Tag: control and coordination in living organisms

Questions Related to control and coordination in living organisms

Medulla oblongata controls involuntary functions.
zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Medulla oblongata is the part of hindbrain. It is located in the brainstem, anterior to the cerebellum. It controls the involuntary functions . It is linked to the autonomic system and has cardiac, respiratory, vomiting and vasomotor centres. It also controls breathing heart rate and blood pressure.

All movements in response to the environment can be carefully controlled.

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Each kind of a change in the environment evokes an appropriate movement in response. When we want to talk to our friends in class, we whisper, rather than shouting loudly. So, the movement to be made depends on the event triggering it. Hence, such controlled movement must be connected to the recognition of various events in the environment, followed by only the correct movement in response. Therefore, the correct answer is option A.

Which of the following statements are true about reflex action?
i. It is a response activated after the activity or incident completes.
ii. It is an involuntary action.
iii. It is the sudden action in response to something in the environment.
iv. Impulse is carried to the brain directly for the response.

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. (ii) and (iii)

  2. (ii) and (iv)

  3. Both A and B

  4. None of the above

Show answer
Correct Option: A
Explanation:

Reflex action is an action which is given in response to something in the environment. It is an immediate action taken without much thinking and it does not have our control. The spinal cord is responsible for the response of the body because the impulse has not reached the brain till then. Therefore, the correct answer is option A.

State which of the following incidents are involuntary in nature.
 

i.   Rehan running in a 100-meter race.
 ii.  Preeti sneezing due to cold.
 iii. Rahul pricked his finger by the needle while sewing his shirt.

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. All of the above

  2. (i) and (iii)

  3. (i) and (ii)

  4. (ii) and (iii)

Show answer
Correct Option: D
Explanation:

  • Voluntary actions are those which can be controlled by us like clapping, dancing, jumping, running, etc. 
  • Whereas, involuntary actions are those which cannot be regulated or stopped by us like the circulation of blood, heartbeat, etc. Hence, reflex actions are involuntary actions that are done to save oneself from danger. 

Therefore, the correct answer is option D.


Closing both the eyes when a torch light is flashed on one eye is a part of 
zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. Reflex action

  2. Chemotropism

  3. Hormonal control

  4. None of these

Show answer
Correct Option: A
Explanation:

  • The best-known reflex is the pupillary light reflex. If a light is flashed near one eye, the pupils of both eyes contract.
  •  Light is the stimulus, impulses reach the brain via the optic nerve, and the response is conveyed to the pupillary musculature by autonomic nerves. 

Therefore, the correct answer is option A.

Which is not a reflex action?

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. Swallowing of food

  2. Shivering in cold

  3. Salivation at choicest food

  4. Closure of eyes lids by flashing light

Show answer
Correct Option: A

Ivan Pavlov performed experiments on

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. Simple reflexes

  2. Conditioned reflexes

  3. Cardiac reflexes

  4. Origin of life

Show answer
Correct Option: B

Reflex action is

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. Stimulus Sensory Motor Response

  2. Stimulus Motor Sensory Response

  3. Receptor Motor Sensory Response

  4. Sensory Stimulus Motor Response

Show answer
Correct Option: A

Which of the following is not an involuntary action?

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. Vomiting

  2. Salivation

  3. Heart beat

  4. Chewing

Show answer
Correct Option: D
Explanation:

Involuntary actions are the actions which are happening without the conscious choice of an organism. The examples for involuntary actions are: Vomiting, yawning, salivation, heart beats, coughing, sneezing, etc.  Whereas chewing is a voluntary action, which is controllable.

Which of the following actions are reflex actions?


1.Movement of the diaphragm during respiration
2.Coughing
3.Yawning
4.Sneezing
5.Removal of hand on being touched by hot object

zoology control and coordination in living organisms the reflex action reflex action and reflex arc basic reflex action and reflex arc

  1. A. II and v only

  2. B. III,IV and V only

  3. C. IV and V only

  4. D. I,II,III,IV and V

Show answer
Correct Option: A
Explanation:

Reflex action is an involuntary action and it is a sudden reaction against the stimulus. e.g. removal of hand on being touched by hot or insertion of a pin in a skin, coughing, closing of the eyelid when any object enters in the eye

But Movement of the diaphragm during respiration is due to movement of Ribs muscles and Yawning and sneezing are involuntary actions not reflex actions.
So, the correct answer is 'Coughing and removal of hand on being touched by hot object'