Solved Sample Paper 1

Section A

Question 1(i)

A plant hormone related with inhibition of senescence is

1. Auxins
2. GA
3. Cytokinins
4. ABA

Answer

GA

Reason — GA help in growth, initiate germination, breaks seed dormancy and inhibits senescence.

Question 1(ii)

How many autosomes does a human being have?

1. 34
2. 46
3. 54
4. 33

Answer

44

Reason — Humans have 22 pairs of autosomes and one pair of sex chromosome.

Question 1(iii)

Chromosomes are arranged at equatorial plate in

1. prophase
2. metaphase
3. anaphase
4. telophase

Answer

metaphase

Reason — In metaphase the chromosomes are arranged in equatorial plane and spindles attach to their centromeres.

Question 1(iv)

Which out of these can dissolve chlorophyll?

1. NaCl
2. Methylated spirit and alcohol
3. Sugar solution
4. Iodine solution

Answer

Methylated spirit and alcohol

Reason — Methylated spirit and alcohol dissolves chlorophyll from the leaves.

Question 1(v)

In humans, urea is formed in

1. ureter
2. liver
3. spleen
4. kidney

Answer

liver

Reason — The formation of urea occurs in liver and it is filtered out in the kidney.

Question 1(vi)

Assertion (A): Application of ethylene phytohormone induces fruit ripening.

Reason (R): Ethylene is the only hormone which is a gas at ordinary temperature.

1. Both A and R are true
2. Both A and R are false
3. A is true and R is false
4. A is false and R is true

Answer

Both A and R are true

Reason — Ethylene is a gaseous plant hormone that induces fruit ripening.

Question 1(vii)

Which of the following is an external factor that affects the rate of transpiration?

1. Leaf area
2. Age of plants
3. Water content of leaves
4. Carbon dioxide concentration

Answer

Carbon dioxide concentration

Reason — Carbon dioxide concentration above 0.03% cause stomatal closure and results in the decrease of transpiration.

Question 1(viii)

Ram went for his driving test. He has to answer many questions regarding this. He was able to give correct answers to all the questions, but was not able to read the numbers given in coloured circles. This was due to

1. colour blindness
2. myopia
3. hypermetropia
4. astigmatism

Answer

colour blindness

Reason — Colour blindness is a condition in which some people by birth cannot discriminate between certain colours such as red and green. This is due to a genetic defect.

Question 1(ix)

Which layer of eyeball is richly supplied with blood vessels for providing nourishment to the organ?

1. Sclerotic layer
2. Choroid
3. Retina
4. Cornea

Answer

Choroid

Reason — Choroid layer of eyeball is richly supplied with blood vessels for providing nourishment to it.

Question 1(x)

Extraordinary decrease in the number of leucocytes is called

1. leucopenia
2. leukemia
3. myopia
4. embolism

Answer

leucopenia

Reason — Leucopenia is an extraordinary decrease in white blood cell count.

Question 1(xi)

The passage of white blood corpuscles through unruptured wall of blood vessels is known as

1. diapedesis
2. haemopoiesis
3. phagocytosis
4. cyclosis

Answer

diapedesis

Reason — During any injury or infection the WBCs pass through the wall of blood vessel to reach the site of infection to fight bacteria. This process is referred to as diapedesis.

Question 1(xii)

The rate of comparison of transpiration from both surfaces of a dorsiventral leaf is measured using

1. Ganong's potometer
2. Darwin's potometer
3. Garreau's potometer
4. Farmer's potometer

Answer

Garreau's potometer

Reason — Garreau's potometer helps to compare the rate of transpiration from upper and lower surfaces of leaf.

Question 1(xiii)

X-ray machine operator have to take special care to avoid exposure of X-rays.

Which of the following reasons support this statement?

P. X-ray damage the body cells.
Q. Too frequent exposure may cause genetic variations, bone cancer etc.
R. Too much X-rays exposure are not harmful.

1. Only P
2. Only Q
3. Only P and Q
4. Only Q and R

Answer

Only P and Q

Reason — X-ray damages body cells and may cause genetic variations.

Question 1(xiv)

The average ratio of male to female individuals based on XX and XY type of sex-determination, in a human population is

1. 3:1
2. 1:3
3. 1:4
4. 1:1

Answer

1:1

Reason — XX and XY are equal giving a ratio 1:1.

Question 1(xv)

Harish was crossing the road when he suddenly slipped on a banana peel and fell on the road. After some time the inflamed region developed redness, swelling, pain with increased local heat.

Which of the following is/are involved in the process mentioned above?

(a) Leucocytes
(b) Erythrocytes
(c) Plasma
(d) Lymph

1. Only a
2. Only a and c
3. Only a, c and d
4. Only a, b and c

Answer

Only a

Reason — Inflammation occurs due to the reaction of tissues to injury and to localized invasion of germs. Here the leucocytes migrate through the walls of the blood vessels through diapedesis and fight against the disease causing germs.

Question 2(i)

Name the following.

(a) The layer of the eyeball that consists of two types of photoreceptor cells known as rods and cones.

(b) The phenomenon of gradual increase in the average temperature of the surface of the Earth.

(c) Thin, double layered membranous structure enclosing an embryo.

(d) The molecule through which genetic information is transferred from one generation to other.

(e) The process of RBCs (Red Blood Corpuscles) formation.

Answer

(a) Retina

(b) Global warming

(c) Amnion

(d) DNA

(e) Erythropoiesis

Question 2(ii)

Arrange and rewrite the terms in each group in the correct order so as to be in a logical sequence beginning with the term that is underlined.

(a) Eyeball, Retina, Sclerotic, Choroids

(b) Cuticle, Palisade tissue, Upper epidermis, Spongy parenchyma

(c) Injured tissue, Fibrinogen, Thromboplastin, Prothrombin

(d) Cortex, Endodermis, Xylem vessels, Pericycle

(e) Initial growth, Increase in size, Cell division, Chromosome replication.

Answer

(a) Eyeball, Sclerotic, Choroids, Retina

(b) Cuticle, Upper epidermis, Palisade tissue, Spongy parenchyma.

(c) Injured tissue, Thromboplastin, Prothrombin, Fibrinogen.

(d) Cortex, Endodermis, Pericycle, Xylem vessels.

(e) Initial growth, Chromosome replication, Increase in size, Cell division.

Question 2(iii)

Fill in the blanks with suitable words.

The inner ear or (a) ............... has two main parts (b) ............... and (c) ............... . The cochlea is (d) ............... and looks like a (e) ............... .

Answer

The inner ear or (a) membranous labyrinth has two main parts (b) cochlea and (c) semicircular canals . The cochlea is (d) spiral-shaped and looks like a (e) snail shell.

Question 2(iv)

Choose the odd one out from the following terms and name the category to which others belong

(a) Axon, Myelin sheath, Schwann cells, Synapse

(b) Seed shapes, Seed colour, Flower position, Inflorescence.

(c) Hypertension, Diarrhoea, Deafness, Irritation.

(d) Insulin, Glucagon, Thyroxine, Pepsin.

(e) Cretinism, Myxoedema, Goitre, Scurvy.

Answer

(a) Odd one: Synapse
Category: Others are parts of a nerve cell.

(b) Odd one: Inflorescence
Category: Others are traits studied by Mendel

(c) Odd one: Diarrhoea
Category: Others are effects of noise pollution.

(d) Odd one: Pepsin
Category: Others are hormones secreted by endocrine glands.

(e) Odd one: Scurvy
Category: Others are hormonal disorders

Question 2(v)

Match the items given in Column I with the most appropriate ones in Column II and rewrite the correct matching pairs

Answer

Section B

Question 3(i)

Potato cubes when placed in water, they become turgid. What will happen to the potato cubes when they are kept in sugar solution?

Answer

The potato cubes will become flaccid when kept in sugar solution due to exosmosis.

Question 3(ii)

Define tropic movement.

Answer

Growth movements occurring in response to unidirectional external stimuli in a plant part are called tropic movements.

Question 3(iii)

Mention two functions of abscisic acid.

Answer

Two functions of abscisic acid (ABA) are:

1. It accelerates senescence (ageing) and abscission of leaves.
2. It is a growth inhibitor and slows down the plant metabolism.

Question 3(iv)

What are the differences between menarche and menopause?

Answer

Differences between menarche and menopause are:

Question 3(v)

Draw a neat and labelled diagram showing the vertical section of a leaf.

Answer

Below labelled diagram shows the vertical section of a leaf:

Question 4(i)

Mention the exact location of amniotic fluid.

Answer

The exact location of amniotic fluid is between amnion and embryo.

Question 4(ii)

Differentiate between diastole and systole of cardiac cycle.

Answer

Differences between diastole and systole of cardiac cycle are:

Question 4(iii)

State two functions of pericardial fluid.

Answer

Two functions of pericardial fluid are:

1. It acts as a lubricant reducing friction during heart beats.
2. It protects the heart from shocks, jerks or any mechanical stress.

Question 4(iv)

Name the fluid being taken out through the syringe during amniocentesis process. How is this process helpful?

Answer

Amniotic fluid.

Amniocentesis process is helpful in pre-natal diagnosis of genetic diseases and other abnormalities.

Question 4(v)

Draw a neat and labelled diagram to show the internal view of testis.

Answer

Below labelled diagram shows the internal view of testis:

Question 5(i)

Define glomerular filtrate.

Answer

The fluid that enters the renal tubule after the process of ultrafiltration is called glomerular filtrate.

Question 5(ii)

Which gland secretes growth hormone? Also mention its effect on a person due to its deficiency as well as its excess secretion.

Answer

Pituitary gland secretes growth hormone. The deficiency of growth hormone causes dwarfism and its excess secretion causes gigantism.

Question 5(iii)

Who among the Dryopithecus and Ramapithecus was more man like?

Answer

Ramapithecus was more like man because Ramapithecus walked erect on its hindfeet and had few teeth and some fragments of jaw.

Question 5(iv)

A red coloured pigment A is found in the blood of vertebrates and a few invertebrates. A blue coloured respiratory pigment B is found in the blood of several invertebrates. Name A and B.

Answer

A → Haemoglobin

B → Haemocyanin

Question 5(v)

Given below is a diagram representing the structure of an ovum surrounded by a few sperm cells. Study the diagram and answer the questions that follows.

(a) Where does fertilisation, normally take place?

(b) Mention the chromosome number in egg and zygote in humans.

(c) What is the main function of corona radiata?

Answer

(a) The process of fertilisation takes place in the fallopian tube of females.

(b) The chromosome number in human egg (haploid) is 23 and zygote (diploid) is 46.

(c) The main function of corona radiata is to supply vital proteins to the ovum.

Question 6(i)

Give the exact location of occipital lobe of cerebral cortex.

Answer

The occipital lobe of cerebral cortex lies towards the back of the brain between parietal lobe and cerebellum.

Question 6(ii)

Differentiate between thigmotropic and chemotropic movement.

Answer

Differences between between thigmotropic and chemotropic movement are:

Question 6(iii)

Write any two postulates of Darwin's theory.

Answer

Two postulates of Darwin's theory are:

1. Overproduction — More offsprings are produced to increase their chances of survival.
2. Struggle for existence — Individuals multiply geometrically but space and food remain almost constant, resulting in a struggle for existence.

Question 6(iv)

Leaf of a green plant is called a food factory. Explain.

Answer

The process of photosynthesis is carried out primarily in leaves as they have chlorophyll and numerous stomata. The leaves trap maximum light energy and carry out gaseous exchange required for photosynthesis. Therefore, they are called food factory of plants.

Question 6(v)

Study the diagram given below and answer the questions that follows.

(a) Identify the structure.

(b) Write one difference in the composition of blood flowing through the blood vessels A or B.

(c) Which part of kidney contains freshly collected urine?

Answer

(a) Human excretory system.

(b) Blood flowing through blood vessel 'A' is impure and has more nitrogenous waste, while the blood flowing through blood vessel 'B' is filtered blood and has less nitrogenous waste.

(c) The renal pelvis contains the freshly collected urine.

Question 7(i)

Expand SAN.

Answer

Sino Atrial Valve.

Question 7(ii)

Give differences between interphase and M-phase.

Answer

Differences between interphase and M-phase are:

Question 7(iii)

What is mutation? Give one example.

Answer

Mutation is a sudden change in one or more genes, or in the number or in the structure of chromosomes that results in change of traits. For example, Sickle cell anaemia is a blood disease caused by a gene mutation.

Question 7(iv)

List any two effects of cortisone.

Answer

The two effects of cortisone are given below

1. It regulates mineral metabolism, specially Na+ and K+ ions.
2. It influences fat and protein metabolism.

Question 7(v)

Study the diagram given below and answer the questions that follows.

(a) Identify the parts indicated 1 and 2.

(b) Name the phenomenon shown in the diagram.

(c) Is the root hair cell unicellular or multicellular?

Answer

(a) Parts 1 and 2 are:

• 1 → Root hair
• 2 → Water molecules with soil particles

(b) Absorption of water by roots (Osmosis)

(c) Root hair is unicellular.

Question 8(i)

Define mitosis.

Answer

Mitosis is the cell division in which one parent cell divides into identical daughter cells.

Question 8(ii)

What are the long terms benefits of the Swachh Bharat Abhiyan?

Answer

Following are the long term benefits of Swachh Bharat Abhiyan:

1. It will make an Open Defecation Free (ODF) India by constructing toilets in rural India.
2. It will help achieve efficient solid and liquid waste management systems.
3. It will help in the beautification of cities.

Question 8(iii)

Migration is an important determinant of population change. Explain.

Answer

Migration changes not only the population size but also the population composition of urban and rural populations in terms of age and sex composition. In India, rural-urban migration has led to a continuous rise in the population of cities and towns.

Question 8(iv)

In the context of rising human population, name the six main resources that are under pressure.

Answer

The six main resources that are under pressure are:

1. Food
2. Forests
3. Water
4. Energy
5. Land
6. Minerals

Question 8(v)

The diagram given below represents an experiment to demonstrate a physiological process taking place in green plants. Answer the questions that follows.

(a) Label the parts A and B in the given figure.

(b) Name the physiological process being demonstrated.

(c) How could the rate of photosynthesis be increased in the given setup?

Answer

(a) Parts A and B are:

• A → Oxygen
• B → Aquatic plant / Hydrilla

(b) Photosynthesis.

(c) Rate of photosynthesis can be increased by adding a pinch of NaHCO₃, because it releases CO₂ in water.