Lecture 16 - Plant Development

Question 1

What is Plant Development?

Answer 1

Making different parts of the plant

Question 2

Where does plant development start?

Answer 2

From a zygote

Question 3

Why is plant development important?

Answer 3

With growing population more crops for food are needed

Question 4

How is is plant development different from animal development?

Answer 4

• Some embryogenesis

- Mostly Post-embryonic development

Question 5

How is the development of lateral organs in plants?

Answer 5

It is continuous even after embryogenesis

Question 6

What is in a phytomer? [3]

Answer 6

• Axillary bud
• Internode (stem)
• Leaf.

Question 7

True or False? Continuous development of plants constantly produces phytomers

Answer 7

True

Question 8

What two organs allow for continuous development for a plant? [2]

Answer 8

• Shoot apical meristem (SAM)

- Root apical meristem (RAM)

Question 9

Which part of the shoot apical meristem do the leaves form?

Answer 9

The periphery

Question 10

Why can’t plant cells move?

Answer 10

They have a very thick cell wall

Question 11

What are the two orientations of cell division in a plant? [2]

Answer 11

• Anticlinal: At right angles to the surface

- Periclinal: Parallel to the surface

Question 12

What controls the direction of elongation in leaves?

Answer 12

• Rotudifolia (Rot)

- Anguistofolia (An)

Question 13

Hoes does Anguistofolia effect elongation?

Answer 13

Controls sideways elongation

Question 14

How does Rotudifolia effect elongation?

Answer 14

Controls leaf axis elongation

Question 15

What is embryogenesis?

Answer 15

The process by which the embryo forms and develops

Question 16

What is in a plant embryo? [5]

Answer 16

• Cotyledons
• Shoot meristem
• Hypocytol
• Radicle (Root)
• Has polarity (apical/basal)

Question 17

Why is embryogenesis important?

Answer 17

The embryo holds the body plan of the adult plant

Question 18

What are the stages of embryo shape in a plant? [5]

Answer 18

• Globular
• Heart
• Torpedo
• Linear cotyledon
• Bending cotyledon

Question 19

What is created after the 4th set of divisions?

Answer 19

The start of the epidermis lineage

Question 20

In a 8-cell stage embryo of a plant, what does the upper 4 cells become?

Answer 20

• Cotyledons

- Stem apical meristem

Question 21

In a 8-cell stage embryo of a plant, what does the lower 4 cells become?

Answer 21

• Hypocotyl

- Root

Question 22

What are WUSCHEL like homeobox (WOX) genes?

Answer 22

Act like Hox genes in plant embryogenesis

Question 23

What is the main task Wox genes perform?

Answer 23

They determine the cell division program in the cells

Question 24

What can the loss of Wox8 and Wox9 cause?

Answer 24

Abnormal cell divisions in the embryo

Question 25

What does ectopic Wox2 expression in the embryo and suspensor cause?

Answer 25

Anticlinal divisions

Question 26

Where is ATML1 primarily expressed?

Answer 26

The L1 layer

Question 27

What happens to a ATML1 mutant?

Answer 27

It is lethal since early division are defective

Question 28

Where is CUC3 expressed?

Answer 28

In the upper half of embryo cells

Question 29

What is the role of CUC3?

Answer 29

- Later turn on STM1 gene in the centre | - These centre cells become the SAM

Question 30

What happens to STM1 mutants?

Answer 30

They can not make any SAM

Question 31

What establishes the Cotyledon lineage?

Answer 31

- PHAB (adaxially) | - FIL, KAN (abaxially)

Question 32

What are the key genes during the development of the root lineage? [3]

Answer 32

- PLT1 - SRT - SCR

Question 33

What happens to a LOF PLT mutant?

Answer 33

The roots do not grow

Question 34

What during PLT2 over expression?

Answer 34

Forms an ectopic root on shoot

Question 35

How can you create a shoot in the root?

Answer 35

Express Revoluta in the root area using a Plethora promoter

Question 36

What is the role of Topless?

Answer 36

Give apical basal patterning to the embryo

Question 37

What is the role of auxin?

Answer 37

To promote cotyledon and root development and growth

Question 38

What is the role of leafycotyledon1 (LEC1)?

Answer 38

Important during Late embryogenesis

Question 39

What happens to a LOF leafycotyledon1 (LEC1) mutant?

Answer 39

The cotyledons gain trichomes

Question 40

What happens when LEC1 is overexpressed?

Answer 40

Embryos form everywhere