Chapter 30 Plant Diversity 2

Question 1

What is a seed?

Answer 1

Consists of an embryo and nutrients surrounded by a protective coat

Question 2

What do all seeded plants have? (4 things)

Answer 2

• Reduced gametophytes
• Heterospory
• Ovules
• Pollen

Question 3

What is reduced gametophytes?

Answer 3

Development within the walls of spores that are retained within tissues of the parent sporophyte

Question 4

What is heterospory?

Answer 4

It is the rule among seed plants: modern seed plants are heterosporous but ancestors of seed plants are homosporous

Question 5

What does megasporangia and microsporangia produce?

Answer 5

Megasporangia -> produces megaspores -> produces female gametophytes

Microsporangia -> Produces microspores -> Produces male gametophytes

Question 6

What does the ovule consist of?

Answer 6

Consists of megasporangium, megaspore, and one or more protective integuments

• integuments are a protective layer

Question 7

What is the difference b/w gymnosperm and angiosperm in terms of integuments?

Answer 7

Gymnosperm: Has one integument

Angiosperm: Has two integuments

Question 8

What are pollen grains?

Answer 8

It contains the male gametophytes and is developed from microspores

Question 9

What is pollination?

Answer 9

Transfer of pollen to the part of a seed plant containing the ovules

Question 10

What are some advantages of seeds over spores?

Answer 10

• Remains dormant until there’s favorable conditions
• Seeds have a supply of stored food
• May be transported long distance by wind or animals

Question 11

What are gymnosperms?

Answer 11

Naked seeds typically found on cones, i.e., conifers

• seeds are exposed on sporophylls

Question 12

What are angiosperms?

Answer 12

Seeds found in fruit, also known as mature ovaries

Question 13

What are 3 key features of Gymnosperm life cycle?

Answer 13

• miniaturization of their gametophytes
• development of seeds from fertilized ovules
• transfer of sperm to ovules by pollen

Question 14

When did gymnosperm appear?

Answer 14

During the Mesozoic era cause they thrived in drier conditions

Question 15

What does a seed develop from?

Answer 15

Develops from a whole ovule

Question 16

What are the 4 types of gymnosperm phyla?

Answer 16

• Cycadophyta
• Ginkgophyta
• Gnetophyta
• Coniferophyta

Question 17

What are 3 things of the Cycadophyta?

Answer 17

• large cones and palmlike leaves
• flagellated sperm
• surviving species are endangered

Question 18

What are 3 things to remember for Ginkgophyta?

Answer 18

• consists of a single living species, Ginkgo Biloba
• Like the Cycads, this group also has flagellated sperm
• Has a high tolerance to air pollution and is a popular ornamental tree

Question 19

What are 2 things to remember for Gnetophyta?

Answer 19

• Has 3 genera: Gnetum, Ephedra, and Welwitschia
• Species vary in appearance, and some live in tropical areas while other live in deserts.

Question 20

What are 2 things to remember for Coniferophyta?

Answer 20

• Largest of the gymnosperm phyla
• Most conifers are evergreen and can carry out photosynthesis year round

Question 21

What is the most widespread and diverse of all the plants?

Answer 21

Angiosperm

Question 22

What are the 2 key adaptations of angiosperms?

Answer 22

• flowers
• fruit

Question 23

What is a flower?

Answer 23

Angiosperm structure specialized for sexual reproduction, i.e., pollination

Question 24

What are the 4 organs of a flower?

Answer 24

• sepals
• petals
• stamens
• carpels

Question 25

What are the 5 structures of a flower?

Answer 25

- filament - anther - ovary - style - stigma

Question 26

What does the sepal do?

Answer 26

encloses the flower

Question 27

What does the petals do?

Answer 27

are brightly colored and attracts the pollinators

Question 28

What do the stamen do?

Answer 28

Produce pollen

Question 29

What does the carpels do?

Answer 29

Produce ovules

Question 30

What is a filament?

Answer 30

A stalk in the stamen

Question 31

What is an anther?

Answer 31

A sac where pollen is produced in the filament in the stamen

Question 32

What is an ovary?

Answer 32

The base of the carpel that covers the ovules

Question 33

What is a style?

Answer 33

A structure that leads up to all 4 organs

Question 34

What is a stigma?

Answer 34

A structure where pollen is received

Question 35

Difference b/w complete and incomplete flowers?

Answer 35

Flowers has all 4 organs vs Flower is missing one or more organs

Question 36

Difference between radial and bilateral symmetry?

Answer 36

Imaginary lines in a flower that goes thru the central axis and divides into two equal parts vs a singular imaginary line that divides that flower into two equal parts

Question 37

What is a fruit?

Answer 37

Angiosperm formed when the ovary wall thickens and matures

Question 38

What are 3 things to remember about fruit?

Answer 38

- can be fleshy or dry - can be dispersed via water, wind, or animals - protects seeds and aid in dispersal

Question 39

What is the breakdown of the angiosperm life cycle?

Answer 39

1. The sporophyte has both male and female gametophytes. Male gametophyte is in the pollen grain while the female gametophyte is in the ovule at base of stigma. 2. Most of the flowers have a mechanism that allows for cross-pollination b/w different plants of the same species 3. A pollen grain lands on a stigma, germinates it, and the pollen tube of the male gametophyte goes down to the ovary. 4. One sperm fertilizes the eggs while the other sperm combines with 2 nuclei in the central cell to initiate the development of food-storing endosperm.

Question 40

What is double fertilization?

Answer 40

Occurs when the pollen tube discharges two sperms into the female gametophyte within an ovule

Question 41

What is a micropyle?

Answer 41

Ovule is entered by a pore

Question 42

What is a cotyledon?

Answer 42

A root and two seeds in the embryo within a seed

Question 43

When did angiosperm and gymnosperms diverge?

Answer 43

About 305 MYA

Question 44

How does bilateral symmetry affect angiosperms?

Answer 44

By affecting the movement of pollinators and reducing gene flow in diverging populations - Gives rise to increased rates of speciation

Question 45

What is the breakdown of the evolutionary history of angiosperms (4 things)?

Answer 45

- Monocots - Eudicot - Basal angiosperms - Magnoliids

Question 46

What are some characteristics of Monocots? (6 things)

Answer 46

- Embryos: one cotyledon - Leaf venation: Veins usually parallel - Stems: Vascular tissue scattered - Roots: Root system usually fibrous (no main root) - Pollen: Pollen grain with one opening - Flowers: Floral organs usually in multiples of 3

Question 47

What are some characteristics of eudicots?

Answer 47

- Embryos: two cotyledon - Leaf venation: Veins usually netlike - Stems: Vascular tissue arranged in a ring - Roots: Root system has a main root (taproot) - Pollen: Pollen grain with 3 opening - Flowers: Floral organs usually in multiples of4 or 5

Question 48

What are 3 things to remember about basal angiosperms?

Answer 48

- Amborella trichopoda - water lilies - star anise

Question 49

What are 4 things to remember about magnoliids?

Answer 49

- closely related to monocots and eudicots - Magnolias - Laurels - Black Pepper Plants

Question 50

What are 4 things to remember about monocots?

Answer 50

- More than 1/4 of angiosperm are monocots - Orchids - Grasses - Palms

Question 51

What are 3 things to remember about eudicots?

Answer 51

- More than 2/3 of angiosperm are eudicots - Large legume family - Rose family

Question 52

What are seed plants key sources of?

Answer 52

- Food - Fuel - Wood products - medicine

Question 53

What are the 6 crops that yield 80% of our calories?

Answer 53

- wheat - rice - maize - potatoes - sweet potatoes - cassava

Question 54

What are some threats to plant diversity?

Answer 54

Destruction of habitat leads to a reduction in plant population which further leads to a reduction of animal species and atmospheric CO2 absorption.