1. Complete The Sentence By Choosing The Correct Answer To Each Question And Writing Its Serial Number. 1 x 15 = 15

1.1 Select the correct pair —

(a) Cerebrum — Maintains body balance
(b) Hypothalamus — Controls intelligence and emotions
(c) Cerebellum — Controls body temperature
(d) Spinal cord — Controls heart rate and digestion

1.2 Identify which of the following statements regarding insulin is not correct:

(a) Helps in the absorption of glucose from the blood into most body cells
(b) Converts glucose into glycogen in the liver and muscle cells
(c) Helps in the conversion of fats and proteins into glucose
(d) Inhibits the conversion of proteins and fats into glucose

1.3 Match the words given in column ‘A’ with the words given in column ‘B’ and select which of the following answers is correct:

Pillar ‘A’ Pillar ‘B’

A. Flexion (i) Quadriceps
B. Extension (ii) Piriformis
C. Rotation (iii) Biceps

(क) A — (i) B — (ii) C — (iii)
(ख) A — (ii) B — (iii) C — (i)
(ग) A — (iii) B — (i) C — (ii)
(১) A — (ii) B — (i) C — (iii)

1.4 Select from the answers below at which stage of mitosis and karyokinesis of cell division the following two events occur:

(a) The two daughter chromosomes move away from each other towards their respective poles (b) The nucleolus and nucleolus disappear

(a) (a) Prophase
(b) (a) Anaphase (c) (a) Telophase
(c) Metaphase (
d) Metaphase (c) Telophase

1.5 Select which of the following is a characteristic of cross-pollination —

(a) Occurs within a flower of the same plant
(b) No vector is required
(c) The possibility of transmitting new traits is low
(d) Pollen wastage is high

1.6 Determine how many DNA molecules are coiled together in each chromosome of the newly formed daughter cell during mitosis in the human body.

(a) 46
(b) 1
(c) 23
(d) numerous

1.7 Identify the genotype of a guinea pig with black color and uneven fur—

(a) BbRr, BBRr
(b) BBrr, Bbrr
(c) bbRR, bbRr
(d) bbrr, bbRr

1.8 Determine which two of the following were selected by Mendel as latent traits —

(a) Flower colour — purple, flower position — axillary
(b) Stem length — short, mature seed shape — wrinkled
(c) Mature seed shape — round, seed colour — yellow
(d) Flower position — axillary, stem length — long

1.9 Determine from the following the possible genotypes of parents who have a hemophilic son and a normal daughter:

1.10 Parthenium is an exotic species in our country. Many native plant species cannot survive where it grows. This establishes a principle of Darwin’s theory. Identify the principle —

(a) Intraspecific struggle
(b) Interspecific struggle
(c) Struggle with the environment
(d) Origin of new species

1.11 Miller and Urey were able to synthesize some of the basic building blocks of life in their experiments. Identify which of them were amino acids —

(a) Lactic acid, acetic acid
(b) Urea, adenine
(c) Glycine, alanine
(d) Formic acid, acetic acid

1.12 Determine for which of the following purposes bees constantly swarm—

(a) Finding a breeding partner
(b) Informing other worker bees of the direction and distance of food sources from the hive
(c) Selecting a new hive site
(d) Avoiding attacks from potential enemies

1.13 Identify which of the following is the correct information regarding biosphere reserves —

(a) Conservation of the ecosystem is accompanied by conservation of local people and other living communities
(b) National parks and sanctuaries are not included in biosphere reserves
(c) Presence and participation of local people in conservation of the ecosystem is not allowed
(d) Its size is usually smaller than that of a sanctuary

1.14 Decide which of the following pairs is not correct —

(a) Poaching — Increasing gorilla endangerment
(b) Exotic species — Lantana, Tilapia
(c) Hotspot identification — Number of native species and endangered species
(d) Greenhouse gases — Eutrophication

1.15 Determine which of the following tiger projects is located in our state:

(a) Bandipur
(b) Simlipal
(c) Sundarbans
(d) Kanha

Category — ‘B’

2. Write the answers to 21 of the 26 questions below as instructed: 1 x 21 = 21

Fill in the blanks in the sentences below with the appropriate words (any five): 1 x 5 = 5

2.1 Acharya Jagadish Chandra Bose proved the ——

2.2 If gametes were produced by mitosis instead of meiosis in humans, the number of autosomes in a single cell of the offspring would be ___________.

2.3 A recessive genetic disease carried on the ‘X’ chromosome in the human population is __________.

2.4 The hoof of modern horses is a modification of the __________ toe of their ancestors.

2.5 In the __________ stage of the nitrogen cycle, ammonia is converted into nitrite and nitrate with the help of some bacteria.

2.6 A lot of __________ water is wasted in preparing the bottled cold drinks that are widely sold in the market.

Determine whether the following sentences are true or false (any five): 1 x 5 = 5

2.7 Tropic movement is the movement caused by plant growth.

2.8 Crossing-over occurs during mitosis.

2.9 Mendel used the word gene to describe his experiments on heredity.

2.10 Cactus leaves have been modified into spines to reduce the rate of transpiration.

2.11 Rhododendron is an endangered plant protected in the Eastern Himalayan hotspot.

2.12 The choroid helps the eye to accommodate by changing the curvature and shape of the lens:

Match the word given in column A with the most appropriate word given in column B and rewrite the correct pair (any five) mentioning the serial number of both columns: 1 x 5 = 5             

A-pillar B-pillar 

2.13 Gibberellins (a) rrYY
2.14 Branching (b) Groundwater renewal
2.15 Genotype of pea plants with shriveled and yellow seeds (c) Pyrimidine bases
2.16 Homologous organelles (d) Break the dormancy of buds and seeds
2.17 Wetlands (e) Same structure but different function
2.18 Thymine and uracil (f) RRYy
(g) Rose

Answer in one word or one sentence (any six) 1 x 6 = 6

2.19 Choose the opposite word and write it: brainstem, hypothalamus, pons, thalamus

2.20 Where is the swan’s nest?

2.21 A pair of related words is given below. Understand the relationship between the first pair and fill in the blanks in the second pair with the appropriate word.

Mitosis : Embryo : : Meiosis : __________

2.22 What conclusion did Mendel arrive at from his bihybrid breeding experiment?

2.23 Give an example of a genetically transmitted variant that is seen in healthy people.

2.24 How do chimpanzees break open hard shells and eat nuts?

2.25 Out of the four topics below, three belong to one topic. Find out and write that topic: SPM, Air pollution, Greenhouse gas, Lung disease

2.26 Write the name of the system followed by local people and the forest department jointly for forest restoration.

Category — ‘C’

3. Write the answer to any 12 of the 17 questions below in two or three sentences. 2 x 12 = 24

3.1 Identify the differences between the work of hormones and the nervous system in the following areas: (a) Nature of work (b) Speed ​​of work (c) Durability of work (d) Consequences

3.2 A person can see distant objects clearly but cannot see close objects well — guess what the causes and remedies for such a problem might be.

3.3 Analyze the role of synthetic plant hormones in increasing agricultural yields and solving weed problems.

3.4 ‘LH and ICSH control the secretion of hormones from the gonads in the human body’ – judge the correctness of the statement.

3.5 How would you determine the difference between mitosis in plant and animal cells based on these two features: cell division and cytokinesis process?

3.6 Establish the relationship between loss of control in the cell cycle and the formation of malignant tumors in the human body.

3.7 ‘Alien leaf buds play a significant role in the natural vegetative propagation of plants’ — Evaluate the correctness of the statement with the help of a suitable example.

3.8 Show by means of a cross which of the father and mother is more important in determining the sex of the child.

3.9 ‘Different genotypes produce the same phenotype’ – Prove the correctness of the statement with the help of a table, taking an example of the results of the pea plant dihybrid breeding experiment.

3.10 Share your opinion on what advice can be given to prospective couples before marriage to prevent the spread of a genetic disease that you know about from society.

3.11 A number of tilapia fish have been released into a pond that naturally contains only various native species of fish. Describe the struggles that these tilapias must face to survive.

3.12 Make a list of the roles played by the air sacs of pigeons for flying in the air.

3.13 (a) Structure and function (b) Type of evolution Based on the above two characteristics, establish the concept of symmetrical organs with suitable examples.

3.14 Relate the following phenomena to the disruption of the nitrogen cycle due to various human activities — (a) Global warming (b) Acidification of soil and water in rivers and lakes

3.15 Hilsa, bee, penguin, snakehead – determine what could be the reasons for the endangerment of the above creatures.

3.16 Discuss any two roles of the People’s Biodiversity Registrar (PBR) in conserving local biodiversity.

3.17 List any four activities that are prohibited in sanctuaries as per the Wildlife Act.

Category — ‘D’

4. Answer the following 6 questions or their alternative questions. Visually impaired candidates should answer question 4.1 (A) instead of question 4.1. 5 x 6 = 30

4.1 Draw a neat diagram of the cross-section of the human eyeball and identify the following parts: 3 + 2 = 5

(a) Choroid (b) Optic nerve (c) Iris (d) Macula

Or

Draw a neat diagram of the metaphase stage of mitosis cell division of an animal cell and identify the following parts: 3 + 2 = 5

(a) Chromatid (b) Centromere (c) Polar region (d) Unpaired

(For visually impaired candidates only)

4.1 (A) Write one function of each of the following parts of the human eyeball: 1 x 5 = 5

(a) Vitreous humor (b) Sclera (c) Iris (d) Lens (e) Retina

Or

Write three characteristics of the metaphase stage and two characteristics of the anaphase stage of mitosis in animal cells. 3+2=5

4.2 Distinguish between mitosis and meiosis cell division in animals based on the following characteristics: (a) Place of execution (b) Nature of chromosome division (c) Number of cells produced

List the changes in the senses and bones that occur during the aging stage of human development. 3+2=5

Or

Explain the importance of the following parts of a eukaryotic chromosome: (a) Centromere (b) Telomere

Analyze how the growth, reproduction, and repair of organisms are controlled by cell division. 2+3=5

4.3 Write the three pairs of apparent-recessive traits of pea plants selected by Mendel with the help of a table. State Mendel’s first law obtained from the one-hybrid breeding experiment. 3+2=5

Or

A color blind woman married a normal man. Estimate the probability of color blindness among their children in the first generation. In the case of evening primrose, show how the deviation of Mendel’s first law of inheritance is manifested in the F2 generation by means of a cross. 3+2=5

4.4 Show the main events of biological expression after the origin of life in order with the help of arrows.

Or

Discuss the following three aspects of Darwin’s theory of evolution: (a) Rapid evolution (b) Origin of variation (c) Natural selection

‘Adaptation is a change in the size, physiological functions and behavior of an organism’ —Prove the correctness of the statement with any two examples. 3+2=5

4.5 Evaluate the impact of the following pollutants on the environment and human health: 5

(a) Inert pesticides
(b) Pollen
(c) Chemical fertilizers rich in phosphates and nitrates
(d) Germ-rich waste from health centers
(e) Chlorofluorocarbons

Or

Guess what the possible causes of each of the following events could be: 5

(a) Insomnia, increased blood pressure, partial or complete deafness
(b) Decrease in dissolved oxygen levels in water and dead fish floating around
(c) Decrease in crocodile numbers
(d) Inflammation of the airways of the lungs
(e) Decrease in the number of insects that help in pollination

4.6 ‘The increasing population in various cities of India has created a groundwater crisis’ – Support the statement with arguments based on your experience. Create a concept map of how the increase in human settlement is affecting the ecosystem of the Sundarbans. 3+2=5

Or

Write a summary of the conservation efforts undertaken to increase the population of an endangered mammal found only in the wetland grasslands of the eastern Himalayan foothills. Discuss the importance of biodiversity in maintaining the balance of river ecosystems. 3+2=5

Category — ‘E’

(For external candidates only)

5. Answer any 4 questions: 1 x 4 = 4

5.1 Write one characteristic of the endosperm.
5.2 Which cell organelle is called “suicide sac”?
5.3 Write one function of the parenchyma.
5.4 Give an example of an insect-pollinated flower.
5.5 Give an example of a protein-digesting enzyme.

6. Answer any 3 questions: 2 x 3 = 6

6.1 Write two differences between axon and dendron.
6.2 Write the names of two excretory systems of plants.
6.3 Write one function each of mitochondria and plastids.
6.4 Write the names of a national park and a biosphere reserve of West Bengal.