False
their legs were made form the spine of stingrays and they were used to ward of bad storms.
Biology is the study of life, and uses the scientific method, the basis of science, to do so. Hypotheses are made, tested, and remade, until a theory is made, which then becomes Scientific law.
The main reason why carbon atoms are so common in living things is because carbon is a very adaptable element in the sense that its electron configuration allows it to bond with many other atoms.
Answer:
<em>Kreb cycle occurs in mitochondrial matrix and electron transport system occurs in the inner membrane of mitochondria.</em>
The normal membrane potential inside the axon of nerve cells is –70mV, and since this potential can change in nerve cells it is called the resting potential. When a stimulus is applied a brief reversal of the membrane potential, lasting about a millisecond, occurs. This brief reversal is called the action potential
<span>A stimulus can cause the membrane potential to change a little. The voltage-gated ion channels can detect this change, and when the potential reaches –30mV the sodium channels open for 0.5ms. The causes sodium ions to rush in, making the inside of the cell more positive. This phase is referred to as a depolarisation since the normal voltage polarity (negative inside) is reversed (becomes positive inside). </span>
<span>Repolarisation. At a certain point, the depolarisation of the membrane causes the sodium channels to close. As a result the potassium channels open for 0.5ms, causing potassium ions to rush out, making the inside more negative again. Since this restores the original polarity, it is called repolarisation. As the polarity becomes restored, there is a slight ‘overshoot’ in the movement of potassium ions (called hyperpolarisation). The resting membrane potential is restored by the Na+K+ATPase pump.</span>
