Chapter 38: angiosperm reproduction

Question 1

Complete flower

Answer 1

A flower which has all four organs found in flowers

Question 2

Incomplete flower

Answer 2

Does not have all flower organs

Question 3

Inflorescence

Answer 3

A flower that is actually a bunch of flowers together in one

Question 4

What is the dominant generation in an angiosperm?

Answer 4

Sporophyte

Question 5

What are all the parts of a flower

Answer 5

Sepal: the green part on a flower
Petal: the petal, usually colorful
Stamen: The male part, sticks out and contains pollen
Carpel: the female part, contains the egg

Question 6

What is the development of a male gametophyte

Answer 6

Microsporocyte: undergoes meiosis —>
Microspores: creates four of them, which then undergo mitosis —>
Each of them create a pollen grain with two sperm cells inside

Question 7

What cell types are present in the mature pollen grain?

Answer 7

Tube cell, and generative cell

Question 8

What is a pollen tube? What cell does it develop from and what is its function?

Answer 8

It develops from the Tube cell, its sole purpose is to deliver the male gametophytes to the female gametophyte

Question 9

What is the development of a female gametophyte

Answer 9

Megasporangium: undergoes meiosis —>
Megaspore: four are created, only one survives, undergoes mitosis three time–>
Creates 8 haploid nuclei which become the female gametophyte and the embryo sac

Question 10

What process is responsible for converting the microsporocyte to a microspore?

Answer 10

Meiosis

Question 11

What is the primary difference between a microsporocyte and a microspore?

Answer 11

The microsporocyte is diploid, and the microspore is haploid

Question 12

What process is responsible for converting the megasporocyte to a megaspore?

Answer 12

Meiosis

Question 13

What is the primary difference between a megasporocyte and a megaspore?

Answer 13

The megasporocyte is diploid, whereas the megaspore is haploid

Question 14

How many mitotic divisions are required for conversion of the megaspore to the female gametophyte?

Answer 14

Three

Question 15

How many mitotic divisions are required to convert the microspore to the male gametophyte?

Answer 15

Two

Question 16

Generative cell

Answer 16

The cell which divides into the two sperm in the pollen

Question 17

Tube cell

Answer 17

The cell which becomes the tube which brings the sperm to the egg

Question 18

Egg cell

Answer 18

The female gametophyte, becomes the actual seed

Question 19

Antipodal cells

Answer 19

Has no known purpose

Question 20

Polar cells

Answer 20

Become the endosperm in the fruit

Question 21

Synergids

Answer 21

Attract and guide the pollen tube

Question 22

What is meant by the term double fertilization? What does double fertilization ensure?

Answer 22

Double fertilization is the process which angiosperms use to ensure they do not go through the trouble of creating a fruit for a seed which has been not fertilized, the pollen carries two male gametophytes, one fertilizes the polar nuclei of the seed, which signals to the plant that therefore a sperm has also fertilized the egg itself.

Question 23

What part of the female gametophyte gives rise to the endosperm? What part gives rise to the fruit?

Answer 23

The polar nuclei, the ovary

Question 24

What is the function of fruit?

Answer 24

The fruit provides something for the fruit to consume while it is still young, it is a bunch of sucrose and other things the seed will need to grow until it is big enough to sustain itself

Question 25

What are the advantages and disadvantages of asexual versus sexual reproduction?

Answer 25

Advantages:
More resistant
Passing on all of its genes
Does not rely on other species for spreading its babies
Disadvantages:
Bad at adapting to different environments
Missing out on good ways of dispersing its kids

Question 26

What are the mechanisms utilized by plants to discourage self-fertilization?

Answer 26

Plants can be dioecious, which is when they will only have male/ female for one plant at a time, instead of both at the same time
They can also have their anther and carpels arranged in such a way which makes it very hard for self-fertilization to happen
Lastly they can just be self-incompatible, which is when at the atomic level the egg will reject the sperm from itself