Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biol 371 > theme 4 > Flashcards

theme 4 Flashcards

1
Q

how many essential elements are there for plants? what are the big ones?

A

elements that are required for proper functioning of the organism
-N
-P
-K
Ca
Mg
Fe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what are macronutrients

A

elements and plant needs in large quantities
-C, H, O from air
-N
-P
-K
-S
-Ca
-Mg- all of these are required to be dissolved in water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are micro nutrients

A

elements only needed in small quanities
-Cu
Cl
Ni

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the form of nitrogen that plant prefer to use

A

NO3-, but then the plant converts it back into NH4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the nitrogen cycle

A

N2 atmos–> NH4 via bacteria in soil or ammonifociation via bac of decaying matter–> NO3- via nitrification via bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

why is N important?

A

allows plant to grow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how is nitrogen taken out of the soil?

A

harvesting crops (disrupt soil) or the shifting of land for agriculture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how is nitrogen content improved in soil

A

-crop rotation
fertilizer- domination during the 1940-1970

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are lodging plants

A

during the 40-70s when fertilizer was surplus, plants grew wayyyy to tall and were prone to falling over and breaking

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how much nitrogen from fertilizer used? lost?

A

only 10% is taken by plants, 90% is lost as runoff

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what happens with excess N in water?

A

Eutrophication (algal blooms). this causes a depletion of O2. the ecosystem is harmed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

eutrophication

A

the enrichment of ecosystems with chemical nutrients such as N and P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the grains that are found in soil?

A

sand 0.02-2mm
silt 0.02-0.002mm
clay <0.002

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is soil solution

A

a combo of water and its dissolved components that coat particles and fills pore spaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do clay and humus particles do to water moles?

A

negatively charges them- makes it alkiline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is cholorosis

A

the yellowing od plant tissues due to a lack of chlorophyll

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how are minerals (cations) exchanged between roots/soils

A

the roots produce H+ ions which will enter the solid, and displace the nutrients (K+, Ca2+ and Mg2+) which in turn are uptaken by the roots
or the roots and CO2 via respiration which are turned into H2CO3 when interacting with H2O, the H+ from this mole displace the cations in the soil and are uptaken by the roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how are anions exchnaged between soil and roots

A

anions move freely in the negatively (alkaline) charged soil and easily move into the roots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what is the common pH of soil

A

8-9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is alkaline soil

A

a basic soil whcih can easly leach anions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is an acidic soil

A

a soil which cations leach out easily

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

passive transprt

A

requires no energy to move a substance. it moves down the [] gradient (with the membrane potential)
-eother moves across the membrane )O2, H2O or CO2) or through a protein

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

active transport

A

requires the expenditure of ATP to move a substance (against the gradient)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are two mechanisms that plants use to increase nutrient uptake

A

root hairs- greatly increase SA
-Mycorrhizae- a symbiotic relationship with fungus and roots (fungus mobilizes phosphorous)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is humus?

A

the top layer of soil (the most important)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what structures are used to transport nutrients over long distances

A

xylem and phloem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

where does short travel distance occure in plants

A

at roos and in between membrane s

28
Q

how much water is lost via transpiration

A

90%

29
Q

what is water potential

A

the driving force of water movent
the sum of solute potential and pressure potential

30
Q

what are aquaporins

A

chanel protines that promote the movement of water across a hydrophobic membrane

31
Q

how does water move in relation to water potential

A

from areas of high potential to areas of low potential

32
Q

what happens when a solute is added to a water system

A

the water potential is lowered

33
Q

what happens when pressure is added to a water system?

A

the potential is increased (when applying pressure)\
if pressure is removed, then the water potential is lowered

34
Q

where is water and solutes sorted within a plant cell

A

the central vacuole

35
Q

how do things entre the central vacuole

A

by passing through the tonoplast (the membrane

36
Q

plasmolysis

A

wilting when a plant loses water due to dry soil with a low potential

37
Q

what happens to a plant cell if there is a low water potential in soil

A

the vacuole will actually take up more solute from the environment to create a lower water potential inside the cell and have water flow into the cell to maintain turgor pressure

38
Q

what are the two pathways that water and nutrients travel through the roots and into the xylem?

A

apoplastic and symplastic

39
Q

what is apoplastic movement

A

water moves THROUGH cell walls

40
Q

what is symplastic movement

A

movement of water through cells via their cytoplasm and plasmodesmata

41
Q

what are plasmodesmata

A

connections between cells

42
Q

what is the casparian stripe? what does it do?

A

endodermal cells which actively pump ionos across a membrane
a selectively permeable wall/barrier to apoplastic water and solute movement. all intracellular routes are sealed off and all nutrients are pushed into the cell for a ‘screening’. this occurs right before the xylem

43
Q

is apoplastic or symplastic faster?

A

apoplastic. this is because nutrients do not need to move through think cytoplasm

44
Q

why do apoplastic water and solutes into the cell at the endodermis? (strip)

A

to allow to the plant to regualte its ion uptake and restrcs any solutes from flowing back as its made of a waxy substance

45
Q

how is water and nut taken into the apoplastic route vs the symplastic route

A

apo= passive
sympla= generally active, but can be passive depending the plants needs

46
Q

what is the main mechanical properties of water

A

cohesion-tension allows for water moles to stick together and be transported up the xylem in one continuous line

47
Q

transpiration

A

the mechanism which pulls water up the xylem (application of negative pressure). it evaporates outside the stomatal opening of leaves.
water in the roots 9high P) is pulled to areas of low pressure (higher vasculature)

48
Q

what is guttation

A

when the root pressure is so string that enough water is pushed through the xylem so that water droplets from from the stomatal opening
overall the high pressure in root systems contribute to the upward movement of water in a plant

49
Q

what company is found in the xylem that assists in the maintenance of its structure?

A

lignin- a heavy organic compound that helps support the xylem from the negative pressure

50
Q

what does the phloem transport?

A

long distance of sugar and other nutrients in the form of sap

51
Q

in what directions does the pholem and xylem transport nutrients?

A

Xylem is only upwards
phloem is multi-directional

52
Q

what drives the flow of sap in the phloem?

A

the presser difference between the sources of sugar and the sinks

53
Q

what is a source and a sink?

A

source: where substances are loaded into the phloem
-leaves
sink: where organic substances are unloaded (natural depletion area of substances)
-roots and flower heads

54
Q

what are sieve tubes and what are they connected to

A

sieve tube are small tubes that make up the pholem
they undergo partial death and are attached to companion cells which contain all the necessary components for life (to keep the overall phloem body alive)

55
Q

what is contained in the companion cells?

A

nucleus
central vacuole
some mitochondria
rough ER (with ribosomes)
golgi bodies

56
Q

what is retained in the mautre sieve tube?

A

mitochonria
smooth ER
plastids
plasma membrane

57
Q

what kind of division occurs that generate the sieve tube and its companion cell from the phloem mother cell

A

asymetrical: the formation of 2 cells with distinct roles

58
Q

what is the process of forming the sieve tube and the companion cell?

A

apoptosis

59
Q

how does sugar (sucrose)enter the phloem?

A

via active transportation. generally smaller sugar molecules like sucrose and glucose are transported through plasmodesmata into the companion cells where they are synthesized into larger molecules. the larger molecules then are moved into the sieve tubes

60
Q

what is pressure flow mechanims

A

the movement of substances via bulk flow from the source to a sink or from an area of high pressure ([]) to low pressure ([])

61
Q

where does gas exchange occur?

A

through the stomata

62
Q

what leaf layer reducced water loss

A

the cuticle (a waxy layer)

63
Q

what challenges does the plant face with gas exchange

A

getting adequate CO2 but needing to balance the amount of water in its vasculature
-either transpiration (H2O and nutrient uptake ) or phosyn is compromised)

64
Q

how is to stomatal opening controlled?

A

by the [K+]. the flow of high [K+] called for water to follow into the guard cells and increases pressure. this opens the pores. low [K+] causes water to flow put, closing the pores;

65
Q

when is the stomata open vs closed?

A

open to promote phosyn and when blue light is high
close where the plant is under water stress–> signal initiated by the roots

66
Q

what is the chemical signal that causes guard cells to close?

A

mesophyll abosrbs ABA which signals for the closure

67
Q

what is the mesophyll and its function?

A

the cells found within a leaf. comprised of the spongy cells and the upper dermis. promotes the evaporation of water

Biol 371 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions