The early shape of the fetal brain most resemble a tube. The fetal development starts after conception. After about four weeks the neural tube together with the back is closing. The fetal brain and the spinal cord will develop from the neural tube. Then the other organs and the heart are also starting to form.
B: Neurons have dendrites, axons, and a cell body
Answer: It provides protection of the body by white blood cells, antibodies, and complement proteins that circulate in the blood and defend the body against foreign microbes and toxins. Clotting mechanisms are also present that protect the body from blood loss after injuries.
Answer:
At the beginning, aerobic respiration is used by his legs to generate energy when there was still sufficient oxygen intake for energy to be generated via oxidative phosphorylation.
Towards the end of the ride, his legs are generating energy through anaerobic respiration due to insufficient oxygen intake to keep up with the energy requirement of his muscles as he cycles continuously. Through anaerobic respiration, pyruvate from glycolysis is converted to lactate by lactate dehydrogenase instead of being channelled to the mitochondria for oxidative phosphorylation. The accumulation of lactate in his muscles is what causes the pain in his leg. After he stops the activity, the pain would reduce as lactate is transported to the liver to be reconverted back into pyruvate.
The heat from hot liquid can make the cup it’s in hot. When you make some food in a pot with boiling water and stick a metal spoon/fork into the pot to move the food around the boiling water then makes the spoon/fork hot.