Lecture 8: Plant Diversity 2

Question 1

What are seed-plants?

Answer 1

Vascular plants that have tissue and seeds

Question 2

What is a seed?

Answer 2

An embryo and food supply within a protective coat

Question 3

What is a feature of seed-plants?

Answer 3

They are better adapted to harsh conditions on land where it is hot and dry. In addition, the gametophyte life stage is reduced where it is protected and nourished within the sporophyte

Question 4

What is the female structure of gymnosperms?

Answer 4

1. In the female tissue, there is the megasporangium which is a diploid that produces a megaspore by meiosis.
2. Next, the megaspore germinates into a haploid female gametophyte (n)
3. After, the female gametophyte produces archegonia to develop a haploid egg (n)

Question 5

What is the ovule?

Answer 5

The whole structure of the megasporangium with the female gametophyte inside

Question 6

What is the male structure in gymnosperms?

Answer 6

1. The microsporangium (2n) produces a microspore (n) by meiosis
2. The microspore is pollen grain where the male gametophyte is found
3. Also inside, is the tube cell which is a haploid cell that produces the pollen tube.
4. The male gametophytes inside the pollen produce sperm that swims down the pollen tube

Question 7

What is a gymnosperm?

Answer 7

A vascular plant that translates to “naked seed”. They have exposed seeds in the strobili cones.

Question 8

What is the life cycle of gymnosperms?

Answer 8

1. The sporophyte, which is the dominant life stage (the pine tree), produces female and male strobili. The female is the ovulate cone and the male is the pollen cone.
2. First, the wind blows the pollen which is the male strobili and causes it to fly to the ovulate cone of a different tree.
3. Pollination occurs where the pollen reaches another tree.
4. When the pollen lands on the ovule, it germinates the pollen tube and digest it through the megasporangium tissue and through the female gametophytes to get to the archegonia and eventually the eggs
5. Once the pollen tube has made contant, the male gametophyte produces sperms that swims to get to the egg.
6. Fertilization occurs where a diploid zygote is produced and develops into a diploid embryo.
7. The ovule hardens which becomes the seed coat where the embryo will become a new sporophyte. Also, within the seed there is food that are remains from the female gametophyte.

Question 9

What are some phylum for gymnosperms?

Answer 9

1. Coniferophyta
2. Cycadophyta
3. Ginkgophyta
4. Gnetophyta

Question 10

What is the phylum coniferophyta?

Answer 10

They are conifers that translate to “cone bearing plant”. They are evergreen with needle-like greens. They are also mostly monoecious.

Question 11

What is monoecious?

Answer 11

They have both male and female parts in the same individual

Question 12

What are some genus for coniferophyta?

Answer 12

Pinus which is pine tree. Juniperus which are junipers and also picea which are spruce.

Question 13

What is the phylum cycadophyta?

Answer 13

They are cycads which translate to “palm tree plant”. They look like palm trees but are not related. They are dioecious.

Question 14

What is dioecious?

Answer 14

They have separate male and female individuals

Question 15

What is the phylum ginkgophyta?

Answer 15

They are trees that come from a japanese misspelling. They are dioecious and an example is the ginkgo bilopa which is the last of its kind.

Question 16

What is the phylum gnetophyta?

Answer 16

A plant where there is only three remaining. The genera include welwitschia, ephedra, and gnetum. Welwitschia is endemic to Namibia and Angola. Ephedra is used to make ephedrine and pseudophedrine. Gnetum is found in tropical environments and are edible.

Question 17

What are angiosperms?

Answer 17

A seed inside the fruit. Also means “contained seed”.

Question 18

What is a flower?

Answer 18

A specialized structure for sexual reproduction.

Question 19

What is selfing?

Answer 19

Self pollination where same plant pollinates itself

Question 20

What is crossing?

Answer 20

Cross pollination or different plant of the same species pollinating.

Question 21

How can pollen be transfered?

Answer 21

Direct transfer by pollinators like bees or wind pollination.

Question 22

What are floral organs?

Answer 22

Modified leaf structures

Question 23

What is the receptacle?

Answer 23

Where the flower is attached to the stem

Question 24

What are the sepals?

Answer 24

Green leafs(sometimes other colors) that enclose the flower before they open.

Question 25

What are the petals?

Answer 25

The brightly colored leaves that attract pollinators

Question 26

What is the stamen?

Answer 26

The male part of the flower that consist of the filament ,stalk, and the anther that produces the pollen

Question 27

What is the carpel(pistil)?

Answer 27

The female part of the flower that consist of the stigma (top part of the flower) that recieves the pollen, the style which is the tube, and the ovary that has the pericarp and inside has the ovule that becomes the seeds

Question 28

What are the whorls?

Answer 28

The circular patterns of the floral organs

Question 29

What is the calyx?

Answer 29

The whorl of sepals

Question 30

What is the corolla?

Answer 30

The whorl of petals

Question 31

What is the androecium?

Answer 31

The whorl of stamens

Question 32

What is the gynoecium?

Answer 32

The whorl of carpels

Question 33

What is a fruit?

Answer 33

A mature ovary that surrounds seeds.

Question 34

What are fleshy fruits?

Answer 34

Fruits where the pericarp softens as ovary matures. Such as tomatoes, plums, and grapes.

Question 35

What are dry fruits?

Answer 35

Fruits where the pericarp hardens as the ovary matures such as beans, nuts, and grains.

Question 36

What is the life cycle of angiosperms?

Answer 36

1. The sporophyte is the dominant life stage.
2. In the mature flower, it contains the anther where it contains the microsporangium. The microsporangium produces microspores through meiosis.
3. Next, the microscopre(the pollen) has the male gametophyte and tube cell.
4. Next, the ovary of the flower has the ovule which has the megasporangium which then divides through meiosis into megaspore haploids.
5. The megaspore develops into a female gametophyte which then produces a haploid egg and dikaryotic central cell made of two haploid nuclei
6. Next, pollenation occurs where the pollen of a different flower lands on the stigma.
7. The pollen tube germinates and grows down the style through the ovary and connects to the ovules.
8. The male gametophyte releases sperm that swims and reaches the ovule where double fertilization occurs. This means the sperm joins the egg and creates a diploid zygote. The other sperm joins the central cell and creates a triploid endosperm.
9. The ovary matures and becomes the fruit.
10. The ovule hardens and forms the seed coat. The zygote develops into a diploid embryo.
11. The triploid endosperm becomes food for the developing embryo.
12. The seeds the lands on fertile environment it will germinate into a new diploid sporophyte.
13. The first leaves that sprout are cotyledon which are “seed leafs”.

Question 37

What is the phylum for angiosperms?

Answer 37

Angiosperms for flowering plants.

Question 38

What are monocots?

Answer 38

1. Monocots have one leaf that sprout from the seed or one cotyledons.
2. They also have leaf veins that are parallel in one line.
3. They have vascular tissue that is scattered through the stem.
4. They have fibrous roots scattered and dont have a main root.
5. They have a pollen grain with one opening
6. They have flower organs in multiples of three

Question 39

What are dicots?

Answer 39

1. Dicots have two cotyledons that sprout from the seed.
2. The leaf veins in these are branching.
3. The vascular tissue is in a organized ring.
4. The have a main root that goes straight down.
5. They have pollen grain with 3 openings
6. They have floral organs in multiples of 4 or 5