LESSON 11: PLANT GROWTH

Question 1

Plant growth can be affected by many things including…

Answer 1

-The type of seed or species of plant
-The quality of the soil
-The amount of water present
-The amount of light

Question 2

In order to produce new roots…

Answer 2

cells in the plant’s stem must undergo both growth and differentiation

Question 3

Growth

Answer 3

the process of increasing in size (i.e. blowing up a balloon)

Question 4

increase in height comes from

Answer 4

apical meristems.

Question 5

Apical meristems

Answer 5

regions of actively dividing cells found at the apices of plants (i.e. tips of their buds, stems, and roots)

Question 6

All growth from the apical meristems is called

Answer 6

PRIMARY GROWTH.

-Primary growth always increases the height of a plant, but not its width

Question 7

what arises from lateral meristems

Answer 7

SECONDARY GROWTH

Question 8

-Lateral meristems

Answer 8

areas of actively dividing tissue in the stems and roots

–Secondary growth increases the girth (width) of a plant

Question 9

Primary Growth

Answer 9

Primary growth increases the length of a plant shoot or root
-It begins as the cells of the apical meristems divide by mitosis (this increases the # of cells)
-Once cell division has occurred, each cell grows longer and begins to specialize which results in the production of different cell types
-Cell types can include: parenchyma (most abundant type of ground tissue), epidermal, or vascular cell types

Question 10

what does The shoot apical meristem produce?

Answer 10

he tissues that form stems, leaves, and organs responsible for sexual reproduction (i.e. flowers in angiosperms)

Question 11

What doesroot apical meristem produces?

Answer 11

produces the cells of the root cap and all other cell types in the root

Question 12

What are all tissue formed from apical meristems called?

Answer 12

primary tissue (i.e. xylem & phloem that arise from apical meristem are called primary xylem and primary phloem

Question 13

Primary growth in woody planst only occur when…

Answer 13

only happens in woody species after the plant’s first year.

Question 14

What does secondary growth arises from?

Answer 14

arises from a lateral meristem

Question 15

what tissues form from laterial meristem?

Answer 15

all tissues that are formed by it are called secondary tissues.

Question 16

Lateral meristems are never…

Answer 16

Lateral meristems are never at the apex of the shoot or root

Question 17

Exampel of lateral meristems?

Answer 17

Vascular cambium is an example of a lateral meristem

Question 18

After the first year of growth, primary and secondary growth happen…

Answer 18

simultaneously

Question 19

Do woody speices grow in length and width?

Answer 19

Woody species continue primary growth and increase in length (height) and they also increase in diameter through secondary growth from two lateral meristems (the cork cambium & the vascular cambium)

Question 20

Cork cambium produces…

Answer 20

the cells that form the bark and vascular cambium produces secondary xylem and phloem

Question 21

Photoperiodism

Answer 21

a plant’s response to changes in day length.

Question 22

Macro

Answer 22

nutrients needed in large quantities

Question 23

Micro

Answer 23

nutrients needed in small quantities

Question 24

The main environmental factors that affect plant growth and development are:

Answer 24

-Light (i.e. seasonal changes in light,
photoperiodism)
-Water
-Temperature (i.e. specific temperature
range for cellular processes)
-Nutrient availability (i.e. soil
composition/pH, macronutrients vs.
micronutrients)

Question 25

tropism

Answer 25

a directional change in growth or
movement in response to a stimulus

Question 26

phototropism

Answer 26

a change in direction of a
growing plant in response to light

Question 27

Other types of tropisms include

Answer 27

gravitropism and thigmotropism

Question 28

thigmotropism

Answer 28

a directional change in
growth pattern in response to touch

Question 29

gravitropism

Answer 29

a directional change in
growth pattern in response to gravity

Question 30

5 plant growth regulators

Answer 30

Auxins, gibberenllins, cytokins, ethylene, Abscisic Acids

Question 31

apical dominance

Answer 31

the condition in which
most shoot growth arises from the apical
bud and not lateral buds

Question 32

Auxin

Answer 32

groups of compounds that act in similar ways on plant growth and differebtation

-Promote cell elongation

Question 33

Gibberenllins

Answer 33

• promote cell divison and cell elongation

-Can sometimes play a role in flowering and fruit prodcution

-smaller plants are that way because of low levels of gibberenllins

Question 34

Cytokins:

Answer 34

-Promotes cell divison

-found in the tissue that are actively dividng like meristems and many other tissues

Question 35

Ethylene

Answer 35

regulates fruit rippening and stress responses in many plants

Question 36

Abscisic acid

Answer 36

Abscisic acid inhibits growth and promotes dormancy in many species. It also
induces the closing of stomata during water stress.

Question 37

senescence

Answer 37

developmental events in
a plant tissue or organ from maturity
to death