week 3 quiz

Question 1

parts of the root system?

Answer 1

roots: anchoring the plant, absorbing minerals & water,
storing carbs, increase SA:V ratio
root hairs:increase SA:V ratio
myco fungi: increase SA:V ratio

Question 2

major plant cells?

Answer 2

parenchyma, collenchyma, sclerenchyma, water-conducting cells of the xylem, & sugar conducting cells of the phloem

Question 3

parenchyma

Answer 3

*performs most metabolic processes (ATP)
*large central vacuole
*thin & flexible cell walls (easy transport)
*lacks secondary walls
*clumps of chloroplasts

Question 4

sclerenchyma

Answer 4

*heavy walls for strength, thickness caused by lignin
* dead at functional maturity
* two types:
1) sclereids- short and irregular in shape; also have thick lignin walls
2) fibers

Question 5

water-conducting cells of xylem

Answer 5

*dead & perforated tubes carrying water to the top of the plant
*two types:
1) tracheids: tiny, dead and lignified at maturity; long, thin, with tapered ends in xylem of all vascular plants
2)vessel elements: big and dead at maturity

Question 6

sugar conducting cells of the phloem

Answer 6

*alive at maturity but lack organelles
* sieve-tube elements

Question 7

parts of the leaf (top to bottom)

Answer 7

1)cuticle
2)upper epidermis
3)palisade layer or parenchyma
4)spongy layer
5)lower epidermis: contains 2 guard cells which make up stomata (where carbon dioxide comes in for photosynthesis)

Question 8

parts of the shoot system?

Answer 8

reproductive shoot
node
internode
leaf: blades and petioles
stem

Question 9

Steps of cellular respiration?

Answer 9

1)glycolysis-> where glucose first gets broken down, & it produces some ATP
2) mitochondria does oxidative phosphorylation= ATP; produces 36-38 ATPS due to oxygen

Question 10

what is lost at every level of the energy flow chart?

Answer 10

heat is lost

Question 11

what do enzymes in our cells do?

Answer 11

lower the activation energy to produce ATP

Question 12

where does H20 enter and leave the plant?

Answer 12

enters at roots, along with nutrients like nitrogen and phosphorous

Question 13

where does CO2 enter and leave the plant?

Answer 13

enters at leaves, leaves at roots

Question 14

where does o2 enter and leave?

Answer 14

enters at roots, leaves through leaves

Question 15

what is the apoplastic route?

Answer 15

materials don’t have to cross membrane, but have to go through casparian strip

Question 16

what is the symplastic route?

Answer 16

pass through plasmodesmata

Question 17

what is transmembrane transport?

Answer 17

-proton pump
-H+/sucrose cotransporter
-ion channels

Question 18

what is transpiration?

Answer 18

drives the transport of water & minerals from roots to shoots via the xylem; loss of water through stomata

Question 19

what is the casparian strip?

Answer 19

selective of materials that get to the vascular bundle; membrane isn’t always successful-> plant diseases

Question 20

what is the cohesion-tension hypothesis?

Answer 20

transpiration & water cohesion pull water from shoots to roots-> negative pressure generated in the airspace to move water out through stomata-> the rate of transpiration is regulated by stomata

Question 21

what is turgor pressure?

Answer 21

open& close stomata; pore-closed= flaccid-> isotonic; pore-open= guard cells turgid-> hypotonic

Question 22

how do stomata open & close?

Answer 22

changes in turgor pressure due to uptake of K+ in guard cells, water wants to come in to dilute, causes turgidity & stomata opens; proton pumps generates membrane potential so K+ moved in to replace protons

Question 23

why does the proton pump activate?

Answer 23

-blue light-> chloroplast pigments absorbs blue & red
-CO2 depletion
-circadian rhythm
-humidity