Plant Biology

Question 1

waxy cuticle

Answer 1

lipid outside layer of the plant, prevents it from losing water

Question 2

pallisade mesophyll

Answer 2

sublayer of a leaf that is responsible for creating sucrose

Question 3

vascular bundle

Answer 3

part of leaf that functions as the transport for water and nutrients, like a vein

Question 4

spongy mesophyll

Answer 4

spongy layer of leaf that allows for gas exchange in photosynthesis

Question 5

phloem

Answer 5

tube that helps move nutrients down from the source in the leaves to the sink in the roots

Question 6

xylem

Answer 6

tube that helps move water up the plant

Question 7

companion cell

Answer 7

cell that helps move glucose from the leaf cells to the phloem

Question 8

epidermis

Answer 8

main layer that protects the leaf

Question 9

stomata

Answer 9

part of the leaf that opens and closes to allow for gas exchange and photosynthesis

Question 10

turgor pressure

Answer 10

the pressure that keeps plant cell membranes pressed against the cell wall, created by filling the central vacuole with water

Question 11

What are the factors that impact rate of transpiration?

Answer 11

1. Light intensity (increases)
2. Humidity (decreases)
3. Wind (increases)
4. Darkness (decreases)

Question 12

sink

Answer 12

cells that use more sugar than they make (ie. root cells)

Question 13

source

Answer 13

cells that make more sugar than it uses (ie. leaf cells)

Question 14

Process of Phloem Loading

Answer 14

1. Carbs enter phloem from leaf cell
2. Water from xylem flows into phloem, building pressure to push nutrients through sieve tubes
3. Sieve tubes slow down the movement of carbs to the sink
4. Carbs are moved into the root cells through active transport
5. Water flows into xylem and then up due to higher concentration of solute at the top and transpirational pull
6. The cycle repeats

Question 15

transpirational pull

Answer 15

force that brings water up through the xylem because the water pressure is much lower at the top of the plant due to constantly losing water from transpiration

Question 16

Auxin

Answer 16

plant growth hormone that acts on the shady side of the plant, so that the plant bends towards the sunlight. it also activates enzymes to break down the cell walls and allow more water in

Question 17

Meristems

Answer 17

areas of the plant that can endlessly replicate through mitosis and allow for growth

Question 18

What are the two types of meristems?

Answer 18

the apical shoot and the apical root

Question 19

gibberellin

Answer 19

hormone that increases fruit production

Question 20

cytokines (plants)

Answer 20

hormones that can delay senescence (aging) in plants

Question 20

tropism

Answer 20

the growth of a plant towards or away from stimulus

Question 20

ethylene gas

Answer 20

gas used to ripen store-bought fruits quickly

Question 21

positive tropism

Answer 21

where the plant grows towards a stimulus

Question 22

negative tropism

Answer 22

where the plant grows away from a stimulus

Question 23

long-day plants

Answer 23

plants that only flower when exposed to light for long periods of time

Question 24

short-day plants

Answer 24

plants that only flower when daylight is 6-8 hours, but not longer

Question 25

phytochrome

Answer 25

a protein that is responsible for detecting red wave lengths of light in plants

Question 26

Pr phytochrome

Answer 26

inactive form of the phytochrome, absorbs red light, and then converts into the active form when it absorbs that light

Question 27

Pfr phytochrome

Answer 27

active form of phytochrome that switches on after the phytochrome is exposed to red light, absorbs far-red light to be deactivated

Question 28

Stamen

Answer 28

male parts of the flower, includes the filament and the anther

Question 29

Carpels

Answer 29

female parts of the flower, includes the stigma, style, and ovary

Question 30

Role of Pfr in flowering

Answer 30

in long day plants, Pfr activates flowering, while in short day plants, Pfr inhibits flowering

Question 31

radicle

Answer 31

part of the seed that is the baby root and will form the larger root after development

Question 32

cotyledon

Answer 32

the nutrient section of the seed, the largest portion

Question 33

micropyle

Answer 33

holes in the shell of the seed that allow for water absorption

Question 34

seed coat

Answer 34

outer layer of the seed

Question 35

epicotyl

Answer 35

area of the seed that will becomes the shoot, leaves, and stems

Question 36

hypocotyl

Answer 36

part of the seed that forms a connection between the cotyledon and the radicle, also known as the first leaf