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Explain how cystic fibrosis affects digestion, gas exchange and reproduction.

Background information I would give to the student: This question is a perfect example which shows that if you really understand the topic, it becomes easier to remember the facts for the questions relating ...
SG
Answered by Shaswath G. • Biology tutor
10028 Views

What is the difference between the Parasympathetic Nervous System and the Sympathetic Nervous System?

The Nervous System can be split into three central pathways.The SNS and PNS are part of the Autonomic Nervous System, the autonomic nervous system is responsible for the involuntary actions of the human body...
VR
10593 Views

Describe how phagocytosis of a virus leads to presentation of its antigens (3 marks)

Virus engulfed by phagocyte (broad immune response), destroyed using lysosomes (hydrolysis) and viral antigens presented on cell membrane (trigger specific immune response e.g. anti-bodies). Steps of phagocy...
BJ
Answered by Ben J. • Biology tutor
27970 Views

Describe the function of enzymes DNA helicase and DNA polymerase during DNA replication (2 marks)

DNA replication occurs in two phases: DNA separation (DNA helicase) and DNA transcription (DNA polymerase) Enzyme Function: 1. DNA helicase – (unwinding DNA and) breaking hydrogen bonds between DNA strands (...
BJ
Answered by Ben J. • Biology tutor
10722 Views

What is the sequence of events for muscle contraction?

· The myosin head attaches to the myosin binding site on the actin filament forming an actinomyosin bridge · ATP is hydrolysed to ADP and inorganic phosphate as the cross-bridge forms (ATP hydrolase is activ...
LB
Answered by Letisha B. • Biology tutor
36945 Views