Q: Question 3(iv)Write the overall chemical equation for Photosynthesis.

6CO2+12H2O→chlorophylllight energyC6H12O6+6H2O+6O2↑6\text{CO}_2 + 12\text{H}_2\text{O} \xrightarrow[\text{chlorophyll}]{\text{light energy}} \text{C}_6\text{H}_{12}\text{O}_6 + 6\text{H}_2\text{O} + 6\text{O}_2 \uparrow6CO2+12H2Olight energychlorophyllC6H12O6+6H2O+6O2↑

Question 1

Question 1(ii)The antiseptic present in tears:IodineHydrogen peroxideLysozymeLysosome

Accepted Answer

LysozymeReason — Lysozyme is an enzyme that plays a role in the immune system, particularly in defense against bacterial infections.

Question 2

Question 1(iii)Assertion (A) : The foetus respires but does not breathe.Reason (R): The maternal blood supplies oxygen to the foetus through placenta.A is True and R is FalseA is False and R is TrueBoth A and R are TrueBoth A and R are False

Accepted Answer

Both A and R are TrueReason — Respiration refers to the metabolic process by which cells break down nutrients (such as glucose) to produce energy, usually in the form of ATP (adenosine triphosphate). The foetus obtains oxygen and nutrients from the mother through the placenta.

Question 3

Question 1(v)The two cerebral hemispheres are joined by a sheet of fibres called:PonsCorpus luteumHypothalamusCorpus callosum

Accepted Answer

Corpus callosumReason — The corpus callosum is a thick band of nerve fibers that connects the two cerebral hemispheres of the brain. It facilitates communication between the left and right hemispheres.

Question 4

Question 1(vii)Assertion (A): Rods and Cones are photoreceptors in the sclera of eyeball.Reason (R): Rods are sensitive to dim light.A is True and R is False.A is False and R is True.Both A and R are True.Both A and R are False.

Accepted Answer

A is False and R is TrueReason — Rods and cones are located in the retina, not the sclera.

Question 5

Question 1(viii)Priya tried to match the hormones with their effect on the human body. She tabulated the pairs as follows:HormoneEffect on the bodyPStimulates conversion of Glycogen to GlucoseQReabsorption of water by the Nephrons.Identify the correct pair of hormones.P- Insulin, Q- GlucagonP- Adrenaline, Q- OxytocinP- Glucagon, Q- VasopressinP- Vasopressin, Q- Adrenaline

Accepted Answer

P- Glucagon, Q- VasopressinReason — Glucagon is a hormone produced by the pancreas that stimulates the conversion of glycogen (stored form of glucose in the liver) to glucose. Vasopressin, also known as antidiuretic hormone (ADH), is produced by the posterior lobe of the pituitary gland. It acts on the kidney increasing reabsorption of water by the nephrons.

Question 6

Question 1(xii)Rahul inserted a hairpin into his right ear to remove ear wax. He felt a sudden sharp pain with loss of hearing. This was due to:Rupture of eardrumRupture of vestibuleRupture of corneaRupture of pinna

Accepted Answer

Rupture of eardrumReason — Rupture of the eardrum, also known as tympanic membrane perforation, is a condition where there is a tear or hole in the thin membrane that separates the outer ear from the middle ear.

Question 7

Question 1(xiv)A biology teacher asked her students to give two examples of vestigial organs in the human body.Raj said: Wisdom teeth and PinnaSonu said: Body hair and large intestineLata said: Vermiform appendix and wisdom teethAbhay said: Pinna and OssiclesWho were correct?Abhay and SonuSonu and LataRaj and LataAbhay and Raj

Accepted Answer

Raj and LataReason — Wisdom teeth, Pinna and Vermiform appendix are vestigial organs whereas large intestine, ossicles and body hairs perform important functions in human body, hence, are not vestigial organs.

Question 8

Question 2(ii)Given below is the transverse section of the spinal cord. Read the information below the diagram and fill in the blanks:The spinal cord extends from the medulla oblongata of the brain and runs down through the whole length of the vertebral column. The spinal cord is covered by the meninges. It conducts impulses from the skin and muscles to the brain. It also conducts impulses from the brain to the muscles of the trunk and limbs.The spinal cord is a part of the (a) ............... Nervous System. The grey matter in the picture given above consists of (b) ............... while the white matter consists of (c) ............... . The spinal cord is concerned with the (d) ............... actions below the neck. (e) ............... is the bony structure that protects the spinal cord.

Accepted Answer

The spinal cord is a part of the (a) Central Nervous System. The grey matter in the picture given above consists of (b) cytons while the white matter consists of (c) axons. The spinal cord is concerned with the (d) reflex actions below the neck. (e) Vertebral column is the bony structure that protects the spinal cord.

Question 9

Question 3(i)Explain the term — Active transport.

Accepted Answer

Active transport is the passage of a substance (salt or ion) from its lower to higher concentration through a living cell membrane using energy from the cell.

Question 10

Question 3(iv)Write the overall chemical equation for Photosynthesis.

Accepted Answer

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 11

Question 4(i)Why is Adrenaline called ‘The Emergency Hormone"?

Accepted Answer

Adrenaline is known as the Emergency hormone because it prepares the body to meet any emergency situation, for "fight" i.e. to face danger or for "flight" i.e. to run away from it. Extra energy and strength is provided to the body in that situation. It stimulates the sympathetic nervous system. When excited or angry, the adrenal medulla produces a lot of Adrenaline preparing the body for any emergency.

Question 12

Question 4(iv)State two objectives of Swachh Bharat Abhiyan.

Accepted Answer

Two objectives of Swachh Bharat Abhiyan are:To eliminate open defecation: The mission aims to ensure that all households have access to toilets and promote the construction and use of sanitary latrines.To promote cleanliness and hygiene: It seeks to create awareness about sanitation and cleanliness practices, improve waste management systems, and maintain cleanliness in public spaces.

Question 13

Question 4(v)Draw a neat, labelled diagram of a root hair.

Accepted Answer

Labelled diagram of a root hair is given below:

Question 14

Question 5(i)Mention one characteristic of roots for absorbing water from the soil.

Accepted Answer

One characteristic of roots for absorbing water from the soil is presence of thin cell walls in root hairs. This allows easy entry of water in the root hairs from the soil.

Question 15

Question 5(iii)State the difference between Micturition and Parturition.

Accepted Answer

MicturitionParturitionMicturition refers to the process of urination, which is the expulsion of urine from the urinary bladder through the urethra to the outside of the body.Parturition refers to the expulsion of the fully developed foetus from the uterus at the end of gestation.

Question 16

Question 5(v)Study the picture given below and answer the questions:(a) How does water get polluted?(b) What is the effect of water pollution on human life?(c) Mention one control measure to stop the pollution of water bodies.

Accepted Answer

(a) Water gets polluted due to:Factories and industrial facilities releasing pollutants such as chemicals, heavy metals, and toxins into water bodies.Pesticides, herbicides, and fertilizers used in agriculture can wash into rivers, lakes, and streams through runoff, especially after heavy rainfall.(b) Contaminated water can carry pathogens such as bacteria, viruses, and parasites that cause waterborne diseases like cholera, dysentery, hepatitis A, and giardiasis. Long-term exposure to polluted water containing harmful chemicals, such as heavy metals (e.g., lead, mercury) and industrial pollutants, can result in chronic health issues.(c) By ensuring that all industrial, agricultural, and municipal wastewater is properly treated before being released into water bodies, harmful pollutants and contaminants can be significantly reduced.

Question 17

Question 6(i)State Mendel’s Law of Segregation

Accepted Answer

During the formation of gametes (sperm or eggs), the two alleles for a given gene separate, or segregate, so that each gamete carries only one allele for each gene. When gametes fuse during fertilization, the resulting offspring inherits one allele from each parent, restoring the diploid number of alleles for that gene.

Question 18

Question 6(iii)Differentiate between the terms Phenotype and Genotype.

Accepted Answer

PhenotypeGenotypeThe phenotype is the observable physical or physiological traits of an organism resulting from the interaction of its genotype with the environment.The genotype refers to the genetic makeup of an organism, specifically the alleles or combinations of alleles it possesses for a particular gene or set of genes.It represents the underlying genetic code that contributes to an organism’s traits.It represents how the genetic information is expressed in the organism.

Question 19

Question 6(iv)What is the significance of Testes being placed in Scrotal sacs?

Accepted Answer

Testes are responsible for the production of male gametes i.e., sperms. The normal body temperature does not allow 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.

Question 20

Question 6(v)Draw a neat, labelled diagram of a human sperm.

Accepted Answer

Labelled diagram of a human sperm is shown below:

Solved 2025 Specimen Paper ICSE Class 10 Biology

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