a(i) Lag phases; Dry mass increases slowly; became in plant has not developed
leaves; for photosynthesis hence is depending on stored food;
(ii) Expontial phase; Rapid growth /increase in dry mass, leaves developed; photosynthesis taking place leading to accumulation of food and rapid cell division / plant adapted to the environment
(iii) Death phase/ senescence; Negative growth/decrease in dry mass as some tissues die after reaching maximum maturity; Fall in photosynthesis activity; toxic wastes poison tissues;
(b)
(i) When dry mass was first recorded/at germination
(ii) Dry mass would decrease first because food is oxidized to produces energy; water and carbon dioxide/utilized in respiration;
(c)
(i) Harvest every week about five seedlings; dry in oven to a constant dry mass; Calculate the average mass for one seedling and record the results.
(ii) Advantage; Dry mass is not affected by environmental conditions while fresh weight is dependent on the amount of water in the plant which fluctuate with environmental factors affecting transpiration rate
marto answered the question on October 7, 2019 at 09:30
-
The experiment set – up below was designed to investigate an aspect of germination.
(Solved)
The experiment set – up below was designed to investigate an aspect of germination.
a) Why was potassium hydroxide pellets used in this experiment?
b) What was the role of moist cotton wool in this experiment?
c) i) By means of an arrow, indicate on the diagram the direction in which red dye would move
during the experiment.
ii) Give reason for your answer in c(i) above.
d) Other than the factor investigated above, state any other one factor necessary for germination
process.
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents a stage during the process of germination.
(Solved)
The diagram below represents a stage during the process of germination.
(a) (i) Name the type of germination illustrated in the diagram
(ii) Give a reason for your answer in (a) (i) above.
(b) Give two functions of the part labelled X
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents a growth pattern of arthropods.
(Solved)
The diagram below represents a growth pattern of arthropods.
(a) Name the type of growth pattern represented on the graph.
(b)Identify the process represented by X.
(c) Which hormone is responsible for process at X in (b) above?
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents female reproductive system.
(Solved)
The diagram below represents female reproductive system.
a) Name the part labeled; A, B, C and D
b) State two functions of structure A
c) How is part C adapted to its function?
d) Of what significance is part E to reproduction?
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents some hormones, their sources and functions in mammals.
(Solved)
The diagram below represents some hormones, their sources and functions in mammals.
a) Name the hormones I, II and III
b) Name hormones IV and state its function
c) Name the control labelled A & B
d) Name one secondary sexual characteristic common to both males and females
Date posted:
October 7, 2019
.
Answers (1)
-
The diagrams below represent two gynoecia A and B obtained from two different plants.
(Solved)
The diagrams below represent two gynoecia A and B obtained from two different plants.
(a) What name is given to;
Gynoecium A?
Gynoecium B?
(b) State the observable difference between the gnoecia A and B
(c) State the role played by Heterostyly in plants.
Date posted:
October 7, 2019
.
Answers (1)
-
Describe the possible effects of discharging hot effluent from a factory into a slow flowing river.
(Solved)
Describe the possible effects of discharging hot effluent from a factory into a slow flowing river.
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below illustrate a process in a given species of organism.
(Solved)
The diagram below illustrate a process in a given species of organism.
a) Name the organism that undergoes the process above.
b) Identify the process shown to be taking place.
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below shows a pollen – tube entering the ovule of a flowering plant.
(Solved)
The diagram below shows a pollen – tube entering the ovule of a flowering plant.
a) Name the parts labeled A, B and D
b) Name the kind of fertilization exhibited by the above flowering plant.
Date posted:
October 7, 2019
.
Answers (1)
-
State three ways in which flowers parent self pollination.
(Solved)
State three ways in which flowers parent self pollination.
Date posted:
October 7, 2019
.
Answers (1)
-
Name the hormone that Stimulates the disintegration of the corpus inteum when fertilization fails to take place.
(Solved)
Name the hormone that Stimulates the disintegration of the corpus inteum when fertilization fails to take place.
Date posted:
October 7, 2019
.
Answers (1)
-
Explain why hormone testosterone still exerts its influence even when vas deferens have been cut.
(Solved)
Explain why hormone testosterone still exerts its influence even when vas deferens have been cut.
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below shows a phenomenon which occurs during cell division.
(Solved)
The diagram below shows a phenomenon which occurs during cell division.
(a) Name the part labeled T.
(b) (i) State the biological importance of the part labelled T.
(ii) Identify the type of cell division in which this phenomenon occurs
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents a mammalian nephron.
(Solved)
The diagram below represents a mammalian nephron.
(a) Name the structures labeled B,C and D
(c) Name the process by which substances are reabsorbed from structure C into blood capillaries
(d) How is the pressure in structure A achieved?
Date posted:
October 7, 2019
.
Answers (1)
-
Describe the path taken by urea from the organ where it is formed until it is released from the human body.
(Solved)
Describe the path taken by urea from the organ where it is formed until it is released from the human body.
Date posted:
October 7, 2019
.
Answers (1)
-
An experiment was carried out to determine the effect of drinking on excess amount of water on the flow of urine. A person drinks one...
(Solved)
An experiment was carried out to determine the effect of drinking on excess amount of water on the flow of urine. A person drinks one litre of water and urine was collected at intervals of 15 minutes.
The results were as shown below.
(a) Plot a suitable graph to represent urine output with time.
(b) Explain the rate of flow of urine between the following times;
(i) 15 and 60 minutes.
(ii) 60 and 75 minutes.
(iii) 75 and 135 minutes.
(c) Name two hormones responsible for regulation of relative amount of salts and water in man.
Date posted:
October 7, 2019
.
Answers (1)
-
The diagram below represents a mammalian nephron.
(Solved)
The diagram below represents a mammalian nephron.
(i) Name the structure labelled Q
(ii) State two adaptations of part labeled R
Date posted:
October 4, 2019
.
Answers (1)
-
The apparatus below was used to investigate anaerobic respiration:-
(Solved)
The apparatus below was used to investigate anaerobic respiration:-
a) How would you remove dissolved oxygen from the glucose before the experiment commencing?
(b) State what happens to the lime water as the experiment proceeds to the end
(c) Describe the reactions in the experiment
(d) Explain what would happen if the temperature of glucose solution and yeast was raised beyond 45 degrees C?
Date posted:
October 4, 2019
.
Answers (1)
-
How does the sunkness of stomata help in minimizing the rate of transpiration in plants?
(Solved)
How does the sunkness of stomata help in minimizing the rate of transpiration in plants?
Date posted:
October 4, 2019
.
Answers (1)
-
The apparatus below was set up by a student to find out the changes in gases during germination.
(Solved)
The apparatus below was set up by a student to find out the changes in gases during germination.
a) After 48 hours the level of water in the U-tube at A and B was as shown. Explain the
observation
b) Calculate the respiration quotient (RQ) from the equation below
c) Identify the substrate being respired in the above equation
Date posted:
October 4, 2019
.
Answers (1)