Tag: zoology

Questions Related to zoology

Identify the wrong statement regarding white muscles

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. Have more blood capillaries than red muscle fibres

  2. Have less blood capillaries than red muscle fibres

  3. Have less number of mitochondria than red muscle fibres

  4. Have more sarcoplasmic reticulum than red muscle fibres

Show answer
Correct Option: A
Explanation:
  • Red Muscle Fibre: These muscle fibres are dark red which is due to the presence of red haemoprotein called myoglobin.
  •  Myoglobin binds and stores oxygen as ooxymyoglobinin the red fibres.
  • Oxymyogiobin releases oxygen for utilization during muscle contraction. Hence, white muscles have more blood capillaries than red muscle fibre is  the wrong statement regarding white muscles.
  So, the correct answer is 'Have more blood capillaries than red muscle fibres'/

Which of the following is correct statement for white muscle fibre?

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. It contains low amount of haemoglobin and mitochondria.

  2. It contains higher amount of myoglobin.

  3. It contains low amount of myoglobin and mitochondria.

  4. It possesses only actin type of protein.

Show answer
Correct Option: C
Explanation:
  • Muscle is a  bundle of fibrous tissue in a body that has the ability to contract, producing movement in or maintaining the position of parts of the body.
  • The total number of muscles in the human body comes in the range of 640-850.
  • Muscles appear in red colour due to a pigment called myoglobin. It receives oxygen from the red blood cells and transports it to the mitochondria of muscle cells, where the oxygen is used in cellular respiration to produce energy. 
  • Muscle fibres are named as white muscle fibres because It contains a low amount of myoglobin and mitochondria.compared to red muscle fibres.
  • So, the correct answer is 'It contains a low amount of myoglobin and mitochondria'.

The slow twitch muscle fibres which are rich in myoglobins and have abundant mitochondria are:

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. white skeletal muscles

  2. cardiac muscles

  3. red skeletal muscles

  4. involuntary muscles

Show answer
Correct Option: A
Explanation:

The slow twitch muscle fibres which are rich in myoglobins and have abundant mitochondria are 'white skeletal muscles'.

Identify from the following list, the characteristics of red muscles (A) and white muscles (B) and select the option that correctly segregates the characters.
(i) Less number of mitochondria
(ii) More number of mitochondria
(iii) Sarcoplasmic reticulum is abundant
(iv) Myoglobin content high
(v) Sarcoplamic reticulum moderate
(vi) Aerobic muscles
(vii) Depend on anaerobic respiration. for energy
(viii) Less myoglobin content 

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. (i), (iii), (vii), (viii) (ii), (iv), (v), (vi)

  2. (ii), (iv),(vi), (v),(i), (vii), (viii),(iii)

  3. (i), (iii), (iv), (vii) (ii), (v), (vi), (viii)

  4. (ii), (v), (vi), (viii) (i), (iii), (iv), (vii)

Show answer
Correct Option: B

Match the following and mark correct option:

Column I Column II
A. Fast muscle fibres (i) Myoglobin
B. Slow muscle fibres (ii) Lactic acid
C. Actin filament (iii) Contractile unit
D. Sarcomere (iv) I-band 
zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. A-(i), B-(ii), C- (iv), D- (iii)

  2. A-(ii), B-(i), C - (iii), D- (iv)

  3. A-(ii), B-(i), C - (iv), D- (iii)

  4. A-(iii), B-(ii), C - (iv), D- (i)

Show answer
Correct Option: C
Explanation:
The sarcomere is known as the ultimate unit of contraction. It is made up of actin and myosin filament.
Actin filaments are the ones that are also known as the thin filament and forms the isotropic part in the sarcomere.
Few fast muscle fibres are the ones that are present in the type of runners that runs for a short amount of time. They have high glycogen content and lactic acid contained in them because of anaerobic respiration and muscle fatigue.
Slow muscle fibre is found in those runners that need to have long and sturdy run. They have a high number of mitochondria and myoglobin because they need continuous ATP production or a large amount of time.
So, the correct option is 'A-(ii), B-(i), C - (iv), D- (iii)'



Which of the following correctly characterises a "fast-oxidative" type of skeletal muscle fibre?

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. Few mitochondria and high glycogen content

  2. Low myosin ATPase rate and few surrounding capillaries

  3. Low glycolytic enzyme activity and intermediate contraction velocity

  4. High myoglobin content and intermediate glycolytic enzyme activity

Show answer
Correct Option: A
Explanation:

Fast oxidative type of muscle fibres is generally found in the sprinters that need to run for a short amount of time. They do not need to have a very large number of mitochondria for continuous ATP production but they do need to have speed. So in such muscle fibres, there is a high glycogen content which is converting into lactic acid rapidly and fatigue is caused more early.

So, the correct option is 'Few mitochondria and high glycogen content'

Which of the following match is incorrect?

zoology musculo-skeletal system red and white muscle types of muscle fibres locomotion and movements

  1. Red muscle - Large amount of mitochondria

  2. White muscle - Fight muscles of the birds

  3. Smooth muscle - Innervated by autonomous nervous system

  4. Cardiac muscle - Abundant blood supply

Show answer
Correct Option: B
Explanation:

Red muscles contain a large amount of mitochondria as it requires large amount of energy. White muscles contain fewer mitochondria. Pectoralis major is the flight muscles of the birds. It helps birds to flight. It is a red muscle. The autonomic nervous system is involuntary. It controls cardiac and smooth muscles, glands and blood vessels. Cardiac muscle has abundant blood supply. It extracts approximately 75% of the oxygen from blood in the left ventricle. 

Thus, the correct answer is 'White muscle - Fight muscles of the birds.'

A sequential expression of a set of human genes occurs when a steroid molecule binds to the

zoology molecular genetics one gene - one enzyme hypothesis component of the cell cell and cell organelles

  1. Transfer RNA

  2. Messenger RNA

  3. DNA sequence

  4. Ribosome

Show answer
Correct Option: C
Explanation:

Steroid hormone are chemical messengers that interact or bind with the DNA inside the nucleus

For example, Oval albumin synthesis in oviduct of chick is influenced by estrogen (steroid) (Transcriptional control) 

On which organism Beadle and Tatum worked to propose one gene-one enzyme hypothesis?

zoology molecular genetics one gene - one enzyme hypothesis component of the cell cell and cell organelles

  1. Drosophila

  2. Escherichia coli

  3. Neurospora crassa

  4. Nostoc

Show answer
Correct Option: C
Explanation:

George Beadle and Edward Tatum gave molecular definition of a gene while working on nutritional mutants in Neurospora. They exposed spores of the fungus Neurospora crassa to X-rays and other agents which damage DNA and cause alterations in DNA sequence (mutations). They observed that mutant fungal strains which lacked one or another specific enzyme, sometimes results in the failure of an entire metabolic pathway. It was concluded that a gene is a segment of genetic material that codes for one enzyme; the one gene–one enzyme hypothesis which was modified to one gene–one polypeptide, because many genes products are not enzymes and many gene code for one polypeptide of a multi-subunit protein. Correct option is C.

One gene-one enzyme hypothesis was postulated by

zoology molecular genetics one gene - one enzyme hypothesis component of the cell cell and cell organelles

  1. R. Franklin

  2. Hershey and Chase

  3. A. Garrod

  4. Beadle and Tatum

Show answer
Correct Option: D
Explanation:
Beadle and Tatum did classical experiments on Neurospora crassa to prove that in a multistep biochemical pathway, each step is controlled by different enzymes and each of these enzymes are encoded by specific gene. This is called as one gene one enzyme hypothesis
So, the correct answer is 'Beadle and Tatum'