Tag: zoology

Questions Related to zoology

If a man could learn to stop his heartbeat at will, he must have control over his 

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Central nervous system

  2. Peripheral nervous system

  3. Autonomic nervous system

  4. Cranial nerves

Show answer
Correct Option: C
Explanation:

The central nervous system includes brain and spinal cord. It integrates and stores the sensory information from external and internal sense organs and commands different organs to respond accordingly.

Peripheral nervous system lies outside the central nervous system. It serves to carry the sensory information from external sensory receptors to CNS and motor signals from CNS to skeletal muscles via its somatic division (the voluntary actions). The autonomic division of peripheral nervous system controls the cardiac and smooth muscles and glands, thereby the functioning of internal organs, without our conscious control (the involuntary actions). The autonomic nervous system controls the heartbeat rate via cardioregulatory centre in the medulla oblongata. The emergency conditions activate the sympathetic motor nerve and make the adrenal medulla release epinephrine and norepinephrine which in turn increase the heartbeat rate. On the other hand, vagus nerve conducts the parasympathetic motor impulses which in turn slow down the heartbeat rate by the effect of acetylcholine. Thus, to control heartbeat, a man should have control over its autonomic nervous system. 
The 12 pairs of cranial nerves are part of the peripheral nervous system and are mostly concentrated in head, neck and facial region of the body (vagus nerve X being the part of autonomous division serves as an exception). 
Hence, the correct answer is option C.

The heart rate is increased by a nerve which belongs to the following division of nervous system.
I. Autonomic
II. Central
III. Peripheral
IV. Sympathetic

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. I and IV only

  2. II and III only

  3. I, II, and III

  4. I, III, and IV

  5. II, III, and IV

Show answer
Correct Option: A
Explanation:

The autonomous nervous system controls the heart beat rate via cardioregulatory centre in the medulla oblongata. The emergency conditions activate the sympathetic motor nerve and make the adrenal medulla release epinephrine and norepinephrine which in turn increase the heart beat rate. Hence, the nerve which increases heart beat is part of autonomic and sympathetic nervous system. The central nervous system includes brain and spinal cord only. The peripheral nervous system includes all cranial and spinal nerves; the 12 pairs of cranial nerves, except Vagus nerve, are part of the peripheral nervous system and are mostly concentrated in head, neck and facial region of the body. Vagus nerve conducts the parasympathetic motor impulses which in turn slow down the heart beat rate by the effect of acetylcholine; a neurotransmitter released by the parasympathetic nervous system. 

Therefore, the correct answer is option A.

Which of the following is not a characteristic of the human sympathetic nervous system?

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Prepares the person for fight or flight

  2. Has ganglia near the spinal cord

  3. Increases heart beat

  4. Is a craniosacral division of the autonomic nervous system

Show answer
Correct Option: D
Explanation:

The human sympathetic nervous system controls the functions (for example accelerated heartbeat, reduced digestion rate etc) that help prepare the organism for the physical strain which is required to escape from a dangerous situation.

The preganglionic fibres of sympathetic nervous system arise from thoracic lumbar portion of spinal cord and immediately terminate in ganglia lying near the cord. 
Under stress conditions, preganglionic neurons of this system release acetylcholine which in turn makes postganglionic neurons to release norepinephrine causing increased heart beat.
Sympathetic nervous system is thoracic lumber division of autonomous nervous system. The parasympathetic system is its sacral division
So, the correct answer is 'Is a craniosacral division of the autonomic nervous system'

Which of the following systems slows the heart rate, constricts the pupil and stimulates pancreatic activity during emergency conditions?

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Enteric nervous system

  2. Somatic nervous system

  3. Peripheral nervous system

  4. Parasympathetic division

  5. Sympathetic division

Show answer
Correct Option: D
Explanation:
Parasympathetic nervous system slows the heart rate, constricts the pupil and stimulates pancreatic activity during emergency conditions.
The parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions.
Heart rate is controlled by the two branches of the autonomic nervous system. The sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS). The sympathetic nervous system (SNS) releases the hormones (catecholamines - epinephrine and norepinephrine) to accelerate the heart rate. The parasympathetic nervous system (PNS) releases the hormone acetylcholine to slow the heart rate. 
The reduced heart rate results from an increase in activity of the parasympathetic nervous system, and perhaps from a decrease in activity of the sympathetic nervous system.
Examples of body functions stimulated by the parasympathetic nervous system  include sexual arousal, salivation, lacrimation, urination, digestion, and defecation. 
The parasympathetic nervous system is also known as the rest and digest activation, is the segment that assists with normal, autonomic functions. Typically all are in the control of the parasympathetic nervous system. Since this is the normal state of the body, the parasympathetic system is more active than the sympathetic system in controlling body functions.

Which of the following human parasympathetic function is not under the control of a cranial nerve?

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Contraction of bladder

  2. Constriction of pupil

  3. Increase of salivation

  4. Stimulation of gall bladder activity

Show answer
Correct Option: A
Explanation:

The parasympathetic nervous system decreases respiration and heart rate and increases digestion. Stimulation of the parasympathetic nervous systems results in the construction of pupils. Salivation, decrease heart rate and blood pressure.

So, the correct option is 'Contraction of bladder'.

Which of the following is not an effect produced by parasympathetic stimulation?

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Dilation of the pupils

  2. Increased saliva production

  3. Increased stomach activity

  4. Constriction of the bronchi

Show answer
Correct Option: A
Explanation:

The parasympathetic nervous system decreases respiration and heart rate and increases digestion. Stimulation of the parasympathetic nervous systems results in the construction of pupils. Decrease heart rate and blood pressure.

So, the correct option is 'Dilation of pupil'.

How many pairs of sympathetic ganglia are present in ANS?

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. 10

  2. 12

  3. 22

  4. 31.

Show answer
Correct Option: C
Explanation:

Sympathetic ganglia are the ganglia of the sympathetic nervous system. It's function is to deliver information to the body about stress and when the body is in danger, and are responsible for the fight-or-flight response. There are usually 21-23 pairs of these ganglia are present that is, 3 in the cervical region, 11 in the thoracic region, 4 in the lumbar region and 4-5 in the sacral region. So, the correct answer is option C.

An example of autonomous nervous system is

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Swallowing food

  2. Pillary reflex

  3. Peristalsis of intestine

  4. Knee-jerk response

Show answer
Correct Option: C
Explanation:

The autonomic nervous system controls the coordinated and involuntary movements of the body. The peristalsis of the intestine is an involuntary visceral movement which is controlled by the autonomic nervous system. 

A. Swallowing of food initially is controlled by the somatic nervous system.
B. Pupillary reflex is an unconditioned reflex.
C. Peristalsis of the intestine is controlled by the autonomic nervous system.
D. The knee-jerk response is a monosynaptic reflex action.
Hence, the correct answer is 'Peristalsis of intestine'.

The parasympathetic division of the autonomic nervous system:

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. arises from the cranial and sacral spinal cord segments

  2. is concerned with conserving and restoring energy H

  3. has ganglia near or within visceral effectors

  4. all of the above

Show answer
Correct Option: D
Explanation:

The parasympathetic division of autonomic nervous system. The nerve fibres of this system arise from the brain, the cranial nerves and the sacrum of the spinal cord, the sacral nerves

The parasympathetic system is also called the rest and digest system as it stimulates digestion and assimilation
The efferent nerves of the parasympathetic nervous system form ganglia close to the visceral organs or the nerves are innervated in the visceral organs, resulting in the nerve fibers closer to the effector organs to be very short in length
So, the correct option is 'all of the above'

Birds, bees and bacteria are able to navigate their path with the help of

zoology nervous system nervous systems involved in emotions types of nervous system components of nervous system

  1. Brain

  2. Hormones

  3. Intuition

  4. Magnetite

Show answer
Correct Option: D