Madhyamik life science Question Paper 2019 Solve

WB Madhyamik life science Solve

Madhyamik Pariksha 2019 Solve- life science

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SUBJECT: life science Year: 2019

Group A

Complete the sentence by choosing the correct answer and answer by mentioning their serial number:

1.1 Select which of the following statement is correct related to tropic movement-

(a) It is controlled by the intensity of the stimulus

(b) Overall change of place takes place by a plant or part of the plant

(c) This movement is observed in the algae called Volvox

(d) It is an induced movement of curvature controlled by the direction of the stimulus

Ans. (d) It is an induced movement of curvature controlled by the direction of the stimulus

1.2 Read the following sentences and identify the sentence which is not correct-

(a) FSH, LH, and Prolactin are different types. of GTH

(b) Adrenaline decreases cardiac output

(c) [Insulin facilitates the absorption of glucose into the cell through the cell membrane.

(d) Progesterone helps in the formation of the placenta the in female body

Ans. (a) FSH, LH, and Prolactin are different types of GTH

1.3 Determine the number of Cranial nerves in the human body

(a) 10 Pairs (b) 31 Pairs (c) 12 Pairs (d) 21 Pairs

Ans. (c) 12 Pairs

1.4 Identify the correct feature of Amitosis cell division-)

(a) Occurs in germ mother cell of sexually reproducing organism

(b) It is called indirect cell division

(c) Chromosome and Spindle fiber are formed

(d) Chromosome and Spindle fiber are not formed

Ans. (d) Chromosome and Spindle fiber are not formed

1.5 Determine which of the following statement is correct regarding the significance of meiosis-

(a) It results in overall growth and development of the body

(b) It results in the growth of reproductive organs and embryos of the organism.

(c) It produces haploid gametes containing hereditary variations.

(d) It regenerates the organ in the body of some animals if it is lost.

Ans. (c) It produces haploid gametes containing hereditary variations.

1.6 Select the correct pair and write it –

(a) Multiple fission Hydra

(b) Fragmentation Spirogyra

(c) regeneration-Fern

(d) Budding—Planaria

Ans. (b) Fragmentation—Spirogyra

1.7 Identify which of the following is a dominant trait-

(a) Length of the stem Dwarf

(b) Shape of the seed – Wrinkled

(c) Colour of the cotyledon Yellow

(d) Colour of the flower-White

Ans. (c) Colour of the cotyledon Yellow

1.8 Assess how many types of gametes are produced from the Pea plant having the genotype RRYY-

(a) One type (b) Four types

(o) Two types (d) Three types

Ans. (c) Two types

1.9 Select which of the following two genotypes are responsible for the expression of the phenotype wrinkled yellow in Pea plant-

(a) RRYY rryy

(b) RRYy RrYy

(c) RRyy Rryy

(d) mYY Yy

Ans. (c) RRyy Rryy

1.10 Identify which of the following indicates interspecific struggle-

(a) Struggle among the members of guppy fish for feeding on mosquito larvae

(b) Struggle between snakes and owls to capturing rats for eating

(c) Struggle within a group of deer for feeding on grass at the same location

(d) Struggle between tigers in a jungle for preying on deer

Ans. (b) Struggle between snakes and owls for capturing rats for eating

1.11 Determine the term related to the theory of Lamarck-

(a) Struggle for existence

(b) Origin of variation

(c) Inheritance of acquired characters

(d) Natural selection

Ans. (c) Inheritance of acquired characters

1.12 Identify the animal that communicates information with other members of its group through specific dancing patterns regarding the sources of food-

(a) Chimpanzee

(c) Peacock

(b) Cockroach

(d) Honeybee

Ans. (d) Honeybee

1.13 Decide which of the following if remains for a long time in the environment, the – probability of its biomagnification increases-

(a) Newspaper

(b) Faecal matters of animals

(c) Rotten leaves

(d) Chlorinated insecticide

Ans. (d) Chlorinated insecticide

1.14 Gorumara, Corbett, Kulik, Nandadevi-choose the correct sequence from the following which is correct for the above forests in sequence-

(a) Biosphere Reserve, Sanctuary, National Park

(b) National Park, National Park, Biosphere Reserve, Sanctuary

(c) National Park, National Park, Sanctuary, Biosphere Reserve

(d) Sanctuary, Biosphere Reserve, National Park, Sanctuary

Ans. (b) National Park, National Park, Biosphere Reserve, Sanctuary

1.15 If the number of pollen grains, fungal spores, and dust particles increases suddenly in the air, decide which of the following problems may increase

(a) Tuberculosis (b) Asthma (c) Malaria (d) Dengue

Ans. (b) Asthma

Group ‘B’

Answer any 21 questions out of 26 questions given below as instructed.

Fill in the blanks with proper words in the following sentences (any five):

2.1 By the influence of ______ hormone the hairs on the skin get erected in an emergency situation.

Ans. Adrenaline.

2.2 Chromosome is the condensed coiled structure of _______molecule.

Ans. D. N.A.

2.3 The sexual reproduction that occurs among two genotypically different organisms belonging to the same species, is called _______.

Ans. Hybridization.

2.4 was the aggregate of some large colloidal molecules during the early phase of origin _______ of life.

Ans. Conserve

2.5 ________ is derived from the root of the Sarpagandha plant which is used as medicine for lowering high blood pressure.)

Ans. Reserpine.

2.6 The ex-situ conservation by keeping sample seeds in liquid nitrogen at a temperature of-196°C is called-

Ans. cryopreservation

Decide whether the following statements are true or false (any five):

2.7 Dilute urine is profusely eliminated by a person affected with Diabetes Insipidus.

Ans. T

2.8 The Carpel of flowering plants collects pollen grains with the help of a hairy and sticky style.

Ans. F

2.9 A pair of sex-determining sex chromosomes are present in the ovum of humans.

Ans. F

2.10 According to Darwin organisms reproduce at geometric ratios.

Ans. T

2.11 One-horned rhinoceros is conserved at Manas National Park of West Bengal.

Ans. T

2.12 Acetylcholine and adrenaline are neurotransmitters.

Ans. F

Match the words in Column – A with those which are most appropriate in Column B and re-write the correct pair mentioning the serial no. of both columns (any five):

Column – A	Column – B
2.13 Presbyopia	(a) BbRr
2.14 Cell Differentiation Phase of Growth	(b) Haldane
2.15 Genotype of Guinea -pig having black and coarse hair	(c) Near vision is defective
2.16 Hot Dilute Soup	(d) Change of climate and global warming
2.17 Destruction of forest and erosion of ecosystem	(e) Formation of spindle fiber during animal cell division
2.18 Centrosome	(f) Formation of tissue, organ, and system
	(g) bbrr

Ans. 2.13 – (c), 2.14 – (f), 2.15 – (a), 2.16 – (b), 2.17 – (d), 2.18 – (e)

Answer in a single word or a single sentence (any six):

2.19 Choose the odd one and write it: Glossopharyngeal, Oculomotor, Trigeminal, Oxytocin

Ans. Oxytocin

2.20 What is the function of the fluid present in the intermediate chamber between the lens and retina of the eyeball?

Ans. Shape / Fixed shape.

2.21 A pair of related terms is given below. Based on the relationship in the first pair write the suitable word in the gap of the second pair. Grafting: Mango :: China Rose : ____

Ans. pen

2.22 What is the cause of expression of hemophilia disease only at homozygous conditions?

Ans. In the homozygous stage, only one chromosome of the carrier has the genes for (x) hemophilia.

2.23 Write the genotypic ratio obtained at 2nd filial generation in the monohybrid experiment done by Mendel.

Ans. 1:2:1

2.24 Which type of evolution is indicated by homologous organs?

Ans. Terrestrial animals have evolved from aquatic animals.

2.25 Among the following four terms one includes the other three. Find it out and write it: Pesticides used in Agriculture, Typhoid, Water Pollution, liquid wastes from factories.

Ans. Typhoid

2.26 In which type of in situ conservation practice, the diversity, culture, and lifestyle of humans are preserved along with microorganisms, wild animals, and wild plants?

Ans. By Public Biodiversity Account (PBR) (National Parks / Sanctuaries / Protected Forests and Biosphere Reserves and

Group C

Answer any 12 questions in 2-3 sentences out of the 17 questions given below 🙂

3.1 Illustrate with the help of a word diagram the nervous pathway of the way you will open the door by hearing the doorbell.

Ans.

3.2 State the locations of Meninges and CSE.

Ans. Ministries and CSF are located around the brain and spinal cord and in the central canal of the spinal cord.

3.3 What influences does the gibberellin hormone exert on the seeds and internode of plants? Explain.

Ans. The gibberellin hormone removes genetic dwarfism. Increases the length of the festival. An increase in Parva Sandhi Increases the length of the festival.

3.4 Write the names of the different refractive mediums of the eyeball in proper sequence.

Ans. Conjunctiva cornea (luminous) A.H – lens – (spheroid) V.H.

3.5 During the meiosis cell division, reduction in the number of chromosomes and exchange of segments between chromatids take place-Analyze what the significances of these two phenomena are.

Ans. In meiosis cell division, the main reason for the reduction in the number of chromosomes is the gamete (Egg, Sperm) because the number of chromosomes in the gamete is half the number in the mother cell. In meiosis, crossing over occurs due to the exchange of segments in the middle of the chromatids, allowing organisms to exchange opportunities, resulting in genetic variation.

3.6 Distinguish between asexual and sexual reproduction based on folio wing features:

Ans.

Asexual reproduction

sexual reproduction

number of parents

nature of offspring

Only one parent takes part in this reproduction.

Organisms produced in this reproduction are identical to the parent and variations do not arise.

Male and female parents participate in this reproduction.

The organism produced in this reproduction includes the qualities of both parents, as a result, variations arise.

3.7 Identify the stages of Karyokinesis of mitotic cell division depending on the following features:

Alignment of chromosomes along the cell’s equator and their arrangement in a definite pattern.

Ans. Metaphase.

Disintegration of spindle fibers
Ans. Anaphase.

Disappearance of nuclear membrane and nucleolus.

Ans. At the end of the prophase.

Movement of daughter chromosomes to the opposite poles of the cell.

Ans. Telophase.

3.8 To establish the law of segregation in the case of Pea plants, you are asked to select characters. Write two such characters having opposite traits.

Ans. Length. tall and short

color red and white black and white

3.9 A daughter is born to a woman carrier for the colorblind disease who married a color-blind man. What would be the probability of expression of color blindness in that girl child? Analyze your answer.

Ans. Generation-to-generation transmission of color blindness with the help of cross: Father’s sex chromosome – XY, mother’s sex chromosome – XX (It is the carrier of color blindness.)

FEMALE GAMETES

MALE GAMETES

X⁰

X⁰X

DAUGHTER

X⁰Y

SON

DAUGHTER

SON

3.10 Write the name of two genetic diseases which are expressed in human populations.

Ans. Hemophilia, color blindness.

3.11 Tigers are extinct but there are many deer in the jungle. A few tigers are brought from another sanctuary and released in such a jungle. Imagine and write the names of those tigers that have to be involved in different kinds of struggles for existence.

Ans. Inter-caste, inter-caste, and environmental conflicts will have to be faced.

3.12 Describe any two adaptations in the Sundari plant for tolerance of salt.

Ans. Description of suitable adaptations in succulent plants for tolerance to salts:

(1) The roots of the Sundari plant (Musla root) penetrate deeper where the salt concentration is reduced and many fibrous roots and respiratory roots (pneumatophores) As a result, the root cells can absorb salt-free water by the method of osmosis, in a lesser amount from a greater area (area).

(2) Leaves are thick, fleshy, with smooth cuticle covers, which have more ability to store water and have glands to store salt, when the leaves break, the salt comes out of the body in the form of excretory material.

3.13 Mention two behavioral adaptations for problem-solving in chimpanzees.

Or, Explain how the chimpanzees hunt termites for food.

Ans. Behavioral adaptations for problem-solving in chimpanzees: –

(i) Chimpanzees break and eat coconut using wooden pieces as hammers and anvils.

(ii) By breaking a thin branch of a tree, removing its leaves, making a stick, and putting it in the burrow of termites eat it by removing termites.

3.14 List the harmful effects of the following pollutants:

Greenhouse gas:

Ans. The harmful effect of Green House Gas – Global Warming.

SPM:

Ans. Asthma, cancer.

Chemical fertilizers used in agriculture

Ans. Soil acidity.

Non-biodegradable chemical insecticide

Ans. D. D. T.

3.15 Give one example of exotic species causing damage to local biodiversities in each terrestrial and aquatic ecosystem.

Ans. terrestrial

(i) Python (European gypsy math), (ii) Rabbit (European starting)

Aquatic bird :

(i) Snail (Zebra Muscle) (ii) Hydrilla (Chinese Mittuch crab) Crab

3.16 Write the in situ conservation measures taken for one endangered reptile species and name one site of such conservation in West Bengal.

Ans. “Sundarvan” (Bhagwat Pur Crocodile Project)

3.17 “Poaching is one of the fundamental causes of endangered Ness of animal diversity in India”-Assess four causes for which animals are poached in India.

Ans. For (i) meat (ii) leather (iii) rhinoceros horn (iv) ivory, etc.

Group D

Answer six questions or their alternatives given below. Sightless candidates have to answer question

4.1 Draw a neat diagram of a neuron and label the following parts:

(a) Dendron (b) Node of Ranvier (c) Myelin sheath (d) Schwann cell

Draw a neat diagram of the anaphase of mitosis of an animal cell and label the following parts : (a) Polar region (b) Spindle fiber (c) Chromatid (d) Centromere

4.1 (A) Write one function of each of the following five parts of a neuron:

(a) Dendron (b) Cell body (c) Axon (d) Myelin sheath (e) Schwann Cell

mention three changes that occur in the anaphase stage of mitosis in animal cells. Write the name of any two structural parts of the eukaryotic chromosome.

4.2 Why reproduction is important for an organism? “Meiosis is characteristically different from Mitosis” – how would you justify the statement?

Describe five processes of asexual reproduction with one suitable example for each.

4.3 Show the result of hybridization till F₂ generation between a pure black (BB) coarse-haired (RR) guinea pig and a pure white (bb) smooth-haired (rr) guinea pig by a checkerboard. State the conclusion one can reach from this hybridization experiment.

4.5 “Luxurious and comfortable lifestyle is one of the major reasons for air pollution”–Support the statement with arguments.

4.6 “Change of climate and global warming is a problem resulting from the increasing human population”-Summarize what impacts it might exert on the environment. “Children and adults both suffer from different respiratory problems during the winter”- Write two names of such problems and state one symptom of each of them.

You have identified three environmental problems while on research in Sunderbans-

Disbalance in prey-predator number)
Destruction of mangrove plants due to urbanization)
Submergence of islands due to rising sea levels

Analyze what impacts they might exert on biodiversity. Write the location of the Sundaland hotspot and one important species of its biodiversity.