Which of the following is a plant hormone?

1

(a)

Insulin

(b)

Thyroxin

(c)

Oestrogen

(d)

Cytokinin

The brain is responsible for

1

(a)

Thinking

(b)

balancing the body

(c)

regulating

(d)

All of the above

Which is the correct sequence of the components of a reflex arc?

1

(a)

Receptors \(\rightarrow\) Muscles \(\rightarrow\) Sensory ​​​​​​neuron \(\rightarrow\) Motor neuron \(\rightarrow\) Spinal cord

(b)

Receptors \(\rightarrow\) Motor neuron \(\rightarrow\) Spinal cord \(\rightarrow\) Sensory ​​​​​​neuron \(\rightarrow\)Muscle

(c)

Receptors \(\rightarrow\) Spinal cord \(\rightarrow\) Sensory ​​​​​​neuron \(\rightarrow\) Motor neuron \(\rightarrow\) Muscle

(d)

Receptors \(\rightarrow\) Sensory ​​​​​​neuron \(\rightarrow\) Spinal cord \(\rightarrow\) Motor neuron \(\rightarrow\) Muscle

Which of the following statements are true about the brain?
(i) The main thinking part of brain is hind brain
(ii) Centres of hearing, smell, memory, sight, etc. are located in forebrain.
(iii) Involuntary actions like salivation, vomiting, blood pressure are controlled by the medulla in the hind brain
(iv) Cerebellum does not control posture and balance of the body

1

(a)

(i) and (ii)

(b)

(i), (ii) and (iii)

(c)

(ii) and (iii)

(d)

(iii) and (iv)

The movement of shoot towards light is

1

(a)

Geotropism

(b)

Hydrotropism

(c)

Chemotropism

(d)

Phototropism

The main function of abscisic acid in plants is to

1

(a)

Increase the length of cells

(b)

Promote cell division

(c)

Inhibit growth

(d)

Promote growth of stem

Which of the following is not associated with growth of plant?

1

(a)

Auxin

(b)

Gibberellins

(c)

Cytokinins

(d)

Abscissic acid

Iodine is necessary for the synthesis of which hormone?

1

(a)

Adrenaline

(b)

Thyroxin

(c)

Auxin

(d)

Insulin

The shape of guard cells change due to change in the

1

(a)

Protein composition of cells

(b)

Temperature of cells

(c)

Amount of water in cells

(d)

Position of nucleus in the cells

The movement of sunflower in accordance with the path of sun is due to

1

(a)

Phototropism

(b)

Geotropism

(c)

Chemotropism

(d)

Hydrotropism

The substance that triggers the fall of mature leaves and fruits from plants is due to

1

(a)

Auxin

(b)

Gibberellin

(c)

Abscissic acid

(d)

Cytokinin

What are plant hormones?

2

(a)

How do auxins promote the growth of a tendril around a support?

2

(a)

How does our body respond when adrenaline is secreted into the blood?

2

(a)

Which signal will get disrupted in case of a spinal cord injury?

2

(a)

What is the difference between the manner in which movement takes place in a sensitive plant and the movement in our legs?

2

(a)

What is photoperiodism?

2

(a)

What constitutes the central and peripheral nervous systems? How are the components of central nervous system protected?

5

(a)

What are reflex action? Give two examples. Explain a reflex arc.

5

(a)

"Nervous and hormonal system together perform the function of control and coordination in human beings." Justify the statement.

5

(a)

How does chemical coordination take place in animals?

5

(a)

Why is the flow of signals in a synapse from axonal end of one neuron to dendritic end of another neuron but not the reverse?

5

(a)