Tag: biology

Questions Related to biology

How many chromosomes will the cell have at GI, after S and after M-phase respectively if it has 14 chromosomes at interphase

biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. 7, 14, 14

  2. 14, 14, 14

  3. 14, 14, 7

  4. 7, 7, 7

Show answer
Correct Option: B
Explanation:

At G1 phase, there will be 14 chromosomes as no DNA replication has taken place. After S Phase, the DNA content doubles but chromosome number still remains same here 14. After completion of M phase, the number of chromosomes will be 28 with each daughter cell having same number of chromosomes as that of parent i.e 14

Therefore B is the correct option. 

Match the lists and choose the correct option:

a. $G _1$ phase i. Replication of DNA
b. S-phase ii. Quiescent stage
c. $G _2$-phase iii. Condensation chromatin
d. $G _0$-phase iv. Protein synthesis
v. Interval between mitosis and initiate of DNA replication
biology division for growth and reproduction cell division in embryo development structure of chromosome, cell cycle and cell division component of the cell different types of reproduction reproductive health of humans need of family planning tissues of animals mitosis reproductive health

  1. a-iii, b-ii, c-i, d-ii

  2. a-v, b-iv, c-i, d-iii

  3. a - v, b -i, c - iv, d-ii

  4. a v, b -ii, c-iii, d - iv

Show answer
Correct Option: C
Explanation:
Interphase generally lasts at least 12 to 24 hours in mammalian tissue. During this period, the cell is constantly synthesizing RNA, producing protein and growing in size. Interphase can be divided into 4 steps: Gap 0 (G0), Gap 1 (G1), S (synthesis) phase, Gap 2 (G2).
Gap 0 (G0): There are times when a cell will leave the cycle and quit dividing
Gap 1 (G1): Cells increase in size in Gap 1, produce RNA and synthesize protein.
S Phase: To produce two similar daughter cells, DNA replication occurs during this S (synthesis) phase.
Gap 2 (G2): During the gap between DNA synthesis and mitosis, the cell will continue to grow and produce new proteins.
Hence answer is 'a - v, b -i, c - iv, d-ii'

In man the axial skeleton is made up of

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. 80 bones

  2. 100 bones

  3. 103 bones

  4. 106 bones

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Correct Option: A
Explanation:

It forms the main axis. It consists of skull - 22 bones vertebral column - 33 vertebrae, sternum - 1 and ribs - 24.

Read the following matches 
(i)   Glenoid cavity            - Scapula
(ii)  Bicipital tuberosity     - Humerus
(iii) Styloid process           - Ulna
Which of these is correct?

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. (i) and (ii)

  2. (i) & (iii)

  3. (i) and (iii)

  4. All are correct

Show answer
Correct Option: B
Explanation:

A- The glenoid cavity or glenoid fossa of scapula is a part of the shoulder. It is a shallow, pyriform articular surface, which is located on the lateral angle of the scapula.

B- The rough eminence which is on the anterior inner aspect of the neck of the radius and into which the tendon of the biceps is inserted.
C- The styloid process of the ulna is found at distal end of the forearm, and projects from the medial and back part of the bone.

So, the correct option is 'Option B'. 

Which bones are present in both hands and foot? Name the only movable bone in the skull of man.

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. Tibia - Maxilla

  2. Radius - Lacrimal

  3. Phalanges - Mandible

  4. Phalanges - Maxilla

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Correct Option: C
Explanation:
  • The phalanges are digital bones in the hands and feet of most vertebrates. In primates, the thumbs and big toes have two phalanges while the other digits have three phalanges.
  •  Hence, Phalanges are present in both hands and foot.
  • The mandible is the largest, strongest and lowest bone in the human face. It forms the lower jaw and holds the lower teeth in place. The mandible is the only movable bone of the skull, not counting the ossicles of the middle ear.
  • Hence, Mandible is the only movable bone in the skull of the man.
  • So, the correct answer is 'Phalanges - Mandible'.

Which of the following is not fully formed in birds?

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. Pectoral girdle

  2. Pelvic girdle

  3. Hind limb

  4. Fore limb

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Correct Option: D
Explanation:

The main characteristic that is associated with birds is their ability to fly. The entire forelimb has been modified to become a wing. The forelimb is not required to support weight but to restrain prey or for locomotion. 

Number of bone is each upper limb is?

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. $1, 1, 1$

  2. $8, 5, 14$

  3. $2, 2, 2, 16, 10, 28$

  4. $1, 1, 1, 8, 5, 14$

Show answer
Correct Option: A

In the middle lateral side a cup shaped cavity or acetabulum (for head of femur) is present in the region of union of

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. Ilium and ischium

  2. Ilium and pubis

  3. Ilium, ischium and pubis

  4. Ischium and pubis

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Correct Option: C
Explanation:

The hip joint is a synovial joint formed by the articulation of the rounded head of the femur and the cup-like acetabulum of the pelvis. The cup-like acetabulum forms at the union of three pelvic bones - the ilium, pubis, and ischium. 

So, the correct option is C. (ilium, ischium and pubis)

Bones act as ________ during locomotion.

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. Levers

  2. Fulcrum

  3. Pulleys

  4. Points

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Correct Option: A
Explanation:

Bones provide a supporting structure for the body. It gives a framework to the body that helps in maintaining the shape to the body and they also provide surface so that muscles can be attached. Further. bones act as a lever during locomotion so it is able to turn one axis.
Hence , option  A ( Levers ) is correct.

A cup shaped cavity for articulation of femur head is

biology skeleton, joints and muscles skeleton our skeletal system and the skin skeleton - movement and locomotion

  1. Acetabulum

  2. Glenoid cavity

  3. Sigmoid notch

  4. Obturator foramen

Show answer
Correct Option: A
Explanation:

Pelvic girdle consists of two coxal bones. Each coxal bone is formed by the fusion of three bones ilium, ischium and pubis. At the point of fusion of the above bones is a cup shaped cavity called as acetabulum to which the thigh bone articulates. The two halves of the pelvic girdle meet ventrally to form the pubic symphysis containing fibrous cartilage.