It would be the first one. Hope this helps :)
<span>Because there is a lack of sufficient oxygen in muscle cells. For muscle cells to convert pyruvate into usable energy (ATP), there must be a sufficient amount of oxygen available to the cells. When there is not, the body has the ability to convert it to lactate which can provide energy when little oxygen is available.</span>
I only know the answer for No 2)
It is Microfilaments which are the part of cells skeleton.
B an allele for smith hair from each parent. They’d have to have two recessive alleles to show the trait
Blood flows to the brain through the internal carotid and vertebral arteries and away from the brain through the internal jugular vein. The internal carotid artery supplies the brain, while the external carotid nourishes other portions of the head, such as the face, skull, scalp and the meninges. The vertebral arteries provide supply to the upper spinal cord, brainstem, cerebellum, and the posterior part of the brain.
