module 3

Question 1

The relationship between thermal time (TT) and pasture production (PP) is:

(A) positive and direct: when TT increases, PP also increases;

(B) negative and direct: when TT increases, PP diminishes;

(C) sigmoidal: when TT increases, PP increases quickly at first and then increases more slowly until a maximum plateau is reached;

(D) exponential: with PP increasing exponentially as TT increases;

(E) there is no relationship between TT and PP

Answer 1

(A) positive and direct: when TT increases, PP also increases;

Question 2

Which of the following is involved in stomata opening and closing?

(A) ATP;

(B) potassium and sulphur;

(C) gibberellic acid;

(D) temperatures around 7 ºC;

(E) bud type in fruit tree branches.

Answer 2

(A) ATP;

Question 3

Which of the following nutrients is directly involved in stomata opening?

(A) nitrogen;

(B) potassium;

(C) sulphur;

(D) calcium;

(E) magnesium.

Answer 3

(B) potassium;

Question 4

Nutrients that move within the soil profile are:

(A) nitrogen, sodium, phosphorus;

(B) phosphorus, potassium, calcium;

(C) calcium, magnesium, sodium;

(D) the soil nutrients do not move within the soil profile;

(E) all the soil nutrients move within the soil profile.

Answer 4

(C) calcium, magnesium, sodium;

Question 5

Most studies have shown that erect-leaved crops have a growth advantage over horizontal-leaved plants because of their:

(A) increased light saturation of individual leaves;

(B) greater leaf duration;

(C) greater light penetration into the canopy;

(D) greater photosynthesis of top leaves;

(E) higher canopy extinction coefficient.

Answer 5

(C) greater light penetration into the canopy;

Question 6

. Name three (3) minerals that are both major nutrients and mobile within plants. .…………………., .…………………. and …………………….

Answer 6

nitrogen, potassium and phosphorous

Question 7

.……………….. .………………. .………………. (three words needed) is the surface area of the leaf canopy per unit of ground area, the most important determinant of radiation interception.

Answer 7

leaf area index

Question 8

. If a plant species is able to survive and grow in an acidic soil it is classified as a: .……………… .……………… (2 words).

Answer 8

stress tolerator

Question 9

) Briefly define “vernalisation”

Answer 9

requirement for plants to be exposed to col and or sensitivity to day length allowing plants to regulate development processes

Question 10

Give two (2) endogenous factors that regulate winter dormancy in deciduous trees

Answer 10

abscisic acid (ABA)

gibberellic acid (GA)

Question 11

Water stressed plants close stomata to conserve moisture. This results in:

(A) an increase in transpiration;

(B) a reduction in carbon dioxide absorption;

(C) an increase in photosynthesis as CO2 becomes more concentrated;

(D) an overall rise in plant yield;

(E) fewer, but larger leaves.

Answer 11

(B) a reduction in carbon dioxide absorption;