5

Question 1

Does CAM photosynthesis occur at two different cells?

Answer 1

No, only in mesophyll cells.

Question 2

How does oxygen leave the plant when the stomata is closed?

Question 3

Why doesn’t ATP get synthesized directly from the reactants of photosynthesis?

Answer 3

Because ATP requires phosphate and phosphate isn’t a reactant of photosynthesis.

Question 4

6 elements that plants can synthesize to create complex organic bio-molecules?

Answer 4

H, C, O, N, P, S

Question 5

Essential element?

Answer 5

An absolutely required element for normal growth and reproduction of plant

Question 6

Can essential elements be replaced?

Answer 6

No

Question 7

If there is a deficiency of an essential element, the plant may face?

Answer 7

Plant will exhibit specific symptoms and deficiencies, but can recover if supplied with such essential elements.

Question 8

What percentage of a forest’s biomass comes from the soil?

Answer 8

4% since most comes from CO2 and water

Question 9

Macronutrient?

Answer 9

A nutrient that is 0.1% abundance or more that are essential to create some of the essential macromolecules in the plant.

Question 10

Micronutrients?

Answer 10

Less than 0.1 abundance that is required but in a smaller abundance.

Question 11

Humus is the top part of soil which contains?

Answer 11

Contains a high density of organic matter.

Question 12

Texture and charge of soil can affect? 3•

Answer 12

•physical properties (root depth penetration and anchoring ability)
•Water holding and oxygen availability
•mobility and bioavailability of ions to plant roots

Question 13

Loam?

Answer 13

Perfect 40:40:20 ratio of sand, clay, and organic material that gives a mix of all pros and cons.

Question 14

Properties of negative ions in soil?

Answer 14

•Don’t bind to clay particles
•Readily available for plant uptake
•Easily washed away (leaching) due to bonding to water

Question 15

Positive ions properties in soils? 3•

Answer 15

•Stay in clay particles
•Not available for plant uptake
•better retained in soils.

Question 16

Root cells pump H+ outside the cell to make the outside more acidic. This create a charged gradient. How does that gradient benefit cation uptake?

Answer 16

Since the outside will be more negatively charged and the inside more positively charged and assuming that the electrical gradient is strong enough to overcome the concentration gradient, cations will diffuse from the outside to inside the cell via facilitated diffusion.

Question 17

When the pH of the soil is leveled around 6.3-7.4, then?

Answer 17

Most macromolecules will be present at high quantities.

Question 18

Most cations are more available when the pH ______ in the soil?

Answer 18

Decreases.

Question 19

Growth in a plant is limited by?

Answer 19

The scarcest resource (limiting factor).

Question 20

Aquatic environments are nutrient rich/poor?

Answer 20

Poor

Question 21

Eutrophication?

Answer 21

Gradual loss of oxygen in bodies of water, which is largely tied to the availability of nutrients.

Question 22

Major example of eutrophication?

Answer 22

When large algal blooms occur that take up most nutrients in the water, but die and are decomposed by bacteria that consume great quantities of oxygen.

Question 23

Cotransporters?

Answer 23

Membrane transport protein that diffuses anions into the root hair cell against its electrochemical gradient by connecting the anion with a diffusing proton within its electrochemical gradient. Since a lot of energy is released when a proton diffuses through the cell that the energy can be used to diffuse the anion.

Question 24

What are the differences between organic and inorganic soils?

Answer 24

•differ in mineral content (e.g. Si, P. K, trace metals, etc).
•Organic soils are more nutrient rich
•Organic soils and clay are negatively charged which affect the mobility and bioavailability of ions
•Organic soils have air spaces and can retain water.

Question 25

Out of sand, clay, and organic matter, which soil type(s) have a charged surface?

Answer 25

Clay, organic matter

Question 26

Plant uptake?

Answer 26

An active process of transporting ions from the soil to the root hair cell by cotransport.