MODULE ONE

Question 1

Which organism is the first ancestor to plants?

Answer 1

Green Algae

Question 2

Which classes make up Bryophytes?

Answer 2

Liverworts
Mosses (1&2)
Hornworts

Question 3

Which is the oldest evolutionary group that make up Bryophytes?

Answer 3

Liverworts

Question 4

Which class is most closely related to Green Algae?

Answer 4

Liverworts

Question 5

List the classes that make up Bryophytes from least to most diverse.

Answer 5

1. Hornworts
2. Liverworts
3. Mosses

Question 6

Describe the physical characteristics of Liverworts.

Answer 6

Plant bodies are often flattened

Question 7

Describe the physical characteristics of Mosses.

Answer 7

Mosses are the most diverse class under bryophytes and come in different shapes, colours, and sizes

Question 8

Describe the physical characteristics of Hornworts.

Answer 8

Plant bodies are often flattened, also grow ‘horns’ to reproduce

Question 9

How to Bryophytes differ from Vascular Plants?

Answer 9

• Small in size
• Lack vascular tissue
• Lack true roots, only rhizoids (tiny filamentous ‘roots’)
• No or very limited cuticle

Question 10

What does vascular tissue consist of?

Answer 10

Xylem & Phloem

Question 11

What is the function of the Xylem?

Answer 11

Transports water through the tissue upwards

Question 12

What is the function of the Phloem?

Answer 12

Photosynthetic tissues move down to where the plant is growing

Question 13

Describe the characteristics of the Xylem and the consequences of such.

Answer 13

Xylem cells are very strong and acts as a backbone for the plants resulting in non-woody(herbaceous) plants to grow relatively tall

Question 14

Describe water transport in Bryophytes.

Answer 14

Water permeates from cell-to-cell passively. Results in less fast transportation and restricts the maximum size of the plant.

Question 15

Why are Bryophytes typically small?

Answer 15

They do not have xylem (vascular tissue), their cells are less strong and lack a back bone. The way they transport water (cell-to-cell) is slow and less efficient which is another factor that contributes to this characteristic. They lack enforced cells or tissue to keep them upright beyond a small maximum size

Question 16

Do Bryophytes have true roots? Explain:

Answer 16

They lack true roots, but have rhizoids (tiny filamentous ‘roots’)
- it is good enough for anchoring
- not great for uptake of resources
- unlike vascular plants, rhizoids are not made up of vascular tissue

Question 17

Since Bryophytes either have no or very limited cuticle, what are the consequences of such adaptation?

Answer 17

Quick loss & quick uptake of water along whole surface
Bryophytes prefer wet/moist ecosystems

Question 18

List the steps in the life cycle (generalized alternation of generations) of Bryophytes in order.

Answer 18

1. Gametes (egg &sperm)
2. Fertilization
3. Zygote
   - mitosis
   4.Embryo
   -mitosis
4. Sporophyte
5. Meiosis
   7.Spores
   -mitosis
6. Gametophyte
   -mitosis
7. Gametes (repeat)

Question 19

What is the male reproductive organ in Bryophytes called?

Answer 19

Antheridia/Antheridium

Question 20

What is the female reproductive organ in Bryophytes called?

Answer 20

Archegonia/Archegonium

Question 21

How many eggs does each archegonium hold?

Answer 21

One

Question 22

How do Bryophytes take up water?

Answer 22

Shoots
Leaves
Rhizoids

Question 23

Where are spermatozoids produced in Bryophytes?

Answer 23

Antheridium/Antheridia

Question 24

What is the name of the structure supporting the spore capsule?

Answer 24

Seta

Question 25

What is the function of the cuticle?

Answer 25

It is a thin layer used in the vast majority of plants to seal leaves against desiccation. Also a hydrophobic layer.

Question 26

Describe the characteristics and function of the the spermatozoid.

Answer 26

It has two self-propelled flagellae and chemo-detectors which allow it to swim over short distances towards the female gametophyte to fertilize the egg cell.

Question 27

What are the conditions for fertilization to occur in Bryophytes?

Answer 27

Water dependent, but a thin water film is enough

Question 28

When do chemotaxis occur in the Bryophyte life cycle?

Answer 28

Spermatozoids can chemically taste their environment to find the female archegonium

Question 29

What components make up a Sporophyte?

Answer 29

Seta Spore Capsule

Question 30

Which parts of the Bryophyte life cycle is diploid?

Answer 30

Sporophyte -seta -wall of spore capsule

Question 31

Which parts of the Bryophyte life cycle is haploid?

Answer 31

Gametes (Egg and Sperm) Spores Gametophyte Antheridia Archegonium Protonema Spermatozoid

Question 32

Which generation(s) are short lived in Bryophytes?

Answer 32

The diploid part -Sporophyte

Question 33

Which generation(s) are dominant in Bryophytes?

Answer 33

The haploid part -Gameophyte

Question 34

Which unit of the life cycle in Bryophytes is wind dispersed?

Answer 34

Spores

Question 35

Which group among bryophytes is most closely related to lycophytes

Answer 35

Hornworts

Question 36

Which parts of a plant are photosynthetic in moss?

Answer 36

Gametophyte Protonema

Question 37

Which unit of the following life cycle is mobile and self-propelled?

Answer 37

Spermatozoid

Question 38

Where is the egg cell in Bryophytes contained in?

Answer 38

Archegonium/Archegonia

Question 39

Which group within bryophytes is most closely related to vascular plants?

Answer 39

Hornworts

Question 40

What is the name of the structure from which female and male gametophytes grow in bryophytes?

Answer 40

Protonema

Question 41

Which group among the bryophytes is evolutionary the youngest?

Answer 41

Hornworts

Question 42

What are the differences between water dependent dispersal and wind-dependent dispersal in Bryophytes?

Answer 42

Water dependent dispersal is short distance is used for spermatozoids. Wind dependent dispersal is long-distance and is used for spores.

Question 43

In germination, how is the sex of the gametophyte decided?

Answer 43

Half the spores in the spore capsule have the genes to produce female gametophytes, and the other half has the genes to produce male gametophytes.

Question 44

How do Bryophytes in the desert survive?

Answer 44

They have adapted to survive the complete loss of water. When there is no water, the plant goes into a 'hibernation' type state where they do not grow, reproduce, or photosynthesize. When it rains, they uptake water quickly and resume growth.