Tag: zoology

Questions Related to zoology

Tubulin occurs in

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Microtubules

  2. Cilia and flagella

  3. Microvilli

  4. Both (A) and (B)

Show answer
Correct Option: D
Explanation:

Tubulin belongs to the protein superfamily of globular proteins.Alpha and beta tubulins polymerize into microtubules. Microtubules function in many processes like structural support, intracellular transport, and DNA segregation. Microtubules emerge from microtubule organizing center in eukaryotic cells.

Cilia and flagella contain the motor protein dynein and microtubules, in the form of two central and nine doublets surrounding it.Cilia and flagella help in locomotion in unicellular eukaryotes.
Microvilli are cellular membrane protrusions that increase the surface area for diffusion.
Therefore option D is correct.

Calcium dependent kinases can control _______________.

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Cell cycle activities

  2. DNA replication

  3. Cell surface receptors

  4. Mambrane structure

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Correct Option: A

Cilia are

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Short, 5-10 $\mu m$

  2. Numerous

  3. With sweeping or pendular movement

  4. All the above.

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Correct Option: D

A flagellum beats

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Independently, undulatory and asymmetrically

  2. Independently, undulatory and symmetrically

  3. Coordinated, pendular and symmetric

  4. Coordinated, pendular and asymmetric.

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Correct Option: B

A cilium beats

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Asymmetrically by sweeping action

  2. Symmetrically by sweeping action

  3. Symmetrically by undulatory action

  4. Asymmetrically by undulatory action

Show answer
Correct Option: A
Explanation:
  • Cilia can be defined as the tiny hair-like projections on the surface of the cell.
  • These hair-like projections help in sweeping mucus, trapped dust and bacteria in the respiratory tracts.
  • It beats asymmetrically by the sweeping action
  • The asymmetrical beating pattern consists of two strokes- effective stroke and recovery stroke.
  • In an effective stroke, the cilia are straight and generate flow in the same direction as its motion.
  • Whereas, in recovery stroke, the cilia bend parallel to the surface and creates relatively weaker backward flow.
  • So, the correct answer is 'Asymmetrically by sweeping action'.

Axoneme is a structure associated with

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Golgi bodies

  2. Only cilia

  3. Only flagella

  4. Both cilia and flagella

Show answer
Correct Option: D
Explanation:
Axoneme is the central strand of a cilium or flagellum. It is composed of an array of microtubules, typically in nine pairs around two single central ones.Cilia and flagella is made of the axoneme which is composed of microtubules and their associated proteins.

So, the correct answer is 'D'.

Movement of cilia and flagella is due to presence of

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Central sheath

  2. Dynein

  3. Radial spokes

  4. Singlet tubules.

Show answer
Correct Option: B
Explanation:

Dynein is a family of cytoskeletal motor proteins that move along microtubules in cells. They convert the chemical energy stored in ATP to mechnical work, and hence are involved in movement of cilia and flagella.

So, the correct option is 'Dyenin'.

The movement of the flagellum is regulated by 

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Plasma membrane

  2. Nucleus

  3. Basal body

  4. Ribosomes

Show answer
Correct Option: A
Explanation:

Bacterial flagella are helically shaped structures containing the protein flagellin. The base of the flagellum (the hook) near the cell surface is attached to the basal body enclosed in the cell envelope. The flagellum rotates in a clockwise or counterclockwise direction, in a motion similar to that of a propeller. This movement is regultaed by plasma membrane.

Thus, the correct answer is 'Plasma membrane.'

Find the correct statement in relation to flagella: 

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. Flagella are longer and less in number than cilia.

  2. Flagella usually beat independently.

  3. Arms of subfibril A are made of Nexin protein.

  4. A-B linker is made of dyenin protein.

Show answer
Correct Option: A
Explanation:

Flagella are long, numerous hairlike projections from the plasma membrane. Flagella are longer and less in number than cilia. In multicellular organisms, cilia and flagella are the major means of locomotion in prokaryotic cells, both cilia and flagella are composed of microtubles.

So, the correct option is 'Flagella are longer and more in number than cilia'.

The movement of cilia and flagella is due to the presence of _________.

zoology locomotion and reproduction flagella other cell components single membrane bound organelles

  1. radial spokes

  2. central sheath

  3. singlet micritubules

  4. dyneins

Show answer
Correct Option: D
Explanation:

Groups of dynein molecules responsible for movement in opposite directions are probably activated and inactivated in a coordinated fashion so that the cilia or flagella can move back and forth.