Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

The chemicals which are released at the synaptic junction are known as

  1. Cerebrospinal fluid

  2. Hormones

  3. Neurotransmitters

  4. Lymph
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Neurotransmitters are the brain chemicals that communicate information throughout our brain and body. They relay signals between nerve cells called as neurons. They are the chemicals which allow the transmission of signals from one neuron to the next across synapses. They are also found at the axon endings of motor neurons, where they stimulate the muscle fibres. So, the correct answer is option C.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Select the option responsible for restoring resting membrane potential of a neuron

  1. Voltage gated ${ Na }^{ + }$ channels
  2. Voltage gated ${ K }^{ + }$ channels
  3. Leaky channels for ${ K }^{ + }$
  4. ${ Na }^{ + }/{ K }^{ + }$ pump
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Sodium-Potassium pump is the process of moving sodium and potassium ions across the cell membrane is an active transport process involving the hydrolysis of ATP to provide the necessary energy. It involves an enzyme referred to as Na+/K+.

So, the correct option is 'Na+/K+ pump'.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Nerve impulse generation is a

  1. Physical process

  2. Chemical process

  3. Effected process

  4. Electro-chemical process
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
A nerve impulse is a way nerve cells (neurons) communicate with one another. Nerve impulses are mostly electrical signals along the dendrites to produce a nerve impulse or action potential. The action potential is the result of ions moving in and out of the cell.
Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

In thinking and response to external stimulus the brain take time about

  1. Less than 1/10th sec

  2. 1/10th sec

  3. More than 1/10th sec

  4. About 1 sec
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The human nervous system is highly developed. The external stimulus leads to generation of impulse. This impulse is conducted through sensory neurons and the response is given by the effector organ on receiving the answer given by the brain. The time taken by the brain and the nervous system to give the response is considered as in fraction of a second. So, the correct answer is option B.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

You are watching a horror movie and you notice your heart is beating fast and mouth is dry; it is because

  1. Fight and flight response

  2. Autonomic nervous system

  3. Sympathetic nervous system

  4. Both A and C

  5. Release of acetylcholine
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
You are watching a horror movie and you notice your heart is beating fast and mouth is dry; it is because of fight and flight response and sympathetic nervous system.
Fight and flight response is acute stress response.
The fight-or-flight response occurs in response to a perceived harmful event, attack, or threat to survival. The sympathetic nervous system originates in the spinal cord and its main function is to activate the physiological changes that occur during the fight-or-flight response. This component of the autonomic nervous system utilizes and activates the release of norepinephrine in the reaction.
The physiological changes that occur during the fight or flight response are activated in order to give the body increased strength and speed in anticipation of fighting or running. Some of the specific physiological changes and their functions include:
Increased blood flow to the muscles activated by diverting blood flow from other parts of the body.
Increased blood pressure, heart rate, blood sugars, and fats in order to supply the body with extra energy.
The blood clotting function of the body speeds up in order to prevent excessive blood loss in the event of an injury sustained during the response.
Increased muscle tension in order to provide the body with extra speed and strength.
Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Sight of delicious food usually makes mouth watery, it is a 

  1. Hormonal response

  2. Neural response

  3. Optic response

  4. Olfactory response
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The response to food begins even before food enters the mouth. The first phase of ingestion, called as the cephalic phase, is controlled by the neural response to the stimulus provided by food. All aspects, such as sight, sense, and smell, trigger the neural responses resulting in salivation and secretion of gastric juices. The gastric and salivary secretion in the cephalic phase can also take place at the thought of food. The central nervous system prepares the stomach to receive food. 

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Who discovered synapse?

  1. R. Y. Cahal

  2. Sherrington

  3. Otto Loewi

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The term synapse was first discovered in 1897 by neurophysiologist Charles Sherrington. The gap between two neurons across which impulses are conducted is known as a synapse. Synapse is a structure that permits a neuron to pass an electrical or chemical signal to another cell. It is important for neuronal function. 
Thus, the correct answer is option B.

Multiple choice biology life processes: control and coordination nervous system in animals structure of neuron structure and function of neuron

Destruction of the anterior horn cells of the spinal cord would result in loss of

  1. Sensory impulses

  2. Voluntary motor impulses

  3. Commissural impulses

  4. Integrating impulses.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Anterior horn cells are the ventral (front) grey matter section of the spinal cord which contains motor neurons that affect the skeletal muscles. It is also known as anterior grey column, ventral horn. The anterior grey column is the column where the cell bodies of alpha motor neurons are located. The destruction of the anterior horn cells of the spinal cord would result in loss of voluntary motor impulses because it is mainly related to motor impulses.

So, the correct answer is option B. 

Multiple choice biology water and air and their importance the lithosphere and the hydrosphere first aid safety and first aid

Which of the following explains drought?

  1. Low rainfall than requirement

  2. High rainfall than requirement

  3. Low pressure in atmosphere

  4. High pressure in atmosphere
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A drought is a period of drier-than-normal conditions that results in water-related problems, primarily caused by a significant deficit in expected rainfall.

Multiple choice biology reproduction growth and development in plants sexual reproduction in plants post fertilization - plants

After fertilization, ............ develops into seed and ............ into fruit.

  1. Ovary, Ovule

  2. Ovule, Ovary

  3. Embryo sac

  4. Egg cell
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fertilization occurs when one of the sperm cells fuses with the egg inside of an ovule. After fertilization occurs, each ovule develops into a seed. Each seed contains a tiny, undeveloped plant called an embryo. The ovary surrounding the ovules develops into a fruit that contains one or more seeds.

So, the correct answer is 'Ovule, Ovary'.