Ammonoids are good as index fossils because of the following characteristics;
<span>1.
</span>Their abundance and vast distribution across most shallow
marine waters during the periods
<span>2.
</span>They have easily recognizable
features, such as shells and the highly crenulated and complex suture, that are well preserved in rocks
<span>3.
</span>Their rapid
evolution that can assist determine changes and variations in the then environment
Answer:
B: <em>mitochondria produce the water from oxygen and the chloroplast produces oxygen from water.</em>
Explanation:
Answer: I believe the answer would be 2
Explanation:
The cramps can be caused due to anaerobic respiration in the muscles and lactic acid formation.
During intense physical activity the muscles become deprived of oxygen, in this condition, anaerobic respiration takes place in the muscle cells causes the formation of the lactic acid.
The physical training increases the strength of the muscles, which can help the muscles not to get tired easily. that is why, physical training is required before any marathon.
