Question 1

Question 1(vi)Assertion(A): Loss of water as tiny drops along the margins of the tips of leaves, especially in the early morning is called guttation.Reason: Excessive root pressure is responsible for guttation.Both A and R are trueBoth A and R are falseAis true and R is falseA is false and R is true

Accepted Answer

Both A and R are trueReason — Guttation is loss of water as tiny drops from hydathodes of leaves. It occurs due to high root pressure.

Question 2

Question(xi)Why should we conserve forests and wildlife?To maintain balanceTo protect biodiversityTo continue food chainAll of the above

Accepted Answer

All of the aboveReason — Conservation of forests and wildlife is done to maintain ecological balance by maintaining normal food chain and to protect biodiversity.

Question 3

Question(xiii)Blood flows in arteries in spurts and is under pressure. Which of the following reasons support this statement?P. Arteries transport blood from left ventricles.Q. Blood in left ventricle is at a high pressure.R. Arteries have valves.Only POnly QOnly P and QOnly P and R

Accepted Answer

Only P and QReason — Left ventricle pumps oxygenated blood at a high pressure to the rest of the body through arteries. This high-pressure blood is what causes the blood in the arteries to flow in a pulsatile manner, resulting in spurts.Statement R, "Arteries have valves," is not relevant to the blood flow in arteries. Valves are typically found in veins to prevent the backflow of blood, not in arteries.

Question 4

Question(xiv)The liquid which collects in the cavity of Bowman's capsule isconcentrated urineblood plasma minus blood proteinsglycogen and waterused bile for excretion

Accepted Answer

blood plasma minus blood proteinsReason — During ultrafiltration almost all the liquid part of the blood i.e plasma and organic/inorganic substances are collected in Bowman's capsule.

Question 5

Question 2(i)Name the following.(a) The instrument which is used to measure water uptake by the plant shoot during transpiration.(b) Movement of substances into root cells without the expenditure of energy.(c) The enzyme that is released from the injured cells and blood platelets of a wound.(d) The hormone produced when a plant is exposed to stress.(e) The part of the internal ear concerned with dynamic equilibrium of the body.

Accepted Answer

(a) Potometer(b) Passive transport(c) Thrombokinase(d) Abscisic Acid(e) Sensory cells in Semicircular canal

Question 6

Question 2(ii)Arrange and rewrite the terms in each group in correct order so as to be in a logical sequence beginning with the term that is underlined.(a) Cell wall, Nucleus, Nucleoplasm, Cell membrane, Cytoplasm(b) Australopithecus, Homo erectus, Cro-Magnon, Homo habilis, Homo sapiens sapiens(c) Head, Pulmonary artery, Right ventricle, Right auricle, Superior vena cava(d) Menstrual phase, Luteal phase Ovulatory phase, Follicular phase(e) Gamete formation, Zygote, Fertilisation, Embryo

Accepted Answer

(a) Cell wall, Cell membrane, Cytoplasm, Nucleus, Nucleoplasm,(b) Australopithecus, Homo habilis, Homo erectus, Cro-Magnon, Homo sapiens sapiens(c) Head, Superior vena cava, Right auricle, Right ventricle, Pulmonary artery.(d) Menstrual phase, Follicular phase, Ovulatory phase, Luteal phase(e) Gamete formation, Fertilisation, Zygote, Embryo

Question 7

Question 2(iv)Choose the odd one out from the following terms and name the category to which others belong.(a) Cortisol, Calcitonin, Cytokinin, Insulin(b) CO2, NO2, SO2, NH3(c) Law of dominance, Law of segregation, Law of Linkage, Law of independent assortment(d) Ovary, Fallopian tube, Ureter, Uterus(e) 'A' blood group, 'B' blood group, 'O' blood group, 'AB' blood group

Accepted Answer

(a) Odd one: CytokininCategory: Others are human hormones.(b) Odd one: NH3Category: Others are the type of vehicular air pollutants.(c) Odd one: Law of LinkageCategory: Others are Mendel's laws.(d) Odd one: UreterCategory: Others are parts of female reproductive system(e) Odd one: 'O' blood groupCategory: Others have antigen present on RBC in all blood groups.

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 IIMyxoedemaHypersecretion of adrenalineDiabetes insipidusHyposecretion of adrenalinePituitary dwarfismHypersecretion of growth hormoneDiabetes mellitusHyposecretion of growth hormoneGigantismHyposecretion of insulin Hyposecretion of ADH Hyposecretion of thyroxine

Accepted Answer

Column IColumn IIMyxoedemaHyposecretion of thyroxineDiabetes insipidusHyposecretion of ADHPituitary dwarfismHyposecretion of growth hormoneDiabetes mellitusHyposecretion of insulinGigantismHypersecretion of growth hormone

Question 9

Question 3(i)Substances which are made up of cellulose or proteins are hydrophilic. What will happen to the wooden doors in rainy season?

Accepted Answer

The wooden doors will swell up during rainy season by absorbing moisture present in the air as cellulose being hydrophilic will imbibe (surface attraction) water.

Question 10

Question 3(ii)What is apical dominance? Name the hormone that controls it.

Accepted Answer

The phenomenon of the suppression of growth of lateral buds by apical buds is called apical dominance. It is controlled by auxin.

Question 11

Question 3(iii)Give differences between active transport and osmosis.

Accepted Answer

Active TransportOsmosisActive transport is the passage of a substance from its lower to higher concentration through a living cell membrane using energy from the cell.Osmosis is the movement of water molecules from their region of higher concentration to their region of lower concentration through a semi permeable membraneThere is expenditure of energy.There is no expenditure of energy.Occurs only when cell membrane is involved.Occurs when any semipermeable membrane like cell membrane or cellophane is involved.It occurs against concentration gradient.It occurs along the concentration gradient.

Question 12

Question 3(iv)What is sex-linked inheritance? Give one example.

Accepted Answer

Inheritance of any character whose gene are present on sex chromosomes (either X or Y) is called sex linked inheritance. For example : Hemophilia is X-linked genetic disorder.

Question 13

Question 3(v)Draw a clear diagram of human kidney and label following parts on it, renal capsule, cortex, hilum and ureter.

Accepted Answer

Diagram of human kidney with renal capsule, cortex, hilum and ureter labelled is shown below:

Question 14

Question 4(ii)Mention two reasons for the increase of population in India.

Accepted Answer

Two reasons for the increase of population in India are:Illiteracy — Most of the rural population which forms the bulk of our society is still illiterate, ignorant and superstitious. They also do not know the functioning of the human reproductive system.Traditional Beliefs — Among the people from lower strata of the society, children are regarded as a gift of God and a sign of prosperity. Therefore, they make no effort to avoid pregnancy.

Question 15

Question 4(iii)Differentiate between haemophilia and colour blindness.

Accepted Answer

Differences between haemophilia and colour blindness are:HaemophiliaColour blindnessHaemophilia is a genetic disorder in which blood does not clot properly due to lack of blood-clotting proteins.Colour blindness is a genetic disorder that affects a person's ability to perceive certain colors accurately.It can be fatal in case of excessive bleeding.It is not fatal.

Question 16

Question 4(iv)What is the function of coronary arteries? What will be their affect on human if they get blocked?

Accepted Answer

Coronary arteries supply blood to the heart muscles. When there is a blockage in any coronary artery or in any one or more of their branches, there is deadening of the corresponding area of heart muscles leading to myocardial infarction commonly referred to as a heart attack.

Question 17

Question 4(v)Draw a neat and labelled diagram to show hypermetropia.

Accepted Answer

Below labelled diagram shows hypermetropia:

Question 18

Question 5(ii)Enlist some of the consequences of population explosion.

Accepted Answer

Some of the consequences of population explosion are:Unemployment — Population explosion leads to unemployment as sufficient numbers of jobs are not available for the growing population.Increased Pollution — Due to population explosion, all kinds of pollutions (land, air, soil and water) increase causing degradation of environment and climatic conditions.

Question 19

Question 5(v)The diagram given below is a representation of K+ transport mechanism of stomatal opening and closing. Study the same and answer the questions that follows:(a) Name the cell labelled as A.(b) Mention the states of guard cells represented by B and C.(c) What causes closure of stomata during night?

Accepted Answer

(a) A represents epidermal cells.(b) The state of guard cell represented by B is turgid and the state of guard cell represented by C is flaccid.(c) During day, the guard cells have high concentration of K+ making it hypertonic. During night, the K+ ions are transported to epidermal cells due to which there is loss of water from guard cells making them flaccid. The stomata closes when guard cells are flaccid.

Question 20

Question 6(iii)A trait may be inherited but may not be expressed. Explain.

Accepted Answer

A dominant allele expresses itself while the recessive allele is masked in heterozygous condition. For example, when a plant with round (RR) seeds is crossed with a plant with wrinkled (rr) seeds, all F1 plants are with round seeds. Here, the genes are in heterozygous condition i.e., Rr. Allele 'r' is present but is not expressed as its effect is masked by allele 'R'. Therefore, we can say that a trait may be inherited but may not be expressed.

Solved Sample Paper 2

Section A

Section B