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).
Answer:
D) Asexual reproduction produces offspring that are genetically identical to the parent.
Explanation:
I am honestly not quite sure of this answer, but I was trying to read up on the topic and this is the answer I'm most confident in. It would make sense that the offspring are genetically identical to the parent because they would have no where else to get their genes/mix to form new ones. I really hope this helps!
No, the vast majority of DNA mutations are not physically noticeable, and those that are noticeable physically are mainly cosmetic differences, such as a change in hair color, or heterochromia.
The seed.
I think...
Go look at some memes~
Out of the choices given, the excerpt that best reflects Byron's appreciation of beauty was "the nameless grace/Which waves in every raven tress." The excerpt comes from the poem "She Walks in Beauty."
