Plant Reproduction (T3)

Question 1

In plants, what are petals for?

Answer 1

They are large and colourful to attract insects (in insect-pollinated plants)

Question 2

What are the ‘anther’ in a plant?

Answer 2

The male sex cells.

The pollen grains are formed here and so these are the male part of the plant.

Question 3

What is the filament in a plant?

Answer 3

The filament connects the anther to the rest of the flower and together with the anther forms the stamen

Question 4

What is the stigma in a plant?

Answer 4

It is the female part of the plant which receives the pollen grains

Question 5

What is the nectary in a plant?

Answer 5

It makes nectar to attract insects (in insect-pollinated plants) and is also a reward for the insects

Question 6

What are pollen grains in plants?

Answer 6

Male gametes

Question 7

What is in the ovary of a plant?

Answer 7

Ovules (female gametes)

Question 8

What does the sepal do in a plant?

Answer 8

It provides protection to the flower when it is in bud

Question 9

What is self-pollination?

Answer 9

In pollination, pollen grains are transferred from the anther to the stigma. If this takes place within the same flower then this is known as self-pollination.

Question 10

What is cross-pollination?

Answer 10

When the pollen grains are transferred from the anther to the stigma, with the transfer taking place between different flowers.

Question 11

What happens to the pollen during the process of pollination?

Answer 11

During pollination, the pollen grows a pollen tube which digests its way through the tissue down the stigma of the flower, and carries the nucleus of the pollen into the ovary where it fuses with an ovule and fertilisation occurs.

Question 12

Name five ways in which a flower will change once fertilisation has taken place..

Answer 12

• the resulting zygote develops into an embryonic plant with a small root (radicle) and a small shoot (plumule)
• petals die and fall away
• the other contents of the ovule will become a food store for the young plant when the seed germinates
• the fertilised ovule becomes a seed of testa
• the ovary wall becomes the fruit coat and may fill with sugars

Question 13

What are three things a seed needs in order to germinate and grow into a new plant?

Answer 13

• water for chemical reactions to take place in solution
• oxygen for respiration
• warm temperature (enzymes work within specified temperature ranges and operate best at an optimum temperature)

Question 14

Briefly break down the process of a seed germinating and growing into a plant…

Answer 14

• when a seed germinates, the cells inside it grow rapidly to form the new shoot and root
• the seed contains a limited food supply of carbohydrates and lipids which it uses as fuels for respiration
• respiration provides energy for growth and development, the shoot grows upwards and leaves are formed which can carry out photosynthesis

Question 15

Describe two ways in which plants can reproduce asexually..

Answer 15

• Natural methods: a root from one plant grows a separate shoot which then grows into a new plant. The original root connecting the two plants breaks down, separating the plants. Eg: runners
• Artificial methods: growing plants from cuttings involves a piece of a plants stem with a few leaves being cut from a healthy plant and planted in damp compost. This will grow and develop into a new plant.