Top answers


Describe the five stages of phagocytosis of a bacterium by a neutrophil

Attraction of phagocyte (neutrophil), towards the bacterium 2) Neutrophil engulfs the pathogen, forming a phagosome3) Formation of lysosomes which are attracted to the phagosome4) Binding of lysosomes to the...
MB
Answered by Mahesh B. • Biology tutor
4180 Views

Describe how HIV replicates in the human body

The HIV life style has 7 stages. The first is binding: HIV has glycoproteins embedded in the membrane that help it to bind to CD4 receptors on the surface of a human cell. Next, the HIV envelope and human ce...
MM
Answered by Maree M. • Biology tutor
9337 Views

Describe how muscle cells contract

An action potential depolarises the sarcoma and depolarisation travels down the T-tubules to the sarcoplasmic reticulum, which releases Ca 2+ (calcium ions) to the sarcoplasm. Ca 2+ cause tropomyosin to chan...
MS
Answered by Maria S. • Biology tutor
3290 Views

Describe the process of ultrafiltration in the Kidneys.

Ultrafiltration occurs in the nephron, the functional unit of the kidney. Blood enters a coiled network of vessels called the glomerulus from the afferent arteriole at a high hydrostatic pressure. The glomer...
MM
Answered by Matthew M. • Biology tutor
23504 Views

Describe the structure of globular proteins.

There are 4 levels of structure associated with a globular protein; primary, secondary, tertiary and quarternary. The primary structure is the organisation of amino acids, bonded by peptide bonds. The second...
CK
Answered by Charlie K. • Biology tutor
11926 Views