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Explain how a rise in blood pressure results in a decrease in the rate of heartbeat.

Baroreceptors detect the rise in blood pressure in the aorta, they send impulses to the cardiovascular centre. Then, impulses are sent via parasympathetic nerves to the SAN. This triggers the release of ACh,...
KS
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Explain the role of anti-diuretic hormone in osmotic homeostasis.

Anti-diuretic hormone (ADH) is produced by the hypothalamus and stored in the posterior pituitary gland. When the hypothalamus identifies the bloods osmotic pressure as being outside the homeostatic range, t...
JB
Answered by Jonathan B. • Biology tutor
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How are polynucleotide DNA strands held together? (3 marks)

The two antiparallel strands of DNA are held together by hydrogen bonds joining the bases of each complementary nucleotide; Adenine is held to Thymine by 2 hydrogen bonds, and Guanine to Cytosine by 3 hydrog...
SA
Answered by Srishti A. • Biology tutor
10737 Views

Why does an action potential travel faster in a myelinated neurone compared to a non-myelinated neurone?

Myelinated and non-myelinated neurones have different structures which is why the speed of action potentials differ. In a Myelinated neurone, a myelin sheath is wrapped around the axon. This myelin sheath is...
SF
Answered by Saima F. • Biology tutor
17424 Views

Based on structure, how is an enzyme's function affected by amino acids?

An enzyme is a type of protein, and proteins are made up of amino acids. The sequence of amino acids determines the shape of the enzyme, which in turns controls which substrates will or won't fit into the ac...
CC
Answered by Chester C. • Biology tutor
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