CLASS - VIII

[BIOLOGY]

➢ SYLLABUS FOR FIRST TERM EXAMINATION:

Ch – 1 (Transport in Plants) Ch – 2 (Reproduction in plants),

Ch – 3 (Reproduction in humans) Ch – 4 (Eco-systems)

➢ HALF YEARLY PROJECT WORK:

Students you all have to prepare a booklet using chart paper (of any

colour) for drawing any six diagrams from the following given below. Also

you all have to give the proper heading, proper labelling and proper

colouring for the diagrams you are drawing. Topics are as follows:

1. Female reproductive system

2. A nerve cell

3. Double circulation

4. Internal structure of heart

5. Reflex action and reflex arc

6. Adrenal gland and thyroid gland

7. A typical flower

NOTE: All the diagrams are in your respective books. You all can take the

help of internet as well. Your project should be well decorated and should

be neat and clean. Do not use much bright decorations. Try to keep it

simple and creative,

➢ STUDY MATERIAL : CH – 1 [ TRANSPORT IN PLANTS]

1. Conducting system – Transport of water and food in plants is carried

out by two main tissues: Xylem and Phloem. Together they are also

called vascular bundle.

2. Xylem: it mainly transports water and mineral salts from the roots

to the aerial parts of the plant. Hence, its conduction is

unidirectional, Parts of xylem are- Tracheids, Vessels, Xylem

parenchyma and Xylem fibres. They give strength and support to the

plants.

3. Phloem : it mainly transports the food from the leaves to all parts of

the plants. Hence its conduction is bidirectional. Parts of phloem are

sieve tubes, companion cells, phloem parenchyma and phloem fibres.

4. Transpiration: the loss of water due to evaporation from the aerial

parts of the plants is called transpiration. The factors affecting

transpiration are: sunlight ( more sunlight more transpiration),

humidity (more humidity less transpiration), wind(more wind more

transpiration) temperature (more temperature more

transpiration).

5. Osmosis: the movement of the molecules from their higher

concentration to lower concentration with the help of a semi

permeable membrane is called osmosis.

6. Diffusion: the movement of the molecules from their higher

concentration to lower concentration without the help of a semi

permeable membrane is called diffusion.

Some more points to understand:

1. Transpiration helps the plants to cool down and also to maintain

the concentration of sap (plant cell fluid)inside the plant body.

2. Water in the plants helps in transpiration, food production and

giving a cooling effect to the plants.

3. Semi- permeable membrane means a type of thin membrane

which allows only the small particles to enter and does not allows

the entry of large particles in a solution. Whereas, freely

permeable membrane is a type of thin membrane which allows all

the particles to pass through may be it is small or large. Cell wall

is an example of freely permeable membrane whereas cell

membrane is an example of semi- permeable membrane.

4. Difference between xylem and phloem is very important.

QUESTIONS TO BE SOLVED OUT:

1. What is the function of xylem and phloem?

2. What is the difference between xylem and phloem?

3. What do you mean by vascular bundle?

4. Name the parts of xylem?

5. What is the difference between diffusion and osmosis?

6. Name the factors affecting transpiration and how?

7. What do you mean by semi permeable membrane and fully

permeable membrane?

8. What is conducting system?

9. Give one example of semi permeable membrane and one freely

permeable membrane. Define transpiration.

STUDY MATERIAL: CH – 2 [REPRODUCTION IN PLANTS]

1. Reproduction: the process of producing young ones of the same kind

is called reproduction. Mainly reproduction is of two types: sexual

reproduction and asexual reproduction.

2. Sexual reproduction: where two parents are involved and there is a

fusion of male and female gametes (sex cells). Ex- human beings,

mammals.

3. Asexual reproduction: where only one parent is involved and there is

no fusion of gamete cells. Ex- plants, bacteria.

4. Types of asexual reproduction:

• Binary fission- splitting into two identical small cells like

bacteria. Organisms like Clorella and Chlamydomonas split

into four daughter cells. Hence called multiple fission.

• Budding – the parent cell grows as an outgrowth or bud and

gets detached when matured. Ex – Yeast.

• Fragmentation – reproduction takes place when ribbon like

filaments break into two parts and grow as an individual

organism. Ex – Spirogyra.

• Spore formation – the light weight spores grown in the plants

can be carried away with the help of wind and they re-grow

when they get suitable conditions to germinate. Ex – mosses,

ferns.

• Vegetative propagation – when the new plant is grown with

the help of any part of a plant like stem, root and leaf. It is of

two types:

a) Natural vegetative propagation : it includes

reproduction by stem(ginger, potato,

onion),reproduction by leaf (bryophyllum) and

reproduction by root (sweet potato).

b) Artificial vegetative propagation : it includes *

Cutting (stem is cut into small pieces and planted into

moist soil to re-grow into an individual plant . Ex –

Rose, Lemon, Sugarcane.) * Layering (one of the

lower branch of the plant is bent and buried into the

soil and the new plant is grown from the other end. Ex

– Jasmine, Mint) * Grafting (one part of the plant is cut

and tied with other part of the plant. Ex – guava) *

Micro- propagation (when the tissue of any plant is

being used for reproduction.)

NOTE: Artificial part will be explained in details after the school re-opens.

5. Sexual reproduction: in case of plants flower is a reproductive part

which bears male and female parts as well as on fusion of both the

gametes seeds are produced as a result of fertilization.

6. Parts of flower: a typical flower is made up of mainly four parts.

They are *Calyx(sepals)-they are green and help in photosynthesis.

*Corolla(petals)- they are the colourful part of the flower and

attracts insect for pollination *Androecium(stamens)- it is the male

part of flower made up of long, narrow and thin filament and a bi-

lobed sac called anther mainly carries pollen grains and

*Gynoecium(pistil)- it is the female part of a flower made up of

ovary, style, and stigma.

7. Types of Flowers : flowers having both male and female parts are

called bisexual flower whereas flowers having only one (male or

female) part are called unisexual flowers.

8. Pollination: the process of transfer of pollen grains from anther to

the stigma is called pollination. Pollination is of two types:* Self

pollination(no agent required) and * Cross pollination (agents like

insects, wind and water).

9. Fertilization in plants : fusion of the male and female sex cells in

plants is called fertilization in plants.

10. Self pollination means the pollination that takes place within the

same flower of the same plant.

11. Cross pollination means the pollination that takes place within the

different flower of the different plants.

NOTE: Agents of cross pollination and their characteristics will be

explained in details after the school re-opens.

QUESTIONS TO BE SOLVED OUT:

1. What is fertilization?

2. Name the parts of a typical complete flower.

3. What are the types of natural vegetative propagation? Give one

example of budding and fragmentation.

4. What is the difference between sexual and asexual reproduction?

5. What is pollination? Name its types.

6. What is the difference between self pollination and cross pollination.

7. What is layering? Give one example.

8. What is reproduction?

9. What are gametes?

10. Name the part of a plant where anther is present? Is it a male or a

female part?

11. What is the difference between binary fission and multiple fission?

12. Which part of a flower is also called petals? Give the function of the

part.

13. Which part of the flower is responsible for photosynthesis?

➢ STUDY MATERIAL: CH – 3 [REPRODUCTION IN HUMANS]

1. Gametes: these are also called sex cells. The male sex cells are called

sperms and the female sex cells are called eggs. The fusion of sperm

and egg forms zygote which develops into a baby.

2. Reproduction: in animals reproduction can be sexual and asexual

reproduction.

3. Asexual reproduction in animals: it mainly consists of *Fission

(Binary and multiple) - mainly can be seen in amoeba, paramecium.

* Budding - mainly can be seen in hydra.* Regeneration - it can be

mainly seen in hydra, starfish and planaria.

4. Sexual reproduction in animals: it mainly is made up of male

reproductive system and female reproductive system.

5. Male reproductive system: it is an important part. The main parts

are : * Scrotum- helps in maintaining the suitable

temperature of sperms.

* Pair of testis – sperms are produced here and matured.

*Epididymis – it is a part of testis where the sperms are

formed by the process of spermatogenesis.

*Sperm duct: it helps in transfer of sperms.

*Penis- the urine and sperms are released by this

pathway for boys

*Glands- there are three glands in total .they are prostate

gland(pours alkaline solution), cowper’s gland(serves as

lubricant) and seminal vesicles(medium of transport).

6. Semen: it is mainly the mixture of sperm and the secretions of the gland

whereas sperm is the fluid without the secretions of gland.

7. Female reproductive system: it mainly is made up of –

*Pair of ovary- eggs are produced here.

*Uterus – it is a part where implantation takes place.

*Oviduct/Fallopian tube- fertilization takes place here.

*Vagina – where the uterus opens.

8. Fertilization: the fusion of the male and female gametes forms zygote.

9. Implantation: the fixing of embryo in the wall of uterus.

10. Gestation/Birth: it includes 280 days. The complete development of the

embryo in the uterus is called gestation.

11. Embryo: the stage of the development of the zygote after cell division is

called embryo.

QUESTIONS TO BE SOLVED OUT:

1. What is the function of testis and ovaries?

2. What is the difference between sperm and semen?

3. Define the term fertilization and gestation

4. What do you mean by lubricant?

5. Name the glands present in male reproductive system

6. In which animals we can see regeneration?

7. Where are the sperms and eggs produced?

8. What is the function of scrotum?

9. What is the difference between zygote and embryo?

10. Is implantation and fertilization same?

➢ STUDY MATERIAL: CH – 4 [ECO-SYSTEMS]

1. Eco system: a composed area where different organism are directly

or indirectly depended on each other.

2. Components of eco system: biotic and abiotic

3. Biotic components: it mainly includes the various animals as per

their tropic levels, who are also called producers (who produce food)

and consumers (who consume food). They also include the following:

*Scavengers: like vultures, crows, kites

*Detritivores: earthworm, slugs

*Decomposers: bacteria, fungi.

4. Abiotic components: it mainly includes the physical conditions like

sunlight, temperature, water, temperature, soil and air.

5. Food chain: the process where the animals from lower number to

higher number is arranged according to their consumption.

a. Ex: grass→grasshopper→frog→snake→eagle.

b. Ex: plant→rat→owl

c. Ex: grass→rabbit→stoat

6. Food web: a network of several food chains is called food web.

7. Symbiosis: a relationship where both the organisms are in benefit.

Ex: animals help in pollination and plants help by giving food

8. Parasitism: a relationship where only one organism is in benefit

whereas the other organism is in loss. Ex: host and parasite where

host is in loss and parasite is benefitted.

9. Predation: a relationship where one organism is dominated by the

other. Ex: tiger and deer where tiger is domination the deer.

10. Flora and fauna: rhinoceros (jaldapara sanctuary), tiger(Jim

Corbett national park) lion(gir forest).

QUESTIONS TO BE SOLVED OUT:

1. What is the meaning of eco system?

2. What is the difference between food chain and food web?

3. Where a relationship can be seen benefitting both the organisms?

4. Name the parts of biotic components of eco system?

5. What is the difference between scavengers and decomposers?

6. Name the factors affecting ecosystem?

7. What is consumer and producer?

8. Give one example of food chain other than mentioned above.

9. Where are the lions present?

10. What do you understand by parasitism? Explain with one example.

11. What is the difference between food chain and food web?