Sigmoid Growth Curve

Q. Typical growth curve in plants is:

1. Parabolic
2. Sigmoid
3. Linear
4. Stair -steps shaped

Q.

Sigmoid curve showing the three distinct phases of growth follows the sequence of

1. Steady state, log phase and lag phase

2. Lag phase, log phase and steady phase

3. Log phase, lag phase and steady phase

4. Log phase, steady phase and lag phase

Q. A typical growth curve in plants is

1. linear
2. parabolic
3. sigmoid
4. zig-zag shaped

Q. Based on cellular mechanisms there are two major types of regeneration found in the animals. Which one of the the following is the correct example of the type mentioned?

(A) Morphallaxis	Regeneration of two transversely cut equal pieces of a Hydra into two small Hydra.
(B) Epimorphosis	Replacement of old and dead erythrocytes by the new ones.
(C) Morphallaxis	Healing up of a wound in the skin.
(D) Epimorphosis	Regeneration of crushed and filtered out pieces of a Planaria into as many new planarians.

1. (C)Morphallaxis- Healing up of a wound in the skin.
2. (B)Epimorphosis- Replacement of old and dead erythrocytes by the new ones.
3. (A)Morphallaxis- Regeneration of two transversely cut equal pieces of a Hydra into two small Hydra.
4. (D)Epimorphosis- Regeneration of crushed and filtered out pieces of a Planaria into as many new planarians.

Q.

Identify A, B, and C in the given graph

1. A - lag phase, B - log phase, C -Stationary phase

2. A - slow phase, B - sigmoid phase, C- stationary phase

3. A - log phase, B - lag phase , C -Stationary phase

4. A-log phase, B - exponential phase, C-lag phase

Q. Assertion :- A sigmoid curve is characteristic of plants growing in a natural environment.
Reason:- In natural conditions the supply of nutrients and food is ever increasing.

1. Both assertion and reason are true and reason is the correct explanation of assertion.
2. Both assertion and reason are true but reason is not the correct explanation of assertion.
3. The assertion is true but reason is false.
4. Both assertion and reason are false.

Q. Which of the following growth curves is a characteristic of most of the plants in their natural environment?

1. Arithmetic
2. Parabolic
3. Sigmoid
4. Linear

Q.

Question 23:

In the figure of sigmoid growth curve given below, label segments 1, 2 and 3.

Q. The embryo sac of an Angiosperm is made up of

1. 8 cells
2. 7 cells and 8 nuclei
3. 8 nuclei
4. 7 cells and 7 nuclei

Q. ________ curve is obtained for cells in culture.

1. J-shaped
2. Linear
3. V-shaped
4. S-shaped

Q.

Growth plotted against time give a

1. Parabolic curve

2. Sigmoid curve

3. Upright line

4. Horizontal line

Q.

Given below is a graph drawn on the parameters of growth versus time. A, B and C respectively represent

1. Lag phase, log phase and steady state phase

2. Exponential phase, log phase and steady state phase

3. Steady state phase, lag phase and log phase

4. Slow growing phase, lag phase and steady state phase

5. Lag phase, steady state phase and log phase

Q.

In sigmoid growth curve, growth is slow in:

1. Stationary phase

2. Log phase

3. Exponential phase

4. Lag phase

Q.

Maximum growth rate occurs in the

1. Senescent phase

2. Stationary phase

3. Lag phase

4. Exponential phase

Q. Recognise the figure and find out the correct matching.

1. b—egg nucleus, d—vegetative nucleus, a—synergid, f—filiform apparatus, e—male gametes, c— central cell.
2. b—egg nucleus, e—vegetative nucleus, c—synergid, d—filiform apparatus, f—male gametes, a— central cell
3. b—egg nucleus, f—vegetative nucleus, c—synergid, d—filiform apparatus, e—male gametes, a—central cell
4. a—egg nucleus, f—vegetative nucleus, b—synergid, e—filiform apparatus, d—male gametes, c—central cell

Q. Given below is a graph showing the growth of yeast. This is the type of growth curve noted in most organisms. What does the segment C-D indicate?

1. No new individuals are formed.
2. Death rate is zero.
3. The rate of formation and rate of death of individuals is the same.
4. The experiment stopped.

Q. Assertion :In most biological systems, the initial growth is slow (lag phase). Reason: With limited nutrient supply, the growth slows down, leading to a stationary phase.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q.

Which is the correct sequence for different phases of growth ?

1. Cell division – cell elongation – cell differentiation

2. Cell formation of cell different – cell elongation

3. Cell differentiation – cell formation – cell elongation

4. Cell differentiation – cell elongation – cell formation

Q. What kind of a curve can you expect in a tree showing seasonal activities?

Q.

A plant cell has potential to develop into full plant. This
property of the plant cell is called.

1. a) tissue culture

2. b. totipotency.

3. c) pleuripotency

4. d) gene cloning

Q.

Write the number of chromosomes present in the human body.

Q. Typical growth curve in plants is

1. Parabolic
2. Linear
3. Sigmoid
4. Stair-steps shaped

Q. Which of the following growth curves is a characteristic of most of the plants in their natural environment?

1. Arithmetic
2. Sigmoid
3. Linear
4. Parabolic

Q.

How many pairs of chromosomes are found in human body cells-23, 46, 16?

Q. A population of any species in nature follows:

1. Linear growth
2. Exponential growth
3. Logistic growth
4. Stable growth

Q. A growing shoot apex follows a helical path and this phenomenon corresponds to

1. diurnal growth rhythm
2. allometric growth
3. a biological clock
4. circumnutation

Q.

Given below is a graph drawn on the parameters of growth versus time. A, B and C respectively represent

1. Exponential phase, log phase and steady state phase

2. Steady state phase, lag phase and log phase

3. Slow growing phase, lag phase and steady state phase

4. Lag phase, steady state phase and log phase

5. Lag phase, log phase and steady state phase

Q.

Is Yeast cell size constant?

Q. What is sigmoid growth curve? Why is it so called?

Q. What is growth curve?