Chapter 29.1- Shoot growth and development

Question 1

What are some examples of roots doing more than getting nutrients below ground?

Answer 1

Anchor roots: anchor stems to walls and to other plants

Prop roots: provides stability for the stem.

Pneumatophores: allows exchange between roots and atmosphere

Storage roots: store carbohydrates and other nutrient fruits

Question 2

What are some examples of stems doing more than just elevating leaves?

Answer 2

Water storage: cactus stems that store water

Solons: produce new individuals at nodes aboveground

Tubers: store carbohydrates such as starch ( potato is an underground stem, not root)

Question 3

What are some examples of leaves doing more than photosynthesizing?

Answer 3

Bulbs: stores food

Succulent leaves: stores water

Protection: leaves traps

Tendrils: Pea tendrils aid in climbing

Spines: protect from herbivore

Question 4

What is the three structural components of a plant? .Stem

Answer 4

Node: The point where one or more leaves are attached
Internode: The segment between two nodes
Leaf: Photosynthesis

Question 5

What are some important functions of shoot apical meristem?

Answer 5

1. elongating plant stem at the tip
2. creating leaves
3. help produce new meristems allowing branching

Question 6

How does the tips of shoots continue to divide? What genes aid it?

Answer 6

The meristem identity genes , which is expressed by chemical signals produced by cells at the tip of the stem

Question 7

How does stem elongation works in plants? What are the steps?

Answer 7

1. The shoot apical merism is established
2. stem gets elongated in the internode beneath the apical merism
3. A large central vacoule is formed
4. cells reach their final size turn into mature cells

Question 8

Why does elongating cells grow longer instead of wider?

Answer 8

• The strong cell wall ceullose around the plant it is easier to grow longer than wider

Question 9

Where does stem elongation occur in plants?

Answer 9

in the internodes beneath the shoot apical merism

Question 10

How does branches form in spore-dispersing vascular plants vs non vascular plants?

Answer 10

Vascular plants: The shoot apical meristem divides into two parts

Seed Plants: Branches grow from auxiliary buds (meristems that form at the base of a leaf)

Question 11

What is the relationship between auxilliary buds and apical meristems?

Answer 11

• they share the same meristem identity genes
• When a branch developes that auxilliary bud becomes the new shoot apical mersistem

Question 12

How did the evolution of leaves lead to changes in plant development?

Answer 12

new meristems started to evolve leaves to for capturing sunlight

leave merstems cells divide for a shorter amount of time than apical shoot stems because they are meant to capture light

Question 13

What are two structural components of leafs that effect their development and performance?

Answer 13

Primordia: small bumps that form on the sides of a shoot apical in a pattern of leaves, the pattern effects the leaves ability to photosynthesis (shaded reasons vs non shaded regions)

Bud scales: they are scales that protect shoot apical meristerms from water loss and damage to the cold.

Question 14

How does young leaves grow into mature leaves?

Answer 14

1. Intially the leaf primordia relys of cell diffusion to divide and expand
2. leaves from vascular connections with xylem and phloem to get carbohydrates and carry out photosynthesis
3. Leaves begin to elongate as proccambial cell connect the leaf to vascular connections

Question 15

How are vascular bundles arranged in vascular plants?

Answer 15

• the epidermis is the outside ring
• the phloem is the second outside
• the xylem is the third
• The tissue seperating the epirdermis and vascular bundle is the cortex
• the pith is the ground tissue inside of the ring of vascular tissues