Solved 2013 Question Paper ICSE Class 10 Biology

Section I (40 Marks)

Question 1(a)

Name the following:

(i) The cell body of a nerve cell.

(ii) The waxy layer on the epidermis of the leaf meant to reduce transpiration.

(iii) A non-biodegradable pesticide.

(iv) The physical expression of genes in an individual.

(v) Knot-like mass of blood capillaries inside the bowman's capsule. [5]

Answer

(i) Cyton

(ii) Cuticle

(iii) DDT

(iv) Phenotype

(v) Glomerulus

Question 1(b)

State the exact location of the following:

(i) Chloroplast

(ii) Incus

(iii) Corpus callosum

(iv) Guard cells

(v) Pulmonary semilunar valve [5]

Answer

(i) Chloroplast are present in mesophyll cells located between the upper epidermis and the lower epidermis (i.e. in palisade cells and spongy cells) of leaves. They are also found in the guard cells of stomata and in the outer layers of young green stems.

(ii) Incus is located between Malleus and Stapes of ear ossicle which is found in the middle ear.

(iii) Corpus callosum is located between the two cerebral hemispheres.

(iv) Guard cells are located in Stomata.

(v) Pulmonary semilunar valves are located at the opening of the right ventricle into the pulmonary artery.

Question 1(c)

Given below are six sets with four terms each. In each set a term is an odd one and cannot be grouped in the same category to which the other three belong. Identify the odd one in each set and name the category to which the remaining three belong. The first one has been done as an example :

Example : Fructose, Sucrose, Glucose, Calcium.
Odd term: Calcium
Category: Carbohydrates

(i) Carbonic acid, Acetic acid, benzoic acid, boric acid.

(ii) Saliva, bile, sweat, tears.

(iii) Cretinism, Myxedema, Simple goitre, Acromegaly.

(iv) Sneezing, coughing, blinking, typing.

(v) Semicircular canals, Cochlea, tympanum, utriculus. [5]

Answer

(i) Odd term: Boric acid
     Category: Food Preservatives

(ii) Odd term: Bile
     Category: Germ killing secretions.

(iii) Odd term: Acromegaly.
     Category: Disorders of thyroid gland

(iv) Odd term: Typing
     Category: Unconditioned reflex

(v) Odd term: Tympanum
     Category: Parts of inner ear

Question 1(d)

Match the items in Column A with that which is most appropriate in Column B. Rewrite the matching pair. [5]

Answer

Question 1(e)

Choose the correct answer from the four options given below:

(i) The cell component visible only during cell division:

1. Mitochondria
2. Chloroplast
3. Chromosome
4. Chromatin

(ii) Pulse wave is mainly caused by the:

1. Systole of atria
2. Diastole of atria
3. Systole of the left ventricle
4. Systole of the right ventricle

(iii) The recessive gene is one that expresses itself in:

1. Heterozygous condition
2. Homozygous condition
3. F₂ generation
4. Y-linked inheritance

(iv) A gland which secretes both hormone and enzyme is the:

1. Pituitary
2. Pancreas
3. Thyroid
4. Adrenal

(v) The ventral root ganglion of the spinal cord contains cell bodies of the:

1. Motor neuron
2. Sensory neuron
3. Intermediate neuron
4. Association neuron [5]

Answer

(i) Chromosome

(ii) Systole of the left ventricle

(iii) Homozygous condition

(iv) Pancreas

(v) Association neuron

Question 1(f)

Given below is an example of certain structures and their special functional activities:
For example : Eye and vision.
On, a similar pattern complete the following:

(i) Neutrophils

(ii) Ureter

(iii) Neurotransmitters

(iv) Iris of the eye

(v) Placenta [5]

Answer

(i) Neutrophils : Phagocytosis

(ii) Ureter : Carries urine from Kidney to urinary bladder.

(iii) Neurotransmitters : Conduction of nerve impulse.

(iv) Iris of eye : Regulates amount of light entering the eye.

(v) Placenta : Transfer nutrients, oxygen, etc. from maternal blood to foetus.

Question 1(g)

The figure given below represents an experiment to demonstrate a particular aspect of photosynthesis. The alphabet 'A' represents a certain condition inside the flask.

(i) What is the aim of the experiment ?

(ii) Identify the special condition inside the flask.

(iii) Name an alternative chemical that can be used instead of KOH.

(iv) In what manner do the leaves 1 and 2 differ at the end of the starch test? [5]

Answer

(i) The aim of the experiment is to show that plants require Carbon dioxide (CO₂) for photosynthesis.

(ii) There is no Carbon dioxide (CO₂) present inside the flask because KOH absorbs it all.

The leaf inside the flask do not turn blue black when tested with iodine as the leaf inside the flask does not get atmospheric Carbon dioxide (CO₂) because KOH absorbs all the Carbon dioxide (CO₂) in the flask.

(iii) An alternative chemical that can be used instead of KOH is NaOH (Sodium hydroxide).

(iv) Leaf 1 does not turn blue black at the end of starch test because due to lack of Carbon dioxide (CO₂) inside the flask, it is not able to perform photosynthesis and produce starch. Leaf 2 on the other hand, gets atmospheric Carbon dioxide (CO₂)​. Hence, it is able to perform photosynthesis as it turns blue black after the starch test.

Question 1(h)

Given below are five groups of terms. In each group arrange and rewrite the terms in the correct order so as to be in a logical sequence.
For example : Implantation, Parturition, Ovulation, Gestation, Fertilization.
Answer: Ovulation, Fertilization, Implantation, Gestation, Parturition.

(i) Spongy cells, Upper epidermis, Stoma, Palisade tissue, Substomatal space.

(ii) Spinal cord, Motor neuron, Receptor, Effector, Sensory neuron.

(iii) Endodermis, Cortex, Soil water, Xylem, Root hair.

(iv) Metaphase, Telophase, Prophase, Anaphase, Cytokinesis.

(v) Intestine, Liver, Intestinal artery, Hepatic Vein, Hepatic Portal Vein. [5]

Answer

(i) Upper epidermis, Palisade tissue, Spongy cells, Substomatal space, Stoma.

(ii) Receptor, Sensory neuron, Spinal cord, Motor neuron, Effector.

(iii) Soil water, Root hair, Cortex, Endodermis, Xylem.

(iv) Prophase, Metaphase, Anaphase, Telophase, Cytokinesis.

(v) Intestinal artery, Intestine, Hepatic Portal Vein, Liver, Hepatic Veins.

Section II (40 Marks)

Question 2(a)

Given below is a diagram of the lateral section of a testis of a man. Study the same and answer the questions that follow:

(i) Label the parts numbered 1 to 4 of the diagram.

(ii) State the functions of the parts labelled 1 and 3.

(iii) What is the significance of the testes being located in the scrotal sac outside the abdomen?

(iv) What is the role played by the inguinal canal?

(v) What is semen? [5]

Answer

(i) The parts numbered 1 to 4 of the diagram are:

• 1 → Seminiferous tubules.
• 2 → Testicular lobes
• 3 → Epididymis
• 4 → Sperm duct/Vas deferens.

(ii) The functions of the parts labelled 1 and 3 are:

• Part 1 (Seminiferous tubules): Seminiferous tubules produce sperms by the process called spermatogenesis.
• Part 3 (Epididymis): The epididymis stores the sperms for some days for maturation and transport it to vas deferens.

(iii) Testes are responsible for the production of male gametes i.e. sperms. The normal body temperature does not allow for the maturation of the sperms. Being suspended outside the body cavity, the temperature in the scrotal sac is 2 to 3°C lower than that of the body which is the suitable temperature for the maturation of the sperms.
When it is too hot, the skin of the scrotum loosens so that the testes hang down away from the body. When it is too cold, the skin contracts in a folded manner and draws the testes closer to the body for warmth.

(iv) Inguinal canal allows the descent of testes along with their ducts, blood vessels and nerves, etc. The sperm duct from each Testis travels upwards into the abdomen passing through the Inguinal canal.

(v) Semen is the mixture of sperms and secretions from seminal vesicles, prostrate and cowper's glands. It is a milky fluid.

Question 2(b)

Give the biological/technical terms for the following :

(i) Chemical found in the blood which act against antigens.

(ii) A constituent that causes pollution.

(iii) The onset of menstruation in a young girl.

(iv) Structure which connects the placenta with the foetus.

(v) The fluid present between the layers of meninges.

(vi) Permanently open structures seen on the bark of an old woody stem.

(vii) The biological process which is the starting point of the food chain.

(viii) The change in an organism resulting due to stimulus.

(ix) An Antiseptic substance present in tears.

(x) A solution in which the relative concentration of water molecules and the solute on either side of the cell membrane is the same. [5]

Answer

(i) Immunoglobulins

(ii) Pollutant

(iii) Menarche

(iv) Umbillical cord

(v) Cerebrospinal fluid

(vi) Lenticles

(vii) Photosynthesis

(viii) Reflex action

(ix) Lysozyme

(x) Isotonic

Question 3(a)

Draw a diagram of the human eye as seen in a vertical section and label the parts which suits the following descriptions relating to the:

(i) photosensitive layer of the eye.

(ii) strucutre which is responsible for holding the eye lens in its position.

(iii) structure which maintains the shape of the eye ball and the area of no vision.

(iv) anterior chamber seen in front of the eye lens.

(v) outer most transparent layer seen in front of the eye ball. [5]

Answer

Labelled diagram of the human eye is given below:

Question 3(b)

Differentiate between the following pairs on the basis of what is mentioned in brackets :

(i) Photolysis and Photophosphorylation. (Definition)

(ii) Bicuspid valve and Tricuspid valve. (Function).

(iii) Vasectomy and Tubectomy. (Explain)

(iv) Cerebrum and Spinal cord. (Arrangement of nerve cells)

(v) Bowman's capsule and Malpighian capsule. (Parts included) [5]

Answer

(i) Difference between Photolysis and Photophosphorylation. (Definition)

(ii) Difference between Bicuspid valve and Tricuspid valve (Function).

(iii) Difference between Vasectomy and Tubectomy. (Explain)

(iv) Difference between Cerebrum and Spinal cord. (Arrangement of nerve cells)

(v) Difference between Bowman's capsule and Malpighian capsule. (Parts included)

Question 4(a)

Given below is a schematic diagram showing Mendel's Experiment on sweet pea plants having axial flowers with round seeds (AARR) and Terminal flowers with wrinkled seeds (aarr). Study the same and answer the questions that follow:

(i) Give the phenotype of F₁ progeny.

(ii) Give the phenotypes of F₂ progeny produced upon by the self-pollination of progeny.

(iii) Give the phenotypic ratio of F₂ progeny.

(iv) Name and explain the law induced by Mendel on the basis of the above observation. [5]

Answer

(i) The phenotype of F₁ progeny will be Axial Round as it is dominant phenotype.

(ii) The phenotypes of F₂ progeny will be Axial Round, Axial Wrinkled, Terminal Round and Terminal Wrinkled as in F₂ generation, recessive trait is also expressed.

(iii) Phenotypic ratio of F₂ progeny will be 9:3:3:1.

(iv) Above observation are based on Law of Independent Assortment. This law states that factors or genes controlling different characters assort independently without influencing each other during the formation of gametes.

Question 4(b)

Complete the following table by filling in the blanks from 1 to 10 with appropriate terms. [5]

Answer

Question 5(a)

The diagram given below represents the human heart in one phase of its functional activities. Study the same and answer the questions that follow:

(i) Name the phase.

(ii) Label the parts 1, 2, and 3

(iii) Which part of the heart is contracting in this phase? Give a reason to support your answer.

(iv) Draw well labelled diagrams of part 1 and 2 to show the structural differences between them. [5]

Answer

(i) Atrial systole.

(ii) The parts 1, 2, and 3 are:

• 1 → Pulmonary Artery
• 2 → Superior vena cava
• 3 → Aorta

(iii) Atrial muscles are contracting during this phase because tricuspid and bicuspid valves are open while semilunar valves at the roots of pulmonary artery and aorta are closed.

(iv) Part 1 is artery and part 2 is vein. Below diagram shows the structural differences between them:

Question 5(b)

Give biological reasons for the following :

(i) The wall of the ventricle is thicker than the auricles.

(ii) The renal cortex has a dotted appearance.

(iii) Wooden frames of doors get jammed during the monsoon season.

(iv) Throat infections can lead to ear infections.

(v) The hand automatically shows the direction to turn a cycle without thinking. [5]

Answer

(i) Ventricles have thicker walls than auricles because they have to pump blood to different organs and the pressure with which the blood flows through them is more than the auricles. Therefore, the walls are thicker in ventricles than in auricles.

(ii) As the cortex region contains numerous nephrons or kidney tubules, therefore, it shows a dotted appearance.

(iii) The wooden frames absorb moisture from the atmosphere due to imbibition and swell up. This causes them to get jammed during the monsoon season.

(iv) The Eustachian tube is a part of the middle ear. It also connects the cavity of the middle ear to the throat. Hence, throat infections can lead to ear infections.

(v) It occurs due to conditioned reflexes. These reflexes are learned responses to stimuli acquired individually during the life of an organism.

Question 6(a)

The figure given below shows the epidermal cells of an onion bulb. This cell was then transferred to a drop of sugar solution.

(i) Draw a well labelled diagram of the epidermal cell as it would appear after immersion in a strong sugar solution.

(ii) What scientific term is used for the changes as shown in (i) above ?

(iii) What should be done to restore the cell back to its original condition ?

(iv) Give the scientific term for the recovery of the cell as a result of the step taken in (iii) above.

(v) Define the term osmosis. [5]

Answer

(i) Diagram of the plasmolysed epidermal cell after immersing it in a strong sugar solution is shown below:

(ii) Plasmolysis is technical term used for the above change.

(iii) To restore the cell back to its original condition, it must be placed in hypotonic solution immediately after it gets plasmolysed.

(iv) Deplasmolysis is technical term used for recovery of the cell as a result of the step taken in (iii) above.

(v) Osmosis is the movement of water molecules from their region of higher concentration (dilute solution or with a lower solute concentration) to their region of lower concentration (concentrated solution or with a higher solute concentration) through a semi permeable membrane.

Question 6(b)

Briefly explain the following terms:

(i) Genes.

(ii) Cytokinesis in plant cells.

(iii) Guttation.

(iv) Diabetes insipidus.

(v) Disinfectants. [5]

Answer

(i) Genes are specific sequences of nucleotides on a chromosome that encode particular proteins which express in the form of some particular feature of the body. They are the units of heredity which are transferred from parents to offsprings and are responsible for some specific characteristics of the offspring.

(ii) Cytokinesis is the division of cytoplasm. In plant cells, a cell plate appearing at the centre of the middle grows up to the periphery, splitting the cytoplasm into two and thus producing two new cells.

(iii) Guttation is the process by which drops of water appear along leaf margins due to excessive root pressure. It occurs early mornings or late nights.

(iv) Deficiency of Vasopressin (Anti-diuretic hormone or ADH) causes Diabetes Insipidus in which urination is frequent and copious, resulting in loss of water from the body and the person becomes thirsty.

(v) These are the chemicals that kill microbes once they come in contact with them, they are too strong to be used on the body. Example — Phenol and Cresol.

Question 7(a)

(i) Draw a well labelled diagram to show the anaphase stage of mitosis in a plant cell having four chromosomes.

(ii) State any two harmful effects of acid rain.

(iii) Expand the following biological abbreviations :

1. NADP
2. ACT [5]

Answer

(i) Diagram showing the anaphase stage of mitosis in a plant cell having four chromosomes is shown below:

(ii) Two harmful effects of acid rain are:

1. Damage to vegetation by pollution of the soil.
2. Fish and other aquatic organisms are harmed due to increased acidity of water in lakes and rivers.

(iii) The full forms are mentioned below:

1. NADP — Nicotinamide Adenine Dinucleotide Phosphate
2. ACT — Adrenocorticotropin.

Question 7(b)

(i) List any two major activities of the Red Cross.

(ii) Write any two major reasons for the population explosion in the world.

(iii) Write the names of four nitrogenous bases in a DNA molecule. [5]

Answer

(i) Two major activities of the Red Cross are:

1. To extend relief and help to the victims of any calamity — fire, flood, famine, earthquakes etc.
2. To procure and supply blood for the victims of war and other calamities.

(ii) Two major reasons for the population explosion in the world are:

1. Better health care at all age groups and fewer deaths due to better medical aids.
2. Large scale immunization against communicable diseases.

(iii) The four nitrogenous bases in the DNA molecule are Guanine, Thymine, Adenine and Cytosine.