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Describe the role of calcium ions and ATP during muscle contraction

Calcium ions diffuse from the sarcoplasmic reticulum and bind to troponin. This binding to troponin causes tropomyosin- which at rest blocks the actin-myosin binding sites- moves to expose these binding s...

Answered by Johanna H. • Biology tutor

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Respiration transfers energy from glucose for muscle contraction. Describe how glucose from the small intestine is moved to a muscle cell.

Glucose is absorbed by diffusion into the bloodstream./ Then blood delivers glucose to muscles in capilleries.

Answered by LUKE S. • Biology tutor

17146 Views

Microorganisms cause diseases. The human body has many ways of defending itself against microorganisms. Describe two ways the body prevents the entry of microorganisms.

Any two from:acid in the stomach kills pathogens in food/ skin forms a barrier or produces antimicrobial secretions/ hairs in the nose trap pathogens/ trachea or bronchi has mucus which traps pathogens

Answered by LUKE S. • Biology tutor

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Steve, a novice gardener, plants sunflower seeds into small pots. He does not water them and is upset that they have not grown a week later. Explain why water is needed for the germination of a seed and what other conditions are required also and why

Preparation: This is a complex question requiring several strands of knowledge. It is best to break down the question into smaller chunks and answer each of those, to gain maximum marks. ...

Answered by Simran D. • Biology tutor

1790 Views

What are the key features of eukaryote DNA?

DNA, or deoxyribonucleic acid, is a doubled-stranded helix made up of nucleotides. Each nucleotide has one of four bases attached to it. The bases of the nucleotides of one strand base pair to the complim...

Answered by Jess T. • Biology tutor

2473 Views