them by digesting.
(b) They also produce an bodies (blood
proteins) which kill the germs and foreign particles entering our body.
11.
Explain the process by which inhalation occurs during breathing in human
beings. (3 marks)
12.
Compare the functioning of alveoli in the lungs and nephrons in the kidneys
with respect to their structure and functioning. (3 marks)
Ans:
Alveoli
|
Nephron
|
Structure
|
Structure
|
(i) Alveoli are tiny balloon-like structures present inside the lungs.
|
(i) Nephrons are tubular structures present inside the kidneys.
|
(ii) The walls of the alveoli are one cell thick and it contains an extensive network of blood capillaries.
|
(ii) Nephrons are
made of glomerulus, bowman’s capsule, and a long renal tube. It also
contains a cluster of thin-walled capillaries.
|
Function
|
Function
|
(i) The exchange
of O 2 and CO2 takes place between the blood of the capillaries that
surround the alveoli and the gases present in the alveoli.
|
(i) The blood
enters the kidneys through the renal artery which branches into many
capillaries in the glomerulus. The water and solute are transferred to
the nephron at Bowman’s capsule. Then the filtrate moves through the
proximal tubule and then down into the loop of henle. From henle’s loop,
filtrate passes into the distal tubule and then to the collecting duct.
The collecting duct collects the urine from many nephrons and passes it
to the ureter. During the flow of filtrate, some substances such as
glucose, amino acids, and water are selectively re-absorbed.
|
(ii) Alveoli are the site of gaseous exchange.
|
(ii) Nephrons are the basic filtration unit.
|
13. Draw
a diagram of human alimentary canal showing duodenum, small intestine, liver
and pancreas. (3 marks)
OR
State
the two vital function of the human kidney.
Name
the procedure used in the working of artificial kidney. (3marks)
Ans:
(a) Function of Kidneys:
- Absorption of water and salt
- Removal of waste materials like urea, ammonia etc from blood
- Blood pressure control
(b)
Artificial kidney works on the principal of dialysis. It is also known as
haemodialysis.
In
hemodialysis, only a few drops of blood are allowed to flow, through a special
filter that removes wastes and extra fluid. The detoxified blood is then
returned to the body.
The
special filter used in dialysis consists of a number of tubes with
semi-permeable lining, suspended in a tank filled with the dialysis fluid.
14. What are the methods used by plants to get rid of
excretory products? (5 marks)
Plants
get rid of carbon dioxide and oxygen through diffusion. Old branches and leaves
are shed off when they become useless. Plants release some waste products
through roots also. Some waste products are deposited near bark as raisins or
gums.
15.
(i) State two structural differences between an artery and a vein. (5
marks)
(ii)
Name a non-nucleated cell present in human blood and state one functions of
this cell.
Ans:
RBC. Their chief function is to transport oxygen to different parts of the bod
(iii)
Draw a labelled diagram of human heart.