Tag: locomotion and reproduction

In the axoneme of cilia and flagella, the peripheral microtubule doublets are typically tilted at an angle of approximately 10 degrees.

Flagella are found in both eukaryotic cells (like sperm cells or Chlamydomonas) and prokaryotic cells (like E. coli), although their structures are fundamentally different.

• Axoneme with 9+2 microtubular arrangement occurs in both cilia and flagella.
  
• Cilia and flagella are cellular projections which are covered by an extension of the plasma membrane. 
  
• They both have similar internal structures and are made up of microtubules.
• The microtubule arrangement within cilia and flagella is 9 + 2 arrangement of microtubules.
• It contains nine fused pairs of microtubules on the outer side of a cylinder and the two unfused microtubules at the centre.
• So, the correct answer is 'Both A and B'.

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.

Calcium-dependent kinases (such as CDKs or CaMKs) play crucial roles in regulating various cellular processes, including the progression of the cell cycle.

Cilia are short, hair-like appendages found on the surface of many cells. They are typically numerous and move in a coordinated, sweeping, or pendular fashion to move fluid or particles across the cell surface.

Flagella are typically longer than cilia and move in a wave-like (undulatory) motion. This motion is generally independent of other flagella and symmetric in its wave propagation.

• 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'.

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.