Question 1

Question 1(i)A cell has 4 pairs of chromosomes. After mitotic division, the number of chromosome pairs in the daughter cells would be :814448

Accepted Answer

4Reason — After mitotic division, the number of chromosome pairs in the daughter cells remain same.

Question 2

Question 1(vi)With increase in atmospheric humidity, the rate of transpiration will :Increase slowlyRemain the sameDecreaseIncrease rapidly

Accepted Answer

DecreaseReason — The rate of transpiration depends on concentration of water vapour in surrounding. It is higher when the surrounding is drier.

Question 3

Question 1(vii)In the process of photosynthesis, the substance which is reduced is :GlucoseOxygenWaterCarbon dioxide

Accepted Answer

Carbon dioxideReason — In the process of photosynthesis, the substance which is reduced is Carbon dioxide as oxygen is removed from it and the carbon is used in the formation of glucose.

Question 4

Question 1(xi)Which part of the brain controls and coordinates muscular activity and balance of the body ?CerebrumPonsCerebellumDiencephalon

Accepted Answer

CerebellumReason — Cerebellum has controls and coordinates muscular activity and balance of the body.

Question 5

Question 2(a)Name the following :(i) The number of deaths per 1000 of population per year.(ii) The liquid waste material produced by factories.(iii) The scattered golgi bodies in plant cells.(iv) The structures which help in the formation of spindle fibres in plant cells during cell division.(v) The part of inner ear responsible for dynamic balance.

Accepted Answer

(i) Mortality rate(ii) Effluent(iii) Dictyosomes(iv) Microtubules(v) Semi-circular canals

Question 6

Question 2(b)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.(i) Soil water, Xylem, Pericycle, Root hair(ii) Xylem vessels, Stoma, Mesophyll, Sub-stomatal space(iii) Light energy, Thylakoid, Glucose, Splitting of water molecules(iv) Glomerulus, Collecting duct, Loop of Henle, Distal convoluted tubule(v) Conjunctiva, Retina, Vitreous humour, Cornea

Accepted Answer

(i) Soil water → Root hair → Pericycle → Xylem(ii) Xylem vessels → Mesophyll → Sub-stomatal space → Stoma(iii) Light energy → Thylakoid → Splitting of water molecules → Glucose(iv) Glomerulus → Loop of Henle → Distal convoluted tubule → Collecting duct(v) Conjunctiva → Cornea → Vitreous humour → Retina

Question 7

Question 2(c)Match the items given in column I with the most appropriate ones in column II and rewrite the correct matching pairs.Column IColumn II(i) ThylakoidsPhotorespiration(ii) Starch formationPhoto-chemical phase(iii) ATPPhotosynthesis(iv) AutotrophsPhotolysis of water(v) Light reactionPolymerisation Phagocytosis Phosphorylation

Accepted Answer

Column IColumn II(i) ThylakoidsPhotolysis of water(ii) Starch formationPolymerisation(iii) ATPPhosphorylation(iv) AutotrophsPhotosynthesis(v) Light reactionPhoto-chemical phase

Question 8

Question 2(d)Choose the odd one out from the following terms and name the category to which the others belong :(i) Uterine tubes, Seminiferous tubule, Epididymis, Interstitial cells(ii) Progesterone, Testosterone, Oestrogen, Prolactin(iii) Conjunctiva, Cornea, Cochlea, Choroid(iv) Cell wall, Visking bag, Cellophane paper, Parchment paper(v) Simple goitre, Myxoedema, Cretinism, Acromegaly

Accepted Answer

(i) Odd one — Uterine tubesSeminiferous tubule, Epididymis, Interstitial cells — Parts of Testis(ii) Odd one — TestosteroneProgesterone, Oestrogen, Prolactin — Female hormones(iii) Odd one — CochleaConjunctiva, Cornea, Choroid — Parts of Eye(iv) Odd one — Cell wallVisking bag, Cellophane paper, Parchment paper — Semi-permeable membranes(v) Odd one — AcromegalySimple goitre, Myxoedema, Cretinism — Hypothyroidism

Question 9

Question 3(b)Distinguish between sympathetic and parasympathetic nervous system on the basis of function.

Accepted Answer

Sympathetic nervous system prepares the body for violent action against abnormal conditions while the parasympathetic nervous system is more concerned with re-establishing normal conditions after the violent act is over.

Question 10

Question 3(c)What is lysozyme? Write its one important role.

Accepted Answer

Lysozyme is an enzyme having antiseptic property and it is present in tears. It protects the eyes from bacterial infections.

Question 11

Question 3(d)Write two significant roles of Hepatic Portal system.

Accepted Answer

Two significant roles of Hepatic Portal system are:Glycogenesis — Excess sugar is converted and stored in the liver in the form of glycogen.Detoxification — If any poisonous and harmful material is absorbed through food, they are detoxified in the liver.

Question 12

Question 3(e)Given below is a simplified diagrammatic representation of a defect of the human eye. Study the figure and answer the following questions.(i) Identify the defect (technical term).(ii) Mention two reasons for the above defect.(iii) Draw a neat and labelled diagram for the “correction of the above mentioned defect” by using a lens. You must mention the name of the lens used.

Accepted Answer

(i) Hyperopia(ii) Two reasons for the above defect are:Shortening of the eyeballLens is too flat(iii) Convex lens is used for the correction of Hyperopia. The diagram is shown below:

Question 13

Question 4(c)What are the two important roles of the plant hormone ‘Gibberellins’ ?

Accepted Answer

Two important roles of the plant hormone ‘Gibberellins’ are:Promote the growth of internodes by cell elongation.Break seed dormancy and initiate germination.

Question 14

Question 4(d)Write two important functions of Amniotic fluid.

Accepted Answer

Two important functions of Amniotic fluid are:Protects the embryo from physical damage by jerks or mechanical shocks.Keeps an even pressure all around the embryo.

Question 15

Question 4(e)The diagram given alongside is the longitudinal section of a human kidney. Study the diagram and answer the questions that follow.(i) Label the parts numbered 1 and 3.(ii) Name the fluid that passes down from the part numbered as 4. Also write its main nitrogenous constituent.(iii) Why does part 2 show a striped appearance?

Accepted Answer

(i) The parts labelled 1 and 3 are:1 → Cortex3 → Pelvis(ii) The fluid is urine. Its main nitrogenous constituent is Urea.(iii) Henle's loops and collecting ducts lie in the medulla of kidneys giving it a striped appearance.

Question 16

Question 5(b)Differentiate between biodegradable and non-biodegradable wastes.

Accepted Answer

Biodegradable wasteNon-biodegradable wasteBiodegradable wastes are substances which can be broken down by microorganisms into harmless and non-toxic substances.Non-biodegradable wastes are substances which cannot be broken down by microorganisms.Examples: Leaves, dung.Examples: Plastic, glass.

Question 17

Question 5(c)What is placenta? Write its one important role.

Accepted Answer

Placenta is the disc like structure attached to the uterine wall connecting the foetus to the uterus. It helps the foetus to get oxygen and nutrients from mother.

Question 18

Question 5(d)Make a Punnett square for the cross between two heterozygous axial flowers. Write the Genotypic and Phenotypic ratios of the offspring.

Accepted Answer

AaAAAAaaAaaaGenotypic Ratio → 1:2:1 Phenotypic Ratio → 3:1

Question 19

Question 5(e)Given below is the diagram of a human heart showing one phase of contraction. Study the same and answer the following questions.(i) Label the parts numbered as 3 and 4.(ii) What is the main difference between the blood flowing through the parts numbered as 1 and 2 ?(iii) Write one important role of the part numbered as 5.

Accepted Answer

(i) Parts numbered 3 and 4 are:3 → Bicuspid valve4 → Aortic Semilunar valve(ii) Blood flowing through 1 (Pulmonary artery) is deoxygenated. Blood flowing through 2 (Aorta) is oxygenated.(iii) Part 5 is pulmonary semilunar valve. It prevents backflow of blood into ventricles.

Question 20

Question 6(e)The diagram given alongside represents a stage during the mitotic cell division. Study the same and answer the following questions.(i) Identify the stage. Give reasons to support your answer.(ii) Label the parts numbered 1 and 2.(iii) Draw a neat and labelled diagram of the stage that comes before the stage shown in the figure.

Accepted Answer

(i) The stage shown is Telophase as the daughter chromosomes have reached opposite poles, spindle fibres have started to disappear, nuclear membrane is formed and the cleavage furrow has started deepening.(ii) Parts numbered 1 and 2 are:1 → Chromosome2 → Nuclear membrane(iii) Anaphase is the stage that comes before Telophase. Diagram showing anaphase is given below:

Model Question Paper 2

Section A

Section B