blended - plant sex

Question 1

what is the other name for pollen grain

Answer 1

microspore

Question 2

what is the tapetum

Answer 2

specialised layer of nutritive cells (within the anther)

Question 3

what is the other name for ovule

Answer 3

megaspore

Question 4

what must occur before fertilisation can take place

Answer 4

pollination

Question 5

what controls the germination of the pollen grain(growth of pollen tube)

Answer 5

pollen tube nucleus

Question 6

how does the pollen grain enter the ovary

Answer 6

style and ovary wall are digested by hydrolase enzymes

Question 7

when does the pollen tube stop growing

Answer 7

once it reaches the micropyle

Question 8

what moves down the pollen tube behind the pollen tube nucleus

Answer 8

2 male gametic nuclei

Question 9

what does the zygote (2n) form during double fertilisation

Answer 9

mitosis = embryo (radicle + plumule)

Question 10

what does a cotyledon do

Answer 10

stores food for embryo

Question 11

what does the primary endosperm nucleus (3n) form during double fertilisation

Answer 11

mitosis = food storage tissue

Question 12

what does the integuments form during double fertilisation

Answer 12

testa / seed coat

Question 13

what does the ovary wall form during double fertilisation

Answer 13

fruit wall

Question 14

what does the ovules form during double fertilisation

Answer 14

seeds

Question 14

how is the primary endosperm nucleus (3n) formed

Answer 14

1 male gamete fuses with 2 polar nuclei

Question 14

how is the zygote (2n) formed

Answer 14

1 male gamete + female gamete

Question 15

what is a monocotyledonous seed

Answer 15

have only one cotyledon. Their main food store is the endosperm

Question 15

what is a dicotyledonous seed

Answer 15

have two seed leaves or cotyledons which act as food stores

Question 16

what are the conditions for germination

Answer 16

1. absorb water through micropyle
   
   • causes testa to split (increases vacuole size)
2. absorb O₂ through micropyle
   
   • for aerobic respiration
3. warm temperature + light

Question 17

how is glucose released for respiration in germination

Answer 17

endosperm starch is hydrolysed by amylase + maltase

Question 18

what triggers production of amylase + maltase

Answer 18

water absorption

Question 19

how is germination initiated in monocotyledons 1

Answer 19

plant hormone gibberellin

Question 20

how is germination initiated in monocotyledons 2

Answer 20

1. water absorbed through micropyle
2. gibberellin carried to outer layer of endosperm(aleurone)
3. DNA transcribed into mRNA = hydrolytic enzymes
4. aminoacids needed to synthesise proteins are stored in aleurone. released through hydrolysis
5. glucose diffuses to embryo