Answer: The cell wall surrounds the plasma membrane of plant cells and provides tensile strength and protection against mechanical and osmotic stress.
Variation means difference in genetic makeup between individuals within a specie.
In human blood, there is a compound inside the RBCs called haemoglobin which ensures that the muscle will receive enough oxygen during exercise.
<h3><u>Explanation:</u></h3>
In human blood, the red blood corpuscles contain the haemoglobin. Haemoglobin is a iron chelated compound containing porphyrin ring and a globin tail which can establish co-ordinate covalent bond with both oxygen and carbon dioxide. The bonding element depends on the concentration of these two gases. In lungs, where the oxygen concentration is more than carbon dioxide, the haemoglobin bonds with oxygen and brings it to the tissues where carbon dioxide concentration is more. This makes the haemoglobin to release oxygen and bond with carbon dioxide which is brought back to lungs. This is the process by which each and every tissue including the muscles recieve oxygen.
In muscles there is Myoglobin which is another iron-porphyrin compound which has several times more affinity for oxygen than haemoglobin. This helps to extract more oxygen from haemoglobin in muscles.
Answer:
1. myosin ATPase
2. Ca2+-ATPase
Explanation:
ATPase activity of myosin head hydrolysis ATP and energize the myosin head. The energized myosin head forms cross bridges to facilitate the power stroke of muscle contraction. The fast-twitch oxidative-glycolytic fibers have the ability to produce ATP by aerobic respiration.
These fibers have the ATPase in their myosin heads that hydrolyze ATP three to five times faster than the myosin ATPase in slow fibers. This ensures the faster speed of contraction of these fast-twitch muscle fibers.
During their relaxation, Ca2+ ATPase pumps the calcium ions back to the sarcoplasmic reticulum. As the level of Ca2+ ions in the sarcoplasm decreases, calcium ions are released from troponin. Tropomyosin is allowed to cover the myosin-binding sites on actin and the muscle fiber relaxes faster.
You didn't attached the choice but then I have two answer either of the two is correct. The first one is Putamen , is located on the base of the telencephalon (forebrain). Second answer is Angular gyrus is a region part of the brain and it is involved in number of processing related to number processing and spatial cognition, language, attention and memory retrieval.