Answer:phospholipids is not a part
Explanation:
D. Myosin and actin do not fully detach, so the muscle cannot relax.
The question is incomplete. The complete question is:
Question: Why do organisms without oxygen need to convert pyruvate to lactate?
A) because pyruvate is toxic to the cells
B) in order to regenerate NAD+
C) in order to use lactate in the citric acid cycle
D) because lactate is needed to produce ATP
Answer:
B) in order to regenerate NAD+
Explanation:
Kreb's cycle and electron transport chain (ETC) are the aerobic stages of cellular respiration. ETC regenerates NAD+ and FAD+ by oxidation of NADH and FADH2 produced during glycolysis and Kreb's cycle. Here, oxygen serves as the terminal electron acceptor.
Glycolytic reactions use NAD+ as an electron acceptor and produce NADH. Therefore, a constant supply of NAD+ is required to sustain glycolysis. In absence of oxygen, ETC cannot occur and organisms convert pyruvate into lactate. Pyruvate is reduced in lactate and NADH serves as the electron donor. Thereby, lactate fermentation regenerates NAD+ to continue the process of glycolysis.
The following given statements are true of trans-fatty acids:
A. Often created by treating plant oils with hydrogen
D. Occur naturally in in food
<u>Explanation:</u>
The unsaturated fatty acids that are produced by a method called hydrogenation through the addition of a hydrogen molecule to vegetable oils is understood as "Trans-fatty acids". According to the hydrogenation process the composition of the fatty acids varies. The unsaturated fatty acids trans structure receives one double conjugated bond and obtains a straight shape and rectifies the twisted shape created by cis bonds.
Increasing the concentrations of trans-fatty acids particularly in the red blood cell membranes can lead to blockage of the blood vessel as a whole and enhance the risk of heart disease. Meat and dairy products kind natural food materials include trans fatty acids.
