plant anatomy and reproduction

Question 1

processes of sexual reproduction in flowering plants

Answer 1

pollination + fertilisation (fusion of male and female gametes)

Question 2

(f) sepals

Answer 2

enclose and protects the flower bud

Question 3

(f) petals

Answer 3

often colourful and fragrant, serves to attract insects and other pollinators to the flower

Question 4

(f) stamen

Answer 4

consists of a stalk (filament) tupped by an anther

Question 5

(f) anther

Answer 5

sacs where meiosis occurs and pollen grains develop. pollen grains house the cells that develop into sperm (anther, filament)

Question 6

(f) carpel

Answer 6

consists of a long slender neck (style) with a sticky stigma at its tip, at the base of the carpel is the ovary (sigma, style, ovary)

Question 7

(f) ovary

Answer 7

produces reproductive structures called ovules, each containing one developing egg and the cells that support it

Question 8

reproductive structures

Answer 8

stamen, anther, carpel, ovary

Question 9

(d) pollination

Answer 9

transfer of pollen grains from an anther to stigma

Question 10

describe the growth of the pollen tube and its entry into the ovule followed by fertilisation

Answer 10

pollen grain on the stigma germinate in response to the sugary fluid produced by the mature stigma, a pollen tube grows out from the pollen grain and the male gamete forms in thee tube. as the pollen tube grws, it secretes enzymes to digest the tissue of the stigma and style. the pollen tube grows down the style. the pollent tube enters the ovule through an opening in the ovule wall called the micropyle. within the ovule, the tip of the pollen tube absorbs sap and bursts, releasing the two male gametes. the nucleus of one of the male gametes fuses with the nucleus of the ovum to form the zygote. this is fertilisation.

Question 11

types of pollination

Answer 11

self pollination, cross pollination

Question 12

(d) self-pollination

Answer 12

transfer of pollen grains from the anther to the stigma of the same flower or of a different flower on the same plant

Question 13

(d) cross-pollination

Answer 13

the transfer of pollen grains from one plants to the stigma of another plant of the same species

Question 14

petals (wind vs animal)

Answer 14

(wind) : small/without petals, dull coloured

(insect) : large, brightly-coloured

Question 15

nectar (wind vs animal)

Answer 15

(wind) : absent

(insect) : present

Question 16

scent (wind vs animal)

Answer 16

(wind) : flowers are odourless

(insect) : flowers are fragrant

Question 17

stigma (wind vs animal)

Answer 17

(wind) : large, feathery and usually protrude out of the flower to provide large surface area to trap pollen
(insect) : small, compact and do not protrude out the flower

Question 18

stamen (wind vs animal)

Answer 18

(wind) : long pendulous filaments and protruding anthers. pollen grains easily shaken out from the anthers
(insect) : not pendulous, usually do not protrude out the flower

Question 19

pollen (wind vs animal)

Answer 19

(wind) : more abundant. have smooth surfaces and are tiny/light so that they are easily blown about by the wind
(insect) : fairly abundant. usually larger and have rough surfaces to cling onto the body of insect

Question 20

nectar guide (wind vs animal)

Answer 20

(wind) : absent

(insect) : may be present on the petals to guide insects towards the nectar