Phytoplankton <span>are the smallest organisms in the ocean, and largely responsible for the generation of our oxygen.</span>
Answer:
Hemoglobin is responsible for binding and transporting oxygen in the body. It is a tetrameric protein that is found in high concentration in red blood cells (erythrocytes, red blood cells). Each hemoglobin molecule is made up of four subunits: two of the alpha type and two of the beta type, and each subunit can bind an oxygen molecule through its heme group.
Structure studies have shown that hemoglobin can adopt two conformations, called T (tense) and R (relaxed). Deoxyhemoglobin (in blue) is in state T, and the union of oxygen (in red) causes the transition to state R. The animation shows a close view of the heme group (in white, balls and rods) of one of the subunits of hemoglobin. In the deoxygenated state (T), the iron atom is not coplanar with the rest of the heme group due to its association with the histidine side chain. The union of oxygen displaces the iron atom so that it remains coplanar with the rest of the heme group, which in turn drags histidine, producing a larger-scale conformational change that affects the entire protein.
Hemoglobin can be considered as a tetramer formed by two alpha-beta dimers. The conformational change associated with the transition from T to R mainly affects the relative position of these two dimers (rather than the interactions between the alpha and beta subunits within a dimer). This is illustrated in the last stretch of the animation (drawn in black and white).
It is because of the different neurotransmitters and their receptors.
Sympathetic stimulation of arterioles in skeletal muscle is mediated by epinephrine acting on its β-adrenergic receptors.
Sympathetic stimulation of vasoconstriction occurs as a result of activation of α-1 adrenergic receptors by norepinephrine released by post-ganglionic sympathetic neurons.
Whaaat.. I don’t understand that language..
The correct answer is letter C. evaporation in the area will decrease. When humans remove vegetation from an area, the water cycle is MOST directly affected on the evaporation side. The evaporation in that area will decrease because there'll be no more plants that will hasten the evaporation process. This will create an abnormality in the water cycle.
