1)
Which of the following is a plant hormone?
Which of the following is a plant hormone?
(a)
Insulin
Insulin
(b)
Thyroxin
Thyroxin
(c)
Oestrogen
Oestrogen
(d)
Cytokinin
Cytokinin
ANSWER:
– Cytokinin
– Cytokinin
2)
The gap between two neurons is called a
The gap between two neurons is called a
(a)
dendrite.
dendrite.
(b)
synapse.
synapse.
(c)
axon.
axon.
(d)
impulse.
impulse.
ANSWER:-Synapse.
3)
The brain is responsible for
The brain is responsible for
(a)
thinking.
thinking.
(b)
regulating the heart beat.
regulating the heart beat.
(c)
balancing the body.
balancing the body.
(d)
all of the above.
all of the above.
ANSWER:-
all of the above.
all of the above.
4)
What is the function of receptors in our body?
What is the function of receptors in our body?
Think
of situations where receptors do not work properly. What problems are likely to
arise?
of situations where receptors do not work properly. What problems are likely to
arise?
ANSWER:-
Receptors are sensory structures (organs/tissues or cells) present all over the
body.
Receptors are sensory structures (organs/tissues or cells) present all over the
body.
When
the receptors are damaged, the external stimuli transferring signals to the
brain cannot be felt.
the receptors are damaged, the external stimuli transferring signals to the
brain cannot be felt.
5)
Draw the structure of a neuron and explain its function.
Draw the structure of a neuron and explain its function.
ANSWER:-
Functions
of the three parts of a neuron:
of the three parts of a neuron:
Axon:
It conducts messages away from the cell body.
It conducts messages away from the cell body.
Dendrite:
It receives information from axon of another cell and conducts the messages
towards the cell body.
It receives information from axon of another cell and conducts the messages
towards the cell body.
Cell
body: It contains nucleus, mitochondria, and other organelles. It is mainly
concerned with the maintenance and growth.
body: It contains nucleus, mitochondria, and other organelles. It is mainly
concerned with the maintenance and growth.
6)
How does phototropism occur in plants?
How does phototropism occur in plants?
ANSWER:-Environmental
triggers such as light will change the directions that plant parts grow in.
These directional, or tropic, movements can be either towards the stimulus, or
away from it. So, in two different kinds of phototropic movement, shoots
respond by bending towards light while roots respond by bending away from it.
triggers such as light will change the directions that plant parts grow in.
These directional, or tropic, movements can be either towards the stimulus, or
away from it. So, in two different kinds of phototropic movement, shoots
respond by bending towards light while roots respond by bending away from it.
7)
Which signals will get disrupted in case of a spinal cord injury?
Which signals will get disrupted in case of a spinal cord injury?
ANSWER:-In
case of the spinal cord injury, the signals coming from the nerves as well as
the signals coming to the receptors will be disrupted.
case of the spinal cord injury, the signals coming from the nerves as well as
the signals coming to the receptors will be disrupted.
8)
How does chemical coordination occur in plants?
How does chemical coordination occur in plants?
ANSWER:-
Plants respond to stimuli by showing movements. The growth, development, and
responses to the environment in plants is controlled and coordinated by a
special class of chemical substances known as hormones. These hormones are
produced in one part of the plant body and are translocated to other needy
parts.
Plants respond to stimuli by showing movements. The growth, development, and
responses to the environment in plants is controlled and coordinated by a
special class of chemical substances known as hormones. These hormones are
produced in one part of the plant body and are translocated to other needy
parts.
9)
What is the need for a system of control and coordination in an organism?
What is the need for a system of control and coordination in an organism?
ANSWER:-All
the movements that occur in response to stimuli are carefully coordinated and
controlled. In animals, the control and coordination movements are provided by
nervous and muscular systems. The nervous system sends messages to and away
from the brain. The spinal cord plays an important
role in the relay of messages. In the absence of this system of
control and coordination, our body will not be able to function properly.
the movements that occur in response to stimuli are carefully coordinated and
controlled. In animals, the control and coordination movements are provided by
nervous and muscular systems. The nervous system sends messages to and away
from the brain. The spinal cord plays an important
role in the relay of messages. In the absence of this system of
control and coordination, our body will not be able to function properly.
10)
How are involuntary actions and reflex actions different from each other?
How are involuntary actions and reflex actions different from each other?
ANSWER:-Involuntary
actions cannot be consciously controlled. On the other hand,
the reflex
actions such as closing of eyes immediately when bright light is focused show
sudden response and do not involve any thinking. This means that unlike
involuntary actions, the reflex actions are not under the control of brain.
actions cannot be consciously controlled. On the other hand,
the reflex
actions such as closing of eyes immediately when bright light is focused show
sudden response and do not involve any thinking. This means that unlike
involuntary actions, the reflex actions are not under the control of brain.
11)
Compare and contrast nervous and hormonal mechanisms for control and
coordination in animals.
Compare and contrast nervous and hormonal mechanisms for control and
coordination in animals.
ANSWER:-
Ans:
|
Nervous control
|
Hormonal Control
|
||
|
1
|
It is consist of nerve impulses between PNS, CNS and Brain.
|
1
|
It consists of endocrine system which secretes hormones
directly into blood. |
|
2
|
Here response time is very short.
|
2
|
Here response time is very long.
|
|
3
|
Nerve impulses are not specific in their action.
|
3
|
Each hormone has specific actions.
|
|
4
|
The flow of information is rapid.
|
4
|
The flow of information is very slow.
|
12)
What is the difference between the manner in which movement takes place in a
sensitive plant and the movement in our legs?
What is the difference between the manner in which movement takes place in a
sensitive plant and the movement in our legs?
ANSWER:-
Ans:
|
Movement in sensitive plants
|
Movement in our legs
|
||
|
1
|
The movement in a sensitive plant is a response to
stimulus(touch) which is a involuntary action. |
1
|
Movement in our legs is a voluntary action.
|
|
2
|
No special tissue is there for the transfer of information
|
2
|
A complete system CNS and PNS is there for the information
exchange. |
|
3
|
Plant cells do not have specialised protein for movements.
|
3
|
Animal cells have specialised protein which help muscles to
contract. |