Question 1

Question 1Describe the structure of a neuron with the help of a diagram.

Accepted Answer

A neuron is the longest cell of our body. It has three parts — cell body, axon and dendrites.The cell body called cyton contains the nucleus.Many short fibres called dendrons arise from the cell. They further divide to form dendrites. Dendrites receive messages from other neurons.A single, long fibre called axon extends from the other side of the cell body. It is covered by a sheath called myelin sheath.Below diagram shows the structure of a neuron:

Question 2

Question 3Describe the various physical changes that occur during adolescence.

Accepted Answer

The various physical changes that occur during adolescence are:Sexual maturation — In males testes start producing testosterone and sperms. In females, the ovaries start releasing eggs and produce the female hormones, oestrogen and progesterone. Sex organs develop fully and secondary sexual characteristics like enlargement of external genital organs in males and enlargement of breasts in females also start.Increase in height — There is a spurt in growth hormone leading to sudden increase in height due to the elongation of the bones of the legs and arms. Age by which full height is attained is 14 to 15 years for girls and 18 to 19 years for boys.Change in body appearance — In males, the shoulders become broad and the chest becomes wide.The muscles also grow and develop more than in girls. In females, there is widening of the pelvic region and broadening of the hips. The breasts also develop and enlarge in size. Also in both males and females, hair starts growing in the armpit and pubic area. In males, facial hair (as beard and mustache) grows.Change in voice — There is growth in the voice box or larynx. It grows more in males than in females. As a result, males develop deep voice whereas females develop a high-pitched voice.

Question 3

Question 5List five ways in which fungi help mankind.

Accepted Answer

Five ways in which fungi help us are:They decompose the dead, decaying bodies of plants and animals. Fungi also helps in making the soil fertile.Morels and some mushrooms are consumed as delicacies.Yeast is used in baking industry.Alcohol and alcoholic drinks are produced by the fermentation of grapes, barley etc. by yeast.Yeast is also used for manufacturing vitamins. Penicillin, an antibiotic, is obtained from Penicillium, a fungi.

Question 4

Question 2endocrine and exocrine glands

Accepted Answer

Sl.No.Endocrine glandsExocrine glands1.Endocrine glands are specialized glands which release their secretions directly into cells or the surrounding tissue.Exocrine glands are glands which release their secretions through ducts to the target organ.2.Endocrine glands are ductless glands.Exocrine glands are glands with ducts.3.Endocrine glands secrete hormones.Exocrine glands secrete enzymes.4.Response time is slower since the secretion has to be carried through blood.Response time is fast since the secretion is carried through ducts.5.They control long term activities of the target organ.They control short term activity.6.Examples are: Pituitary gland and thyroid glandExamples are: Salivary glands and sweat glands

Question 5

Question 4vaccination and immunization

Accepted Answer

Sl.No.VaccinationImmunization1.Administration of a weakened or inactive pathogen (a vaccine) to stimulate the immune system to develop resistance against that pathogen is called vaccination. A vaccine can be injected or taken orally.The process by which a person is made resistant or immune against a particular disease by administering a vaccine is called immunization.2.It is the process of administering vaccine. A vaccine may not always guarantee immunity.It is the process of making a person immune to a particular disease.

Question 6

Question 6sericulture and apiculture

Accepted Answer

Sl.No.SericultureApiculture1.The breeding and management of silk worm for the production of silk is called sericulture.The breeding and management of honeybees for commercial purpose is called apiculture.2.It is done for Silk.It is done for Honey and Beeswax.

Question 7

Question 7The breeding and management of silkworms for the production of silk is called ............... .

Accepted Answer

The breeding and management of silkworms for the production of silk is called sericulture.

Test Paper 2

Answer the following in detail.

Differentiate between

Fill in the blanks