Madhyamik Class 10 Life Science Solved Paper 2024

Madhyamik Class 10 Life Science Solved Paper 2024

LIFE SCIENCE

Time: 3 Hours and 15 Minutes

(First 15 Minutes for reading the question paper only, 3 Hours for writing) 

Full Marks: For Regular Candidates – 90

For External Candidates – 100

Regular candidates will answer questions from Groups A, B, C and D. External candidates will answer questions from Group E.

(Special Instructions for visually handicapped candidates)

Answer Question 4.1(A) instead of Question 4.1 in Group D. Instruction on how many questions from a group must be attempted is provided at the beginning of the group.

GROUP—A

(All Questions are Compulsory)

1. Choose the correct answer for each question and write it with its respective serial number:- [1×15=15]

Question 1.1

Select the correct pair from the following:

(a) Lens – Accomplishes accommodation by changing the curvature of its plane

(b) Retina – Holds the lens with the help of the suspensory ligament

(c) Cornea – Secretes aqueous humor

(d) Choroid – Helps to maintain the shape of the eyeball

Answer

Question 1.2

Consider the differences between hormone and nervous system mentioned below and choose which ones are correct:

(a) I, IV

(b) I, III

(c) II, III

(d) II, IV

Answer

Question 1.3

The natures of Biceps, Pyriformis and Latissimus dorsi muscles respectively are:

(a) Adductor, Extensor, Abductor

(b) Extensor, Flexor, Rotator

(C) Flexor, Rotator, Adductor

(d) Rotator, Abductor, Adductor

Answer

Question 1.4

In a certain phase of mitosis nuclear reticulum is reconstructed, nuclear membrane reappears, regeneration of nucleolus takes place and Spindle fibre disappears.

What is the phase ?

(a) Prophase

(b) Telophase

(c) Metaphase

(d) Anaphase

Answer

Question 1.5

Which of the following events occurs during sexual reproduction of flowering plants ?

(a) Zygote is converted into fruit

(b) Zygote is converted into seed

(c) Unicellular zygote is converted into multicellular embryo

(d) Ovary is converted into embryo

Answer

Question 1.6

Which structural part of a chromosome may occur either in the middle or at any one end of the Chromosome ?

(a) Telomere

(b) Nucleolar Organizer

(c) Satellite

(d) Centromere

Answer

Question 1.7

What are the dominant and recessive traits regarding the character related to the colour of flower of Pea plant ?

(a) Purple and Green

(b) Purple and White

(c) White and Purple

(d) Purple and Yellow

Answer

Question 1.8

What is the numerical ratio of the four genotypes BBRR, BBrr, bbRR and bbrr produced in the F2-generation resulting from dihybrid cross in Guinea pig ?

(a) 1 : 1 : 1 : 1

(b) 2 : 4 : 2 : 4

(c) 4 : 2 : 2 : 1

(d) 2 : 4 : 1 : 2

Answer

Question 1.9

If a female, looking apparently normal but being carrier of haemophilia, marries a normal male and if two sons and two daughters are born to them, then what would be the probability of manifestation of haemophilia among the children ?

(a) 100% haemophilic son and 0% haemophilic daughter

(b) 50% haemophilic son and 50% haemophilic daughter

(c) 0% haemophilic son and 50% haemophilic daughter

(d) 50% haemophilic son, and 50% apparently normal but carrier daughter

Answer

Question 1.10

Which of the following is a feature of Equus ?

(a) Three digits with hoof on each forelimb and hindlimb

(b) Four digits with hoof on each forelimb and two digits with hoof on each hindlimb

(c) Two digits with hoof on each forelimb and hindlimb

(d) One digit with hoof on each forelimb and hindlimb

Answer

Question 1.11

Which of the following is an inference of Darwin’s theory of evolution ?

(a) Natural Selection

(b) Variation

(c) Prodigality of reproduction

(d) Food and Space is constant

Answer

Question 1.12

What is the adaptive feature of Camel related to its ability to withstand extreme water loss ?

(a) Cylindrical Red Blood Corpuscle

(b) Circular Red Blood Corpuscle

(c) Oval Red Blood Corpuscle

(d) Cuboidal Red Blood Corpuscle

Answer

Question 1.13

With which step of Nitrogen Cycle microbes like Nitrosomonas and Nitrobacter are associated ?

(a) Nitrification

(b) Denitrification

(c) Nitrogen fixation

(d) Ammonification

Answer

Question 1.14

Which biological hotspots include Mizoram and Nicobar Islands respectively ?

(a) Eastern Himalayas, Western Ghats and Sri Lanka

(b) Sundaland, Indo-Burma

(c) Indo-Burma, Sundaland

(d) Sundaland, Eastern Himalayas

Answer

Question 1.15

Which types of in-situ conservation are Gorumara, Nilgiri and Kulik respectively?

(a) National Park, Biosphere Reserve, Sanctuary

(b) Biosphere Reserve, Sanctuary, National Park

(c) Sanctuary, National Park, Biosphere Reserve

(d) Biosphere Reserve, National Park, National Park

Answer

GROUP—B

2.  Answer 21 questions out of the 26 questions given below, as instructed. [1×21=21]

Question 2.1 – 2.6

Fill in the blanks with proper words in the following sentences (any five): [1×5=5]

The nucleated oval ____ cells occur between Medullary Sheath and Neurilemma of the axon of a neurone.

Spindle fibres and chromosomes are not formed in the ____ cell division.

Genetic Counselling helps to ascertain the presence of ____ gene of Thalassaemia disease.

The cause of biodiversity on earth is ____ .

Excessive amount of ____ is secreted from the walls of bronchi and bronchioles of trachea during Asthma.

If the detergent rich in ____ used for washing human clothes gets mixed in a pool, it results in eutrophication.

Answer

Question 2.7 – 2.12

Decide whether the following statements are True or False (any five): [1×5=5]

Accommodation is the ability of the retina of the eye to adjust the focal length as needed.

Mitotic cell division occurs while producing haploid spores.

The Guinea pig having the genotype BbRr is heterozygous for both the loci.

Vegetative organs indicate convergent evolution.

Liquid Nitrogen and-196℃ temperature are used in Cryopreservation.

Blind spot is the part of the eye devoid of light sensitive cells formed at the junction of optic nerve and retina.

Answer

Question 2.13 – 2.18

Match the words in Column A with the most appropriate words in Column B and rewrite the correct pair mentioning the serial no. of both columns (any five): [1×5=5]

Answer

Answer in a single word or in a single sentence (any six): [1×6=6]

Question 2.19

Choose the odd word and write it:

ADH, FSH, LH, TSH

Answer

Question 2.20

What is the name of the plant hormone breaking the dormancy of bud and seed ?

Answer

Question 2.21

On the basis of the relationship in the first related pair of words, write a suitable word in the gap of the second pair.

Purine : Adenine :: Pyrimidine : ____________  .

Answer

Question 2.22

What is the similarity between the two genes responsible for colour blindness and haemophilia ?

Answer

Question 2.23

What is the difference between the two genes responsible for the expression of attached ear lobes and roller tongue ?

Answer

Question 2.24

What is the role of salt gland present on the surface of the leaves of Sundari ?

Answer

Question 2.25

Among the following four terms, one includes the other three. Find it out and write it:

Coughing up thick phlegm, Bronchitis, Higher probability of smokers being affected, inflammation of the bronchi of Respiratory System of Man.

Answer

Question 2.26

Which aspect is the most emphasized in Project Crocodile’ launched for crocodile conservation ?

Answer

GROUP – C

3. Answer any 12 questions each in 2-3 sentences out of the 17 questions given below:- [2×12=24]

Question 3.1

What are the roles of Insulin hormone regarding the following two aspects related with metabolism of carbohydrates ?

• Breakdown of glucose
• Transformation of glucose

Answer

Question 3.2

Compare between Myopia and Hyperopia on the following two features:

• Cause
• Symptom

Answer

Question 3.3

One of the driving forces of locomotion is “Aggregation for the purpose of reproductive activities”—Establish the validity of the statement with the help of two marine animals.

Answer

Question 3.4

Which reflex actions does a spectator execute while watching a high voltage game on television ?

Answer

Question 3.5

Prepare a list of sites of occurrence of meiotic cell division in plants as well as in animals.

Answer

Question 3.6

Explain the alternation of generation in Fern with the help of a word diagram.

Answer

Question 3.7

How does the Cytokinesis of plant cell happen ?

Answer

Question 3.8

Explain the following two terms related with heredity —

• Allele
• Locus

Answer

Question 3.9

With the help of an example explain how the phenotypic and genotypic ratios found inF2 generation of certain hybrid crosses indicate exception to Mendel’s first law of heredity.

Answer

Question 3.10

What advantages did Mendel enjoy owing to pea-flowers being bisexual and self pollinating?

Answer

Question 3.11

What types of struggle for existence can be found among the animals of a forest over eating meat of a freshly killed prey ?

Answer

Question 3.12

How does a Rohu fish float and sink in water ?

Answer

Question 3.13

Prepare a list of reactants used and products in the experiment of Miller and Urey regarding biochemical origin of life.

Answer

Question 3.14

What environmental problems can originate if the concentration of different greenhouse gases polluting air increases in a steady manner ?

Answer

Question 3.15

Explain the causes of endangeredness of Polar Bear and Gangetic Dolphin.

Answer

Question 3.16

What might be the environmental causes behind asthma ?

Answer

Question 3.17

‘Scarcity of food and poaching are two main reasons behind the endangeredness of a mammal found in Eastern Himalayas biodiversity hotspot’ – Justify the validity of the statement.

Answer

GROUP – D

4. Write all the 6 questions or their alternatives given below. Visually handicapped candidates have to answer Question No. 4. 1 (A) instead of Question No. 4. 1. The marks allotted for each question are 5 (the division of marks is cither 3+2, 2+3 or 5). (5 × 6 = 30)

Question 4.1

Draw a scientific diagram of neuron and label the following parts: [3+2=5]

(a) Dendron

(b) Myelin Sheath

(c) Schwann Cell

(d) Node of Ranvier

Answer

OR

Draw a scientific diagram of eukaryotic chromosome and label the following parts: 3+2=5

(a) Centromere

(b) Satellite

(c) Nucleolar Organizer

(d) Telomere

Answer

(For Visually Handicapped Candidates Only)

Question 4.1 (A)

Write one function each of the following five parts of a neuron: [1×5=5]

(a) Dendron

(b) Axon

(c) Myelin Sheath

(d) Schwann Cell

(e) Node of Ranvier

Answer

OR

Write one function each of the following five parts of an eukaryotic chromosome: [1×5=5]

(a) Chromatid

(b) Centromere

(c) Nucleolar Organizer

(d) Satellite

(e) Telomere

Answer

Question 4.2

Write the name of the chemical constituents of eukaryotic chromosome with the help of a table. What happens to a cell when the cell loses control at different points in cell cycle on division ? 3+2=5

Answer

OR

What events occur during Anaphase stage of mitotic cell division ?Show the steps of sexual reproduction of flowering plants with the help of word diagram. 3+2=5

Answer

Question 4.3

With the help of a checkerboard show the phenotypic ratio of offsprings produced inF2 generation as a result of a cross between a pea plant having pure round yellow coloured seed and another pea plant having wrinkled green coloured seed. Write Mendel’s law of heredity derived from this experiment. [3+2=5]

Answer

OR

Demonstrate a cross for eradication of misconceptions prevailing among human society regarding the process of determination of sex among children. What are the symptoms of thalassaemia? [3+2=5]

Answer

Question 4.4

What information related to evolution can be obtained from the discussion on comparative structure of hearts of different vertebrate groups ?Explain the following two terms in the light of Darwinism – [3+2=5]

• Survival of the fittest
• Natural selection

Answer

OR

Explain the evolutionary significance of homologous and analogous organs with the help of example. What are the adaptive significances of air sacs of Pigeon ? 3+2=5

Answer

Question 4.5

Explain the following three problems related to ever-increasing human population-

• Over-exploitation and depletion of natural resourcese
• Changes in atmospheric condition and global warming
• Deforestation and loss of ecosystems

Two major causes behind the loss of biodiversity are over-exploitation and destruction of habitat due to change in land use pattern – establish the validity of the statement with proper example. [3+2=5]

Answer

OR

What might be the reasons behind the disturbances in Nitrogen Cycle ?It is very much essential to publish a PBR document for each village of India — which information can be gathered from a PBR regarding biodiversity ? 3+2=5

Answer

Question 4.6

One of the environmental problems of Sunderbans is imbalance in prey – predator number — Justify the validity of the statement with three examples. What are the roles of biosphere reserve and sanctuary in the conservation of biodiversity ? [3+2=5]

Answer

OR

What are the causes for the endangeredness of the following wild animals ? [3+2=5]

• Royal Bengal Tiger
• One-horned Rhinoceros
• Lion

What are the two effects of air pollution on human health ?

Answer

(For External Candidates Only)

GROUP – E

5. Answer any four questions: [1×4=4]

Question 5.1

Write one feature of connective tissue.

Answer

Question 5.2

What is the function of lysosome ?

Answer

Question 5.3

Write one function of collenchyma tissue.

Answer

Question 5.4

Write one disadvantage of cross pollination.

Answer

Question 5.5

Give one example of lipolytic enzyme.

Answer

6. Answer any three questions: [2×3=6]

Question 6.1

Write the names of the two structural parts of axon.

Answer

Question 6.2

Write the names of two non-nitrogenous excretory products of plants.

Answer

Question 6.3

Write one function each of cell wall and cell membrane.

Answer

Question 6.4

Write the names of two National Parks of West Bengal.

Answer