name _________________________ AGRO 1033, T2, S2007

____ Which of the following is NOT a C4 crop with regard to photosynthesis?

A. corn B. soybean

C. sugarcane D. grain sorghum

____ Carbon dioxide losses from plants occur from both:

A. respiration and mitosis B. respiration and photorespiration

C. photorespiration and photosynthesis C. photorespiration and photolysis

____ Gaseous diffusion into leaves is regulated by what leaf structures?

A. golgi valves B. vascular bundles

C. chloroplasts D. stomates

____ The ideal soil pH for growing crops is around:

A. 3.5 B. 4.5 C. 6.5 D. 8.5

____ Photorespiration is higher in:

A. C3 than C4 crops B. C4 than C3 crops

C. C.A.M. than C3 crops D. C.A.M. than C5 crops

____ Loess is a:

A. starch storage organ in plants B. by-product of photosynthesis

C. soil parent material D. term describing soil texture

____ A 50 lb bag of 10-26-8 fertilizer has how many lbs of P?

A. 10 B. 26 C. 4 D. 13

____ The grade of a 16-24-8 fertilizer is:

A. 16-24-8 B. 8-12-4

C. 2-3-1<ratio! D. 2-3-1

____ Conservation tillage soil management:

A. should be approved by the USDA prior to implementation

B. must leave 90% or more residues on the soil surface

C. do not involve any disturbance of the soil by implements

D. must leave 30% or more residue on the soil surface

____ Which one of these nutrients is considered a plant micro-nutrient?

A. C B. Zn C. N D. P

____ Red and gray colors in soils are due to the effect of what on soil color?

A. Fe B. N

C. organic matter C. temperature

name______________________________ AGRO 1033, T2, F2007

____ The ‘Calvin cycle’ of plants is located in what cell organ?

A. mitochondria B. vacuoles

C. chloroplasts D. nucleus

____ Potassium is taken up by plants as:

A. KCl B. K⁺ C. KNO₃ D. KH₂PO₃

____ Plant nutrients such as Ca and Mg are referred to as:

A. secondary nutrients B. primary nutrients

C. micronutrients D. non-essential nutrients

____ In C3 plants, the majority of the chloroplasts are located in the:

A. vascular bundle B. guard cells

C. palisade mesophyll D. spongy mesophyll

____ If a farmer needed to apply 90 lbs N/acre, how much 45-0-0 would be needed?

A. 90 B. 45 C. 200 D. 400

____ What nutrient listed below do plants get primarily from the air?

A. H B. P C. S D. C

____ In plants, the ‘source’ is considered a leaf and the ‘sink’might be a:

A. growing soybean seed B. lower, mature leaf

C. mature root D. photoperiod interval

____ The letter designation of the topsoil horizon is:

A. A B. B C. C D. R

____ The letter designation of a soil horizon found in forest ecosystems but not in

prairie ecosystems is most likely:

A. A B. C C. E D. R

____ Soil parent material formed from rock weathered in place is called:

A. alluvium B. residium

C. lacustrine D. rock till

____ The cation exchange capacity of a soil is a measure of:

A. pH B. soil fertility

C. soil tilth D. soil drainage

____ RuBP carboxylase/oxygenase is:

A. a protein enzyme in photosynthesis B. a protein enzyme in respiration

C. a toxic compound to plant cells D. not found in C4 plants

name___________________________ AGRO 1033, T2, S2007

SHORT ANSWER, LISTING.

1. What distinguishes the agronomic definition of soil from the geologist’s definition?

(2 pts) soil is seen also as a medium for growing crops

2. What can a corn farmer do to improve the photosynthetic capacity of the corn crop to

help increase yields? (5 pts)

many things: Examples: - select high yielding varieties

- plant at proper row width and seeding rate

- fertilize according to soil tests and at the right time

- irrigate if possible

- control foliar damaging insects and disease

3. List below five factors that affect photosynthesis of field crops. (10 pts)

There are many: Examples: - sunlight, photoperiod, leaf area , growth stage,

water, soil nutrients, carbon dioxide, type of crop (C3 or C4), others

4. Complete the unbalanced reactions where indicated: (10 pts)

Photosynthesis

__CO₂__ + __H₂O__ ----------------------------> ____C₆H₁₂O₆____ + O₂

^{sunlight, chloroplasts}

Photorespiration

_H₂O__ + CO₂ -----------------> ___C₆H₁₂O₆____ + __CO₂____ + O₂

^{O2, RuBPcarboxylase/oxygenase}

Respiration

__C₆H₁₂O₆____ + ___O₂____ -----------------> __H₂O___ + CO₂ + __ATP’s_

5. If a farmer has an acid soil that needs to be improved, what should he/she do and

when? (3 pts)

lime, at least 3-6 months ahead of crop

6. What are three benefits of no-till and conservation tillage practices? (6 pts)

Many! Reduce soil erosion, improve water quality, increase water infiltration,

improve soil aggregation, improve soil organic matter

7. What are four of the five factors of soil formation? (8 pts)

1. Parent Material

2. Climate

3. Topography

4. Organisms (both plant and soil)

5. Time!

8. When a crop is irrigated, it is also fertilized. How so? (2 pts)

Trick question here: it supplies the plants with H and O nutrients!

9. Why do C4 crops have a greater potential for dry matter production per acre than C3

crops? (2 pts)

Less carbon losses from photorespiration.

10. List below a plant available form of the nutrients indicated: (5 pts)

N: NH₄⁺, NO₃^-

P: H₂PO₄^-, HPO₄^2-

K: K⁺

Ca: Ca²⁺

11. In planning a soil fertility program for a crop, what is THE MOST important thing to

do? (2 pts)

NO BRAINER ........ SOIL TEST!