Chapter 30 terms/concepts

Question 1

Explain how seeds and pollen grains are key adaptations for plants

Answer 1

Seeds remain dormant until conditions are favorable for germination, while also having a supply of stored food , and may be transported long distances by wind or animals (advantages of a pollen grain). Since nonvascular plants released flagellated sperm in water and therefore require it to reproduce, seed plants are able to survive drier climates given that their pollen can be transported outside of water environments, and seeds can remain dormant

Question 2

Other adaptations besides seeds for seed plants + why they are advantageous

Answer 2

Reduced gametophytes, heterospory, ovules, and pollen

These adaptations helped plants cope with conditions such as drought and exposure to UV light, while also freeing them from requiring water for fertilization, enabling reproduction under a broader range of conditions

Question 3

Heterospory

Answer 3

When a plant produces two types of spores, which develop into either male or female gametophytes

Question 4

Describe the major groups of gymnosperms

Answer 4

Phylum Cycadophyta: have large cones and palmlike leaves. They have flagellated sperm (unlike most seed plants, which suggests they are direct descendants of seedless vascular plants that had motile sperm)

Phylum Ginkgophyta: Also have flagellated sperm like cycads. Fan-like leaves that turn gold in autumn. They have fleshy seeds that smell rancid when they decay, so most people only plant pollen-producing plants.

Phylum Gnetophyta: Some tropical and some desert species. Different morphologies, but grouped based on molecular data

Phylum Coniferophyta: largest phylum of gymnosperms - have large woody cones, but some have small fleshy cones. Most are evergreens and retain needle-like leaves throughout the year

Question 5

Compare and contrast gymnosperms and angiosperms

Answer 5

Key difference between gymnosperms and angiosperms is how their seeds are developed. The seeds of angiosperms develop in the ovaries of flowers and are surrounded by a protective fruit.

Gymnosperm seeds are usually formed in unisexual cones, and plants lack fruits and flowers.

Question 6

Discuss how the flower gives angiosperms a reproductive advantage over gymnosperms

Answer 6

Since flowers require pollinators (like bees, and other animals) to transfer pollen from one flower to the sex organs of another, it is more of a directed process than the wind-dependent pollination cycle of gymnosperms.

Question 7

Sepals

Answer 7

Usually green, enclose the flower before it opens, used to protect the maturing flower before it “hatches”

Question 8

Petals

Answer 8

Brightly colored leaves interior to the sepals, these mainly function as a location of attraction towards pollinators

Question 9

Anther

Answer 9

(part of the Stamen) Microsporophylls - produce microspores that develop into pollen grains which contain male gametophytes

Question 10

Filament

Answer 10

(part of the Stamen) Supports the anther

Question 11

Stigma

Answer 11

Part of the pistil - sticky surface that receives pollen

Question 12

Style

Answer 12

Part of the pistil - leads from stigma to the ovary

Question 13

Ovary

Answer 13

Part of the pistil - contains one or more ovules

Question 14

Fruits

Answer 14

Develop when the ovary wall thickens and matures

They protect seeds and aid in dispersal

Mature fruits can be either fleshy or dry

Question 15

Monocot

Answer 15

Have one cotyledon

and other distinguishing characteristics (see figure 30.16)

Question 16

Eudicots

Answer 16

True dicots - have 2 cotyledon

and other distinguishing characteristics (see figure 30.16)

Question 17

How does human welfare depend on seed plants?

Answer 17

Loss of tropical rainforests would contribute to global warming (which would then have negative effects on human societies and animal wildlife). Also, humans depend on many seed plants for food and other products, and the loss of some major food products would have dramatic effects on the well-being of humans for obvious reasons