<span>Because cholesterol is only minimally soluble in water (dissolves into the water at small concentrations) it needs to be transported as part of the complex with proteins-lipoproteins. Thus, lipoproteins bound by specific receptors on cell membranes. Lipoproteins, particles that transport cholesterol through the blood, contain lipid-soluble part (located inside the particle) and amphipathic or water-soluble part (one the surface of the particle). There are five types of lipoproteins: chylomicrons, very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL), low-density lipoprotein (LDL), and high-density lipoprotein (HDL).</span> <span>Receptors for the cholesterol (lipoprotein) are located on the surface of a plasma membrane and after the binding of lipoprotein, coated endocytic vesicles are formed from the surface. Those vesicles carry lipoprotein into the cell together with the receptor (internalization). After internalization, the receptors dissociate and recycle to the cell surface.</span>
Answer:
Chlorophyll molecules donate electrons to an electron acceptor in the reaction center.
Explanation:
Light reaction of photosynthesis takes place in the reaction centre. Light reaction may comprises of several proteins such as pheophytin, chlorophyll and quinones which act as light absorbing molecules.
The light reaction is the core of photosynthesis that produces ATP and NADPH to carry out the dark reaction for the production of high energy carbon molecules. During light reaction light photons are captured by photosystems such as photosystem I and II of chlorophyll in green plants. This photon cause the excitation of electron that flows through the electron transport chain from higher potential to lower potential and energy released by it is utilized for creating the gradient potential of H+ ions across the membrane. This gradient potential difference of H+ ions is used for the production of ATP through ATP synthase complex.
So chlorophyll molecules donate electrons to electron acceptors through the excitation of electrons from light photons in the reaction center.
Answer:
Each molecule of DNA is a double helix formed from two complementary strands of nucleotides held together by hydrogen bonds between G-C and A-T base pairs. Duplication of the genetic information occurs by the use of one DNA strand as a template for formation of a complementary strand.
Answer:
The correct answer would be C.10.
Krebs cycle is a part of cellular respiration that takes place in the mitochondria.
Five energy conversions take place in one complete cycle of the Krebs cycle.
These conversions lead to the formation of three molecules of NADH, one molecule of FADH₂ and one molecule of ATP.
Thus, total 10 energy conversions would occur in two rounds of Krebs cycle or when 2 molecules of acetyl-CoA go through the cycle.
The answer is Plants, as Digitalis is treated from the foxglove plant and Quinine was treated from the bark of a tree, I think it was the Cinchona tree.
