Tag: life processes: control and coordination

Questions Related to life processes: control and coordination

Blood sugar level is an example of _______

  1. Positive feed back mechanism

  2. Negative feedback mechanism

  3. Both A and B

  4. None of these


Correct Option: B
Explanation:

The body has a mechanism to maintain a normal state. Whenever there is change in thus state there are messages through the body systems to increase if there is a fall below the normal , or decrease if there is rise above the normal. This kind of ordering for the opposite. Is negative feedback to restore the normal state.

Hormonal secretions are controlled by

  1. Feedback mechanism

  2. Autosomal disorder

  3. Genetic disorder

  4. None


Correct Option: A
Explanation:

'Too much, slow down or too little, speed up' -this is the feedback mechanism. the body has a mechanism to maintain a normal state. Whenever there is a change in this state there are messages through the body systems to increase if there is a fall below the normal, or decrease if there is rise above the normal.  This kind of ordering for the opposite Is negative feedback to restore the normal state. examples of positive feedback mechanisms are very few. One example is that of uterine contractions during childbirth. The normal state of the uterus is uncontracted, one contraction instead of commanding to come to normal gives a message to continue further (positive feedback till the delivery is completed).

So, the correct answer is 'Feedback mechanism'.

Uterine contraction during child birth is an example of ______

  1. Positive feed back mechanism

  2. Negative feedback mechanism

  3. Both A and B

  4. None of these


Correct Option: A
Explanation:

Examples of positive feed back mechanisms are very few. One example is that of uterine contractions during child birth. Normal state of uterus is un contacted, one contraction instead of commanding to come to normal gives a message to continue further (positive feedback till the delivery is completed).

'Too much, slow down or too little, speed up' this is the of

  1. Feedback mechanism

  2. Autosomal disorder

  3. Genetic disorder

  4. None


Correct Option: A
Explanation:

'Too much, slow down or too little, speed up' -this is the feedback mechanism. the body has a mechanism to maintain a normal state. Whenever there is a change in this state there are messages through the body systems to increase if there is a fall below the normal, or decrease, if there is a rise above the normal. This kind of ordering for the opposite Is negative feedback to restore the normal state.

So, the correct answer is 'Feedback mechanism'.

Feedback mechanisms can be

  1. Positive

  2. Negative

  3. Both

  4. None


Correct Option: C
Explanation:

'Too much, slow down or too little, speed up' -this is the feedback mechanism. the body has a mechanism to maintain a normal state. Whenever there is a change in this state there are messages through the body systems to increase if there is a fall below the normal, or decrease if there is rise above the normal.  This kind of ordering for the opposite Is negative feedback to restore the normal state. examples of positive feedback mechanisms are very few. One example is that of uterine contractions during childbirth. The normal state of the uterus is uncontracted, one contraction instead of commanding to come to normal gives a message to continue further (positive feedback till the delivery is completed).

So, the correct answer is 'Both'.

The brain is responsible for

  1. Thinking

  2. Regulating the heart beat

  3. Balancing the body

  4. All of the above


Correct Option: D
Explanation:

The cerebellum is the convoluted subdivision of brain stem and is associated with coordination of muscular movement, muscle tone and balance. Medulla oblongata controls consciousness and arousal (the reticular formation) and its cardiovascular reflex centre controls heartbeat. The cerebrum is the largest and uppermost division of brain. It is the centre for higher thought processes required for learning, memory, language and speech. The correct answer is D.

Select the correct option:

Blood-brain barrier in adults has ........... junctions between cells.

  1. Tight

  2. Adhering

  3. Gap

  4. None of these


Correct Option: A
Explanation:

The blood-brain barrier is a dynamic conduit for transport taking place between brain and blood. The blood vessels and brain are lined with endothelial cells that are wedged tightly together, creating a nearly impermeable boundary.

the blood-brain barrier helps block harmful substances from entering the brain.
So the correct option is 'Tight'.

Assertion: In man, only peripheral nervous system is present.

Reason: The peripheral nervous system includes nerves coursing between the central nervous system and different parts of the body.

  1. If both the assertion and the reason are true and the reason is the correct explanation of the assertion

  2. If both the assertion and the reason are true and the reason is not the correct explanation of the assertion

  3. If the assertion is true and the reason is false

  4. If both the assertion and the reason is false

  5. If the assertion is false but the reason is true


Correct Option: E
Explanation:

The nervous system of human comprises of Central Nervous System - comprises of brain and spinal cord. Peripheral Nervous System - comprises of nerves present between brain and body parts.

Endorphin release is stimulated by

  1. Sleep

  2. Endogenous rhythm

  3. Exercise

  4. Carotene-rich food


Correct Option: C
Explanation:
Endomorphins are the chemical substance which is present in the neurons. It helps in the perception of pain, reactions to stress, and cardiovascular, respiratory and digestive functions. They are produced within the body so they are known as endogenous. They specifically work by binding to opoid receptors which are mainly found in nervous system and regulates the motor neurons which helps to coordinate the physical activity.
So, the correct answer is option C.

The human brain weight approximately ..........% of the body weight.

  1. 1%

  2. 2%

  3. 5%

  4. 10%


Correct Option: B
Explanation:
The adult human brain weighs about 3 pounds (1,300-1,400 g). The adult human brain is about 2 % of the total body weight. The average human brain is 140 mm wide.
So, the correct answer is 2%.