Calcium Ions

Question 1

Ca2+ is essential in the movement of organisms:
In synapses, calcium ions …

Answer 1

regulate the transmission of impulses from neurone to neurone

Question 2

Ca2+ also stimulates muscle contraction

When an impulse reaches a muscle fibre, Ca2+ is released from the …………….

This Ca2+ binds to troponin C, removing the………………… from myosin-binding sites on actin

This allows ………………….to form when the…………………………

Answer 2

sarcoplasmic reticulum

tropomyosin

actin-myosin cross-bridges

muscle fibre contracts

Question 3

Ca2+ can also help to regulate protein channels, which affects the

Answer 3

permeability of cell membranes

Question 4

Many enzymes are activated by Ca2+, making these ions key………………… in many biological reactions

Answer 4

Regulators

Question 5

The presence of Ca2+ is also necessary for the formation of blood ………………………….

Answer 5

clots (it is known as a clotting factor)

Question 6

what is calcium ions used in

Answer 6

formation of blood clots

regulators in many biological reactions

regulate protein channels

stimulates muscle contraction

the movement of organisms: