This describes standards that apply to good clinical practice relative to clinical trials involving human subjects or health products used by humans. ICH stands for International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use. ICH brings together regulatory authorities and pharmaceutical industry. E6 was a series of guidelines to ensure good clinical practice (GCP).
Answer:
In muscles contraction the correct order of the steps are: A (Nerve impulse reaches the muscle), B (Action potential travels down T-tubules), C (Calcium binds to troponin), D (Tropomyosin moves).
Explanation:
Skeletal muscle contractions are based on different physiological and biochemical phenomena that happen in every cell. These phenomena are due to stimulation produced by somatic motor neurons, which axons get in contact with muscle fibers through a neuromuscular synapse. In rest, attraction strengths between myosin and actin filaments are inhibited by the tropomyosin. When an action potential is originated in the central nervous system, it travels to the somatic motor neuron membrane: the muscle fiber, and activates the calcium channels releasing it in the neuron. Calcium makes vesicles to fuse with the membrane and release the neurotransmitter named acetylcholine (Ach) into the synaptic space in the juncture. Then, Ach binds to its receptors on the skeletal muscle fiber. This causes the ion channels to open, and positively charged sodium ions cross the membrane to get into the muscle fiber (sarcoplasm) and potassium get out. The difference in charges caused by the migration of sodium and potassium makes the muscle fiber membrane to become more positively charged (depolarized). The action potential caused by this depolarization enters the t-tubules depolarizing the inner portion of the muscle fiber. This activates calcium channels in the T tubules membrane, that make the calcium be released into the sarcolemma. At this point, tropomyosin is obstructing binding sites for myosin on the thin filament. When calcium binds to the troponin C, the troponin T alters the tropomyosin by moving it and then unblocks the binding sites. Myosin binds to the uncovered actin-binding sites, and while doing it ATP is transformed into ADP and inorganic phosphate. Z-bands are then pulled toward each other, thus shortening the sarcomere and the I-band, and producing muscle fiber contraction.
Let us consider each statement separately. A zygote is the result of the fusion of two gametes (reproductive cells) and thus only appears in sexual reproduction. For the same reason, E) is wrong; meiosis is a step in the making of gametes and again, a plant that reproduces asexually does not produce gametes. B) is also wrong since (healthy) members of the same species have the same number of chromosomes. The leaf cells of the daughter plant will have 24 chromosomes. The only case where this would not hold, is the case of sexual reproduction, where the gametes of the new organism have half the chromosomes of the ancestor organisms. Hence, C and D are correct. We have already justified D. As far as C is concerned, in asexual reproduction we have that every organism passes his whole genome to his offspring and this creates a lot of clones next to each other. Every plant in a garden of a species that reproduces asexually may be genetically identical and some biologists consider them for that reason as the same organism!
Answer:
The process of dissolving is endothermic when less energy is released when water molecules “bond” to the solute than is used to pull the solute apart. Because less energy is released than is used, the molecules of the solution move more slowly, making the temperature decrease.
Explanation:
Is temperature decrease endothermic or exothermic?
Image result for A substance is dissolved in water, and the temperature of the surroundings decrease. Is this process endothermic or exothermic?
There are two methods for distinguishing between exothermic and endothermic reactions. When energy is released in an exothermic reaction, the temperature of the reaction mixture increases. When energy is absorbed in an endothermic reaction, the temperature decreases.
