Question 1

Question 1(i)Loss of water as droplets from the hydathodes is called:TranspirationBleedingGuttationEvaporation

Accepted Answer

GuttationReason — Guttation is the loss of water as droplets along the margins of leaves through hydathodes.

Question 2

Question 1(vi)Assertion (A): There is frequent urination in summer than in winter.Reason (R): In summer we lose a lot of water as sweat, so the kidneys reabsorb more water. Hence, urine formed is less in summer than in winter.Both A and R are TrueBoth A and R are FalseA is True and R is FalseA is False and R is True

Accepted Answer

A is False and R is TrueReason — Urination is not so frequent in summers because more water is lost due to sweating

Question 3

Question 1(vii)The age restrictions for marriage for boys and girls by law in India is:Boys 18 years, Girls 21 yearsBoys 17 years, Girls 16 yearsBoys 21 years, Girls 18 yearsBoys 20 years, Girls 17 years

Accepted Answer

Boys 21 years, Girls 18 yearsReason — The age restrictions for marriage for boys and girls by law in India is 21 years and 18 years, respectively.

Question 4

Question 1(xiv)The ground substance present in chloroplast is:StomaStromaGranaThylakoids

Accepted Answer

StromaReason — The ground substance present in chloroplast is stroma into which the thylakoids are embedded.

Question 5

Question 2(i)Name the following:(a) The respiratory pigment in Erythrocytes.(b) The tissue that transports manufactured food from the leaves to all the parts of the plant.(c) The type of gene, which in the presence of a contrasting allele, is not expressed.(d) The duct which carries urine from the urinary bladder to outside the body.(e) The collective term for the protective membranes of the brain.

Accepted Answer

(a) Haemoglobin(b) Phloem(c) Recessive gene(d) Urethra(e) Meninges

Question 6

Question 2(iii)Fill in the blanks with suitable words:The technical term for short sightedness is (a) ............... . This defect is caused because the eyeball is (b) ............... from front to back or the lens is too (c) ............... . It can be corrected by using a suitable (d) ............... lens. The power of the lens is mentioned in (e) ............... .

Accepted Answer

The technical term for short sightedness is (a) myopia . This defect is caused because the eyeball is (b) lengthened from front to back or the lens is too (c) curved . It can be corrected by using a suitable (d) concave lens. The power of the lens is mentioned in (e) minus.

Question 7

Question 2(iv)Choose the odd one out from the following terms and name the category to which the others belong:(a) Newspapers, Vegetable peels, Electric bulbs, Animal excreta(b) Renal pelvis, Renal artery, Renal Cortex, Renal medulla(c) Urochrome, Urea, Keratin, Uric acid(d) Oval window, Cochlea, Auditory canal, Round window(e) ADH, TSH, ACTH, NADP

Accepted Answer

(a) Odd one: Electric bulbsNewspapers, Vegetable peels, Animal excreta : Biodegradable waste(b) Odd one: Renal arteryRenal pelvis, Renal Cortex, Renal medulla : Parts of Kidney(c) Odd one: KeratinUrea, Urochrome, Uric acid : Nitrogenous waste products that are excreted from the body(d) Odd one: Auditory canalOval window, Cochlea, Round window : Parts of inner ear(e) Odd one: NADPADH, TSH, ACTH : Hormones

Question 8

Question 2(v)Match the items given in Column I with the most appropriate ones in Column II and rewrite the correct matching pairs.Column IColumn IISpinal CordAdrenalinAdrenal medulla44Number of autosomes in manNephronsKidney46Adrenal cortexThyroxine Neurons Cortisones

Accepted Answer

Column IColumn IISpinal CordNeuronsAdrenal medullaAdrenalinNumber of autosomes in man44KidneyNephronsAdrenal cortexCortisones

Question 9

Question 3(ii)State Mendel's Law of Dominance.

Accepted Answer

Law of Dominance — Out of a pair of contrasting characters present together, only one is able to express itself while the other remains suppressed. The one that expresses is the dominant character and the one that is unexpressed is the recessive one.

Question 10

Question 3(iii)What are Homologous chromosomes?

Accepted Answer

The chromosomes that contain same genes in same order along their chromosomal arm are said to be homologous. They pair with each other during cell division.

Question 11

Question 3(iv)Differentiate between Phenotype and Genotype.

Accepted Answer

PhenotypeGenotypeThe observable characteristics which are genetically controlled is known as phenotype.Set of genes present in any organism is known as its genotype.Can be determined by observation.Can be determined by genotyping method.It consists of only expressed genes.It is formed by expressed and unexpressed genes.

Question 12

Question 3(v)Draw a neat, labelled diagram of a duplicated chromosome.

Accepted Answer

Labelled diagram of a duplicated chromosome is given below:

Question 13

Question 4(iii)Differentiate between Menarche and Menopause.

Accepted Answer

MenarcheMenopauseIt is the onset of menstruation in a young female at about the age of 13 years.It is the permanent stoppage of menstruation in females at about the age of 45 years.

Question 14

Question 4(iv)What is the significance of placenta in the growth of foetus?

Accepted Answer

The significance of placenta in the growth of foetus are:Placenta provides the foetus with oxygen and nutrients.Placenta also removes carbon dioxide and waste products of the foetus.

Question 15

Question 4(v)Draw a neat, labelled diagram of a human gamete that has the sex chromosome Y.

Accepted Answer

Sperm is the human gamete that can have sex chromosome Y. Its labelled diagram is shown below:

Question 16

Question 5(i)Explain the term — Photosynthesis.

Accepted Answer

Photosynthesis is the process by which living plant cells, containing chlorophyll, produce food substances (glucose and starch), from carbon dioxide and water, by using light energy and release oxygen as a by-product.

Question 17

Question 5(ii)Write the overall chemical equation of Photosynthesis.

Accepted Answer

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 18

Question 5(iii)A potted plant having variegated leaves was exposed to sunlight for 3 hours. One of the leaves was plucked and tested for starch. What will be your observation after the starch test?

Accepted Answer

After conducting the starch test, the green leaf portion turns blue, indicating starch presence, confirming photosynthesis due to chlorophyll. Non-green parts lack chlorophyll, don't photosynthesize, and show no starch-related colour change.

Question 19

Question 5(v)Study the diagram given below and answer the questions that follow:(a) Name the gas released when the setup was placed in sunlight.(b) Give an example of an aquatic plant that can be used in the above experiment.(c) What will happen if a pinch of Sodium bicarbonate is added to the water?

Accepted Answer

(a) Oxygen(b) Hydrilla(c) If a pinch of Sodium bicarbonate is added to the water the amount of carbon dioxide in water will increase. This will increase the rate of photosynthesis and hence the rate of evolution of oxygen will also increase.

Question 20

Question 6(ii)Differentiate between Karyokinesis and Cytokinesis.

Accepted Answer

KaryokinesisCytokinesisIt is the division of the nucleus.It is the division of the cytoplasm.It is the first division.It occurs after karyokinesis.It results in the formation of two nuclei.It results in the formation of two daughter cells.

Solved 2024 Specimen Paper ICSE Class 10 Biology

Section A

Section B