T4- Structre of a Flower/ Pollination

Question 1

Anther def.

Answer 1

Where the pollen grains are made and found. These contain the male gametes (sex cells).

Question 2

Filament Def.

Answer 2

The structure that holds up the anther

Question 3

Petals def

Answer 3

These provide some protection to the structures inside the flower. Can be large and colourful to attract insects.

Question 4

Stigma

Answer 4

Where a pollen grain lands during pollination

Question 5

style

Answer 5

This links the stigma to the ovary. A pollen tube can grow through here to allow fertilisation to take place.

Question 6

ovaries

Answer 6

The ovules are found inside this structure

Question 7

Ovule

Answer 7

The female gamete (sex cell)

Question 8

What is the first part of sexual reproduction in plants?

Answer 8

pollination. This is the transfer of pollen from the anther to the sigma.

Question 9

What are the 2 ways pollination can occur?

Answer 9

insect and wind

Question 10

what is the job of pollen barbs and sticky stigma?

Answer 10

the pollen has barbs for hooking onto insect fur.

the sticky stigma is to collect pollen.

Question 11

Why do wind-pollinated flowers have a different structure from insect-pollinated flowers?

Answer 11

they do not have to attract insects to them but they do need to be exposed to the wind.

Question 12

What is the job of the exposed anthers and the feathery stigmas on the wind-pollinated flowers?

Answer 12

anthers are exposed to the wind so that pollen can easily be blown away.

stigma is feathery to catch pollen carried on the wind.

Question 13

What happens after pollination?

Answer 13

After pollination, a pollen tube grows from the pollen grain down through the style to the ovule. This allows the male gamete from the pollen grain to reach the female gamete in the ovule.

Question 14

Why are enzymes released?

Answer 14

enzymes are released that break down the stile so the pollen can pass through.

Question 15

what do ovaries develop into?

Answer 15

The ovary develops into a fruit.

Question 16

What do ovules develop into?

Answer 16

The ovules develop into seeds.

Question 17

What does Cotyledon contain?

Answer 17

contains starch (food) - for the embryo

Question 18

When starch breaks down what does it become?

Answer 18

Starch breaks down to become glucose, the glucose is used for respiration and is energy for when the plant has to grow.

Question 19

Why do seeds need to be dispersed away from the parent plant?

Answer 19

in order to reduce competition for space, light, nutrients and water.

Question 20

what are the 4 ways seeds can disperse?

Answer 20

Seeds can be dispersed by:
Wind
Water
Mechanical
Animals

Question 21

What happens after fertilisation in plants?

Answer 21

After fertilisation, the petals, stamen and sepals fall off.
The ovule turns into a seed and the fertilised egg inside develops
into an embryo plant.
Water leaves the seed so that it dehydrates and becomes dormant.

Question 22

What is Germination?

Answer 22

the sprouting of the plumule and radicle of a seed.

Question 23

What needs to happens for germination to occur?

Answer 23

For germination to occur, water enters the seed and activates enzymes.
The water also softens the testa to allow it to split.

Question 24

What does the plant do whilst the food whilst germinating?

Answer 24

Whilst germinating, the plant uses food stores in the cotyledon to provide energy for growth.

Question 25

What are the conditions required for germination?

Answer 25

Water- to activate enzymes which digest stored food
Oxygen- needed for respiration to enable the release of energy for growth
Warmth- needed for the enzymes to work effectively

Question 26

What is sexual reproduction?

Answer 26

Sexual reproduction occurs when a male sex cell (gamete) fuses with a female sex cell during fertilisation. In plants the male gamete is called pollen and the female gamete is called an ovule.

The offspring produced are genetically different from their parents.

Question 27

What is the benefit of sexual

reproduction for the species?

Answer 27

Genetic variation enables a species to

adapt to a changing environment

Question 28

What is asexual reproduction?

Answer 28

Asexual reproduction occurs when one parent produces genetically identical offspring (clones).

The offspring are produced when cells of the parent undergo a type of cell division called mitosis.

Question 29

What are the benefits of asexual reproduction for the species?

Answer 29

The offspring are genetically identical so have more chance of survival in a stable environment.

It is also quicker and less energy is lost (when the parent plant produces pollen, flowers, nectar, seeds etc).

Question 30

what are some Natural examples of asexual reproduction?

Answer 30

Bulbs (e.g. onions)

Tubers (e.g. potatoes)

Runners (e.g. strawberries and spider plants)