Describe the structure and function of a sperm cell, and the role of blood plasma in the body.

1.a) The part labelled B is the mid-piece.

1.b) The function of part C (the tail/flagellum) is to provide propulsion or movement for the sperm.

1.c) During fertilisation, part A (the acrosome) releases hydrolytic enzymes. These enzymes digest the outer layers of the egg, specifically the corona radiata and zona pellucida, allowing the sperm to penetrate and fuse with the egg cell membrane.

1.d) Two adaptations of the sperm for movement are:

• It possesses a long tail (flagellum) which whips back and forth, propelling the sperm forward.
• The mid-piece (B) contains numerous mitochondria that generate large amounts of ATP, providing the energy required for the tail's vigorous movement.

2.a) Two functions of blood plasma are:

• It transports nutrients such as glucose, amino acids, and vitamins to body cells.
• It transports waste products like urea and carbon dioxide from cells to excretory organs.
• It transports hormones and antibodies throughout the body.