Lecture 25- Plant Form and Function

Question 1

what does a stem consist of? (4)

Answer 1

nodes
internodes
axillary bud
apical bud

Question 2

what does the axillary bud do?

Answer 2

produces clusters of flowers or branches
lateral branches develop from axillary or lateral buds

Question 3

what does the apical bud on a plant do?

Answer 3

primary growth
elongation of young shoot

Question 4

what occurs with apical dominance?

Answer 4

maintains inactivity in most axillary buds

Question 5

what does the node do?

Answer 5

site of cellular activity
where leaves attach

Question 6

where is the internode on the branch?

Answer 6

area between leaves

Question 7

what does the petiole (stalk) do?

Answer 7

connects the leaf to the stem

Question 8

what are the functions of a root? (3)

Answer 8

anchors the plant
absorbs minerals and water
stores carbohydrates

Question 9

why do roots have lateral roots? ex. root hairs

Answer 9

increase SA so that more nutrients can be absorbed

Question 10

what cells are found in the root? (6)

Answer 10

tracheids
parenchyma
vessel elements
companion cells
sclerenchyma cells
fiber cells

Question 11

primary growth of roots occurs behind the root tip in 3 zones, what are they?

Answer 11

cell division
elongation
differentiation/ maturation

Question 12

the primary growth of roots are in line with what in order to facilitate transport?

Answer 12

xylem

Question 13

why is the root tip covered by a root cap? (4)

Answer 13

protects as the root pushes through the soil
produces slime to lubricate the dry soil
produces signals to attract beneficial microbes
senses gravity

Question 14

what is the function of the shoot (stem and leaves)? (4)

Answer 14

photosynthesis
transpiration
transport
reproduction

Question 15

there are two types of water conducting cells that die at maturity within the xylem, what are they?

Answer 15

tracheids (small holes)
vessel elements (large holes)

Question 16

what is an example of a sugar conducting cell within the phloem?

Answer 16

sieve tube

Question 17

what does the sieve tube consist of?

Answer 17

sieve plate
companion cell

Question 18

how does the SAM increase stem length?

Answer 18

cells divide quickly at the shoot tip then get pushed down after dividing, this elongates the shoot

Question 19

what are the functions of leaves? (4)

Answer 19

intercept light
exchange gas
dissipate heat
defend plant from herbivores and pathogens

Question 20

what are the two leaf types?

Answer 20

simple leaf
compound leaf

Question 21

what are the two types of compound leaf?

Answer 21

pinnate (leaves arent divided into leaflets)
palmate

Question 22

what is the difference between pinnate and palmate compound leaves?

Answer 22

with palmate all the leaves come from one location
with pinnate the leaves are all attached along the stem

Question 23

why do cacti have spines?

Answer 23

because there is barely anything to eat in the desert the plant needs to protect itself because it has a lot of predators

Question 24

in leaf structure they have something called a mesophyll, what are the two types of mesophyll?

Answer 24

palisade
spongy

Question 25

what do stoma do for the leaf?

Answer 25

allow CO2 and O2 exchange (gas exchange)
allow for water to evaporate

Question 26

when is the stoma open and when is it closed? why?

Answer 26

open during the day
closed at night
closed at night because since its dark out there is no sun and therefore cant undergo photosynthesis, so they keep all the CO2 in