Tag: zoology

Questions Related to zoology

Select the incorrectly matched pair.
zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. End products of alcoholic - Ethanol + ${CO} _{2}$

  2. End products of lactic acid fermentation - Lactic acid + ${CO} _{2}$

  3. Glycolysis - Cytoplasm

  4. Key product of glycolysis - Pyruvic acid

Show answer
Correct Option: B
Explanation:
Lactic acid fermentation occurs in lactic acid bacteria (e.g., Lactobacillus), some fungi and muscles. In lactic acid fermentation, pyruvic acid produced in glycolysis is directly reduced by NADH to form lactic acid. No ${CO} _{2}$ is produced. The enzyme is lactate dehydrogenase which requires FMN and ${Zn}^{2+}$.

$Pyruvic \,\,acid+NADH\xrightarrow[FMN,{Zn}^{2+}]{Lactate \,\,denydrogenase}Lactic \,\,acid+{NAD}^{+}$

So the correct answer is 'End products of lactic acid fermentation - Lactic acid + ${CO} _{2}$'.

In which of the following situation we have to use R.I.C.E. remedy?

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Frcature

  2. Sunstroke

  3. Contusion

  4. Epilepsy

Show answer
Correct Option: A
Explanation:

RICE-Rest, Ice, Compression, Elevation. As soon after an injury like an ankle sprain, fracture pain can be relived with RICE. Rest and protect the area of injury.

Apply some ice to limit inflammation and pain.
Compression-Wrapping the injured area with bandage Elevation.
So the correct option is 'Fracture'. 

The main cause for muscle fatigue 

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Acetic acid

  2. Water

  3. Lactic acid

  4. Hydro chloric acid

Show answer
Correct Option: C
Explanation:

Intracellular acidosis due mainly to lactic acid accumulation has been regarded as the most important cause of skeletal muscle fatigue. Inorganic phosphate, which increases during fatigue due to the breakdown of creatine phosphate appears to be a major cause of muscle fatigue.

So, the correct option is 'Lactic acid'.

Which of the following is not true about rigor mortis?

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. It is irreversible.

  2. It is not a permanent contraction.

  3. ATP increases in muscles.

  4. Time of onset is not same in all muscles.

Show answer
Correct Option: C
Explanation:

Rigor mortis is the state of rigidity that develops in the muscles after death. It is used to determine or estimate the time of death. This refers to the stiffening of the body after death due to loss of Adenosine Triphosphate (ATP) from the body's muscles. ATP provides the energy to the muscles which help them to work and without this, the muscles become stiff and inflexible. 

The longest phase in a single muscle twitch in a vertebrate is about 50 millisec and is ................. phase.

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Latent

  2. Contraction

  3. Relaxation

  4. All are equal

Show answer
Correct Option: C
Explanation:

Muscle twitch is the response of a muscle to a single electrical stimulation. It is divided into three phases: latent period - time between stimulation and beginning of shortening, contraction phase - time of shortening, relaxation phase- time when muscle is returning to resting length (longest phase).

Rigor mortis is 

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Contraction of muscles after death

  2. Contraction of muscles before death

  3. Shivering of muscles

  4. None of the above

Show answer
Correct Option: A
Explanation:

Rigor mortis is stiffening of the body caused by contraction of muscles after death. In humans it occurs four hours after death. Due to absence of oxygen after death, the ATP is not formed which is required for separation of actin and myosin. When oxygen is no longer present, the body may continue to produce ATP via anaerobic glycolysis. When the body's glycogen is depleted, the ATP concentration diminishes, and the body enters rigor mortis because it is unable to break those bridges. So, the correct answer is 'Contraction of muscles after death'.

TLV' stands for

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Temperature limit value

  2. Threshold Limit Value

  3. Tropical limit value

  4. Time Limit value

Show answer
Correct Option: B

Exposure to $H _{2}S$ for a short period, causes

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Vomiting

  2. Mortality

  3. Fatigue

  4. Unconsciousness

Show answer
Correct Option: C

Contraction of shortest duration is of

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Heart

  2. Eyelids

  3. Arm

  4. Jaws

Show answer
Correct Option: B
Explanation:

The external muscles of the eye are conspicuously large and strong in relation to the small size and weight of the eyeball. It is frequently said that they are the strongest and fastest contracting muscles due to the constant blinking action they have to do. Eye movements do require high speed movements, and eye muscles are exercised continuously even during rapid eye movement of sleep. 

When supra maximal stimulus is given then

zoology skeleton and movements features of a muscle muscle features muscle contraction and its effects

  1. Muscle contraction is more than normal

  2. Muscle contraction is less than normal

  3. Muscle contraction is below average

  4. None of the above

Show answer
Correct Option: A
Explanation:

At the maximal stimulus, all motor units are recruited. All muscle cells in the whole muscle are contracting. Any stimulus above the maximal stimulus is called a supramaximal stimulus (voltage) and the tension will not increase beyond that elicited by a maximal stimulus. Thus, the correct answer is option A.