Reproduction In Plants

Question 1

Why do animals and plants reproduce

Answer 1

duced ensuring that the species does not become extinct.

Question 2

There are two types of reproduction
Name them

Answer 2

• asexual: reproduction without the formation of gametes (sex cells).

• sexual: involves the fusion of sex cells (gametes).

Question 3

Describe asexual

Answer 3

Asexual reproduction does not involve sex cells (gametes). Offspring forme genetically identical to the parent, as the process involves producing news plants by simple mitosis.

Question 4

Name the ways asexual can take place

Answer 4

Asexual Reproduction by Spores
Vegetative reproduction

Question 5

Describe reproduction by spores

Answer 5

Some plants like the moss and fern do not form seeds.The produce actually by spores. When the gametophyte matures and produces gametes, sexual reproduction occurs, because sperm fertilise ova.

Question 6

Describe vegetative reproduction

Answer 6

Vegetative reproduction does not involve the male and female sex organs of the plant; vegetative parts of the plant are responsible for producing new plants. As new plants are formed from the parent plant, by mitosis, the genetic make-up of the new plant is identical to the parent plant. Different plants have different ways in which they may reproduce by asexual means. Vegetative organs such as tubers (potatoes), bulbs (onions) and corms (garlic), may also serve as food for animals and humans.

Question 7

What are the advantages of asexual reproduction

Answer 7

Advantages of Asexual Reproduction in Plants

• Only one plant is needed.

• Offspring are genetically alike. Hence if the parent plant is well adapted to the environment, so will be the new plants.

• New plants are produced relatively quickly.

• Agents of pollination and seed dispersal are not required.

• One can select a plant with desirable characteristics, e.g. producing beautiful flowers and create identical plante m

Question 8

What are the disadvantages of asexual reproduction

Answer 8

Disadvantages of Asexual Reproduction in Plants

• A weak parent plant will produce weak offspring since they are genetically alike.

• If there are changes to the environment, the new plants may not survive since all offspring are genetically alike, e.g. vulnerability to a particular pest, or frost.

Question 9

What is sexual reproduction

Answer 9

Sexual Reproduction in Angiosperms (Flowering Plants)
Sexual reproduction occurs in most plants and animals. It involves the fusion of a sperm cell with an egg cell to form a zygote. The zygote develops into an embryo and after repeated mitosis, a new individual is formed.

Question 10

What are the Advantages of Sexual Reproduction

Answer 10

• Offspring are genetically different.

• Allows offspring to adapt to and evolve in an ever-changing environment.

• May lead to the formation of new species.

Question 11

What are the Disadvantages of Sexual Reproduction

Answer 11

.
Disadvantages of Sexual Reproduction

• It is a relatively slow process.

• Adult male and female organisms are required in order to produce gametes.

• Mutations may occur.

• In plants pollen transfer and seed dispersal requires special agents like insects, birds &

Question 12

Explain the life cycle of plants

Answer 12

Life Cycle of Flowering Plants
Inside a flower, pollen, which contain male gametes, and the ovary produces ovule, each ovule containing a female gamete. Following the fertilisation of the ovum by the sperm, a zygote is formed. The zygote develops into an embryo, which is protected inside a seed. After dispersal of the seed, and when conditions are favourable, the seed germinates and a new plant grows.

Question 13

What is pollination

Answer 13

Pollination refers to the transfer of pollen grains from the anther to the stigma.

Question 14

What is self-pollination.

Answer 14

When this occurs within the same flower, it is known as self-pollination.

Question 15

What is cross-pollination.

Answer 15

When it occurs between different flowers of the same species, it is referred to as cross-pollination.

Question 16

Describe insect pollinated flowers

Answer 16

• They are brightly coloured to attract insects.
• They have large petals which serve as a landing area for insects.
• They have a scent or nectar to attract insects.
• Pollen grains are sticky and become attached easily to the
insects.
• Anthers are firmly attached so that they cannot be broken by visiting insects.

Question 17

Describe bird pollinated flowers

Answer 17

• Flowers are long and trumpet-shaped.
• Flowers are usually red, orange or yellow.
• Flowers are not scented.
• Flowers produce nectar.

Question 18

Describe wind pollinated plants

Answer 18

• They do not have brightly coloured petals.
• They do not have a scent and do not produce nectar.
• They produce large amounts of pollen which increases the chances of pollination.
• The pollen grains are light and float easily.
• Their anthers are large and hang out of the flower. This allows the pollen grains to be carried easily by the wind.
• Stigmas are large and feathery which easily trap pollen grains