unit 7/14

Question 1

what is used for gas exchange in plants

Answer 1

the leaf because it has high surface area

Question 2

adaptations of leaf to maintain balance between gas exchange and transpiration

Answer 2

-cuticle: waxy outer layer,lipid, prevents water loss
-stomata: holes for gas exchange/transpiration
-guard cells: around stomata that can swell to close stomata or shrink to open

Question 3

adaptations of leaf for photosynthesis

Answer 3

-spongy mesophyll cells: bottom layer, spread out for CO2 use and sugar making, light independent reaction
-palisade mesophyll cells: top layer, packed for maximum surface area for light dependent reaction
-leaf vein: where xylem and phloem are

Question 4

location of xylem

Answer 4

top to bring water in for palisade mesophyll cells to do light dependent reaction

Question 5

location of phloem

Answer 5

bottom for transporting sugars away from spongy mesophyll cells

Question 6

what does a thick palisade layer mean

Answer 6

more light and more palisade can grow

Question 7

correlation between stomatal density and gas exchange/transpiration rates

Answer 7

more stomata, higher rate

Question 8

correlation between stomatal density and amount of water in environment

Answer 8

dry environments have more drastic concentration gradients- less stomata so less water is lost

Question 9

2 ways to find stomatal density

Answer 9

1. create micrograph: take leaf fold repeatedly to break cuticle, peel cuticle
   -cuticle is transparent and can be put under microscope
2. make cast with nail varnish, it hardens, leaf imprint left on cast, cast peeled to be viewed
   -multiple trials and average
   -apple to entire area

Question 10

what is transpiration

Answer 10

water evaporating out stomata of leaf-some is needed

Question 11

why is transpiration good

Answer 11

water moves through xylem cells, is used as it moves
water evaporates at top of plant
concentration gradients created so water moves up entire plant

Question 12

factors that affect transpiration rate

Answer 12

1. temperature: positive, more movement of water
2. humidity: negative-less extreme gradients
3. wind speed: positive, more movement
4. light intensity: positive- can be related to photosynthesis(more usage) and temperature

Question 13

adhesion in plants

Answer 13

water attracted to polar walls of xylem

Question 14

what is transpiration pull

Answer 14

water evaporates out plant, water moves in by roots, water moves because of cohesion, adhesion, and concentration gradients-passive process

Question 15

what is capillary action

Answer 15

cohesion and adhesion outweigh gravity

Question 16

function of xylem

Answer 16

move water around plant

Question 17

structure of xylem

Answer 17

long, empty, continuous tubes

Question 18

what happens when xylem are produced

Answer 18

they die and everything is emptied

Question 19

why is it okay for xylem to be dead and empty

Answer 19

-dont need organelles for energy-water movement is passive
-allows for quick cohesion and adhesion

Question 20

what is lignin

Answer 20

molecule that wraps around outer part of xylem to keep from collapsing

Question 21

how does water connect

Answer 21

a continuous stream, breakage leads to plant death

Question 22

what are the two groups that plants with flowers, fruits, and seeds categorized into

Answer 22

dicots: 2 embryo leaves
monocots: 1 embryo leaf

Question 23

dicots stem structure

Answer 23

-tissue distributed in ring
-xylem towards inner ring, phloem on outer; always adjacent
-pith& cortex: storage tissue for water/sugars
-epidermis
-cambium: thin layer between xylem and phloem; produces them- stem cells

Question 24

dicot root structure

Answer 24

• tissue distributed in center
  -xylem in star shape
  -phloem in between branches of xylem
  -endodermis for protection and for producing cambrium

Question 25

flower structure

Answer 25

receptacle:green bottom part that connects to rest of plant sepals: green leaves attached to receptacle that protect flower and do photosynthesis petals: brightly colored, attract pollinators stamen: male reproductive structure carpel: female reproductive structure nectaries: make nectar around base of carpel to attract pollinators

Question 26

pollinator examples

Answer 26

bees, birds, bats

Question 27

stamen parts

Answer 27

anther: makes gamete(pollin) filament: hold up anther to make easier to reach

Question 28

carpel parts

Answer 28

stigma: sticky for catching pollin style: holds stigma up to make easier for pollin to attach ovary: meiosis to make plant eggs/ovules

Question 29

what is pollination

Answer 29

movement of pollen from 1 flower to another

Question 30

methods of pollination

Answer 30

pollinators, wind, water

Question 31

benefit of pollinators over wind

Answer 31

consistency, targeted, efficient mutualistic relationship-nectar

Question 32

how does self pollination create diversity

Answer 32

not copies of self meiosis- crossing over, random assortment and segregation

Question 33

why is cross pollination better than self

Answer 33

creates more diversity

Question 34

adaptations to increase chance of cross pollination and decrease self pollination

Answer 34

1. some plants can only be pollinated by pollinators -self pollination can still happen 2. male and female parts far apart-can have different flowers 3. male and female flowers develop in different seasons - 1/2 of pop. has opposite for that season 4. genetically self- incompatible

Question 35

process of plant fertilization

Answer 35

-pollen lands on stigma -stigma enzymes break down outer part of pollen -pollen grows down tube through style to reach ovaries -sperm release -seed made and dispersed

Question 36

why are seeds dispersed

Answer 36

to make them go far away to limit competition

Question 37

methods of seed dispersion

Answer 37

wind, attaching to animals, animals eating and passing out as waste

Question 38

what is seed germination

Answer 38

beginning of growth