Question 1

Question 1(i)The soluble protein present in the blood plasma which is responsible for blood clotting is :ProthrombinFibrinThrombinFibrinogen

Accepted Answer

FibrinogenReason — Thrombin reacts with soluble fibrinogen in presence of calcium ions to form insoluble fibrin.

Question 2

Question 1(ii)The abnormal rise of erythrocytes in blood is :ErythropeniaPolycythaemiaLeukopeniaLeukemia

Accepted Answer

PolycythaemiaReason — Polycythaemia is a condition of abnormal rise of erythrocytes in blood.

Question 3

Question 1(iii)The part of nephron where ultrafiltration occurs :Bowman’s capsuleVasa rectaGlomerulusLoop of Henle

Accepted Answer

GlomerulusReason — Glomerulus has afferent arteriole and narrow efferent arteriole due to which high pressure is exerted and ultrafiltration occurs.

Question 4

Question 1(vi)The fibrous sheet which connects into cerebral hemisphere is :Corpus luteumCerebellumPonsCorpus callossum

Accepted Answer

Corpus callossumReason — Corpus callossum is a sheet of fibres connecting the two cerebral hemispheres.

Question 5

Question 1(vii)Cinematography makes use of :AccommodationAfter imageAdaptationAll of these

Accepted Answer

After imageReason — The image seen by us persists for one-tenth of a second. This is known as after image. In movies, pictures are projected on a screen at the rate of about 24 pictures per second which gives an illusion of life-like continuous movement.

Question 6

Question 1(xii)The statistical study of human population is called :Population densityDemographyMortalityNatality

Accepted Answer

DemographyReason — Demography is the term given to statistical study of human population.

Question 7

Question 1(xiii)The basic structural unit of human chromosome is :NucleotideNucleic acidNucleosideNucleosome

Accepted Answer

NucleosomeReason — Nucleic acid along with histone protein form nucleosome which is the basic structural unit of human chromosome.

Question 8

Question 1(xiv)The phenotypic ratio in F2 generation of a monohybrid cross is :1:31:2:13:19:3:3:1

Accepted Answer

3:1Reason — The phenotypic ratio in F2 generation of a monohybrid cross is 3:1 because of segregation of genes which leads to recessive homozygous condition.

Question 9

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 (highlighted).(i) Prophase, Telophase, Anaphase, Metaphase(ii) Kidney, Urethra, Ureter, Urinary bladder(iii) Right ventricle, Lungs, Pulmonary vein, Pulmonary artery(iv) Ear pinna, Membranous labyrinth, Ear ossicles, Auditory canal(v) Stimulus, Effector, Receptor, CNS.

Accepted Answer

(i) Prophase → Metaphase→ Anaphase→ Telophase(ii) Kidney → Ureter→ Urinary bladder→ Urethra(iii) Right ventricle → Pulmonary artery→ Lungs→ Pulmonary vein(iv) Ear pinna → Auditory canal→ Ear ossicles→ Membranous labyrinth(v) Stimulus → Receptor→ CNS→ Effector

Question 10

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) Endosmosis1. Hydathodes(ii) Exosmosis2. Hydrophilic(iii) Guttation3. Hypertonic solution(iv) Cellulose4. Hydrostatic pressure(v) Ultrafiltration5. Hypotonic solution 6. Haematuria 7. Haemin

Accepted Answer

Column IColumn II(i) Endosmosis5. Hypotonic solution(ii) Exosmosis3. Hypertonic solution(iii) Guttation1. Hydathodes(iv) Cellulose2. Hydrophilic(v) Ultrafiltration4. Hydrostatic pressure

Question 11

Question 2(d)Choose the odd one out from the following terms and name the category to which the others belong :(i) Chloroplast, Chromoplast, Chromosome, Leucoplast(ii) Adenine, Adrenaline, Thymine, Cytosine(iii) Thrombokinase, Thrombocytes, Leucocytes, Erythrocytes(iv) Urea, Uric acid, Urochrome, Ammonia(v) Wisdom teeth, Oesophagus, Vermiform appendix, Ear pinna

Accepted Answer

(i) Odd one : ChromosomeChloroplast, Chromoplast, Leucoplast — Plastids(ii) Odd one : AdrenalineAdenine, Thymine, Cytosine — Nitrogenous base(iii) Odd one : ThrombokinaseThrombocytes, Leucocytes, Erythrocytes — Blood cells(iv) Odd one : UrochromeUrea, Uric acid, Ammonia — Constituents of urine(v) Odd one : OesophagusWisdom teeth, Vermiform appendix, Ear pinna — Vestigial organs

Question 12

Question 3(d)What is the significance of transpiration. State in two points.

Accepted Answer

Significance of transpiration:Maintains the temperature of plant.Transpirational pull helps in absorption of water and mineral by roots.

Question 13

Question 3(e)The figures given below depict a phenomenon of the plants. Study the figure and answer the questions.(i) Name and define the phenomenon.(ii) Name the structure shown as X and Y in the figure (A) and (B), respectively.(iii) Write the functions performed by the structures X and Y.

Accepted Answer

(i) Thigmotropism is the phenomenon depicted. It is the directional growth movement of plant parts in response to touch stimulus.(ii) X → Stem tendril, Y → Leaf tendril(iii) Stem tendrils (X) and leaf tendrils (Y) enable the plant to climb up a support.

Question 14

Question 4(c)What do you mean by 'Adaptation of Eye' ? Write its two kinds.

Accepted Answer

Adaptation of the eye is the process by which the eyes adjust to changes in light levels, allowing us to see clearly in both bright and dim environments. Its two kinds are:Light adaptationDark adaptation

Question 15

Question 4(d)Write two important functions of human ovaries.

Accepted Answer

Two important functions of human ovaries are:They produce eggs.They secrete the reproductive hormones, Oestrogen and Progesterone.

Question 16

Question 4(e)Given below is a figure of the internal structure of an organelle found in plants cells. Study the figure and answer the following questions :(i) Identify the organelle and name the physiological process that occurs in this organelle.(ii) Label the guidelines 1 and 3 of the figure.(iii) Write a well balanced equation for the above metabolic process.

Accepted Answer

(i) The given organelle is Chloroplast. Photosynthesis occurs in this organelle.(ii) The labelled guidelines are:1 → Stroma2 → Thylokoid3 → Granum(iii) Balanced chemical equation representing the process of photosynthesis is given below:6CO2+12H2O→chlorophylllight energyC6H12O6+6H2O+6O2↑6	ext{CO}_2 + 12	ext{H}_2	ext{O} \xrightarrow[	ext{chlorophyll}]{	ext{light energy}} 	ext{C}_6	ext{H}_{12}	ext{O}_6 + 6	ext{H}_2	ext{O} + 6	ext{O}_2 \uparrow6CO2​+12H2​Olight energychlorophyll​C6​H12​O6​+6H2​O+6O2​↑

Question 17

Question 5(a)Define - 'Pollution'

Accepted Answer

Pollution is the addition of any such constituent to air, water or land which deteriorates the natural quality of the environment.

Question 18

Question 5(e)Draw a neat and labelled diagram of an animal cell showing the anaphase stage of mitosis with two pairs of chromosomes.

Accepted Answer

Below labelled diagram shows the anaphase stage of mitosis in an animal cell with two pairs of chromosomes:

Question 19

Question 6(a)Define - 'Population'

Accepted Answer

A population is defined as a group of individuals of the same species living and interbreeding within a given area.

Question 20

Question 6(e)Study the diagram given below and answer the questions that follow:(i) Name the cells of the pancreas that produce glucagon and insulin.(ii) State the main function of glucagon and insulin.(iii) What is the technical term for the cells of the pancreas that produce hormones?

Accepted Answer

(i) Beta cells and Alpha cells of the islets of Langerhans produce Insulin and Glucagon, respectively.(ii) The main function of Glucagon is to raise the blood glucose levels by stimulating the breakdown of glycogen to glucose in the liver.The main function of Insulin is to maintain the levels of glucose (sugar) in the blood.(iii) The Islets of Langerhans

Model Question Paper 1

Section A

Section B