Answer:
The study of DNA started much before the discoveries of Rosalind Franklin and Maurice Wilkins. Nucleus of cell was discovered by Robert Brown in 1831 but the material present inside the nucleus called "nuclein" (DNA) came from the studies of Johann Friedrich Miescher in 1869.
Explanation:
The complete question is:
If these organisms were arraigned in a food pyramid, which organism would have the least amount of total energy available?
- Producers
- Carnivore
- Herbivores
- Top predators
Answer: Top predators
Explanation:
The top predators get the least energy because according to the 10 per cent law the energy transfer only 10 energy is transferred to the next successive level.
The next level of the organism receives only 10 of the total energy that the previous level has.
Hence, the top predators have the least amount of energy in it as the energy is transferred through various levels before reaching top predators.
Answer: The answer is C.
C. They're examples of cell organelles.
Explanation: I just looked up the question and I got that answer.
Complete question:
The endplate potential (EPP) at the frog neuromuscular junction occurs because ACh simultaneously increases the conductance of the postsynaptic membrane to Na and K
Answer:
TRUE
Explanation:
The Acetylcholine neurotransmitter is released from the presynaptic cell by the process of exocytosis.
Once the molecule is in the intercellular space, it moves forward the postsynaptic membrane to join its receptor in the motor plate.
Once the joining has occurred, the receptor acquires a channel shape allowing the ion transference that will make possible the modification of the action potential. Ions traffic will consist of the pass of sodium and calcium to the interior of the cell and potassium to the exterior. Quantitatively, the interchange Na-K is the most significant.
K+ follows a concentration gradient, while Na+ follows an electrochemical gradient. The interchange results in an increase of positive charges in the interior of the muscular cell.
Whenever there is a sufficient number of Acetylcholine receptors are active, the depolarization threshold of the motor endplate is exceeded. This activates an action potential that extends to the rest of the muscle membrane.
Answer:
The way I would separate the shell fragments from the sand would be by using a filter. As shell fragments are larger than sand. So I would use a filter with 2 mm spaces to separate them. Now, for the sand separation from the water, I would heat the water so it would evaporate and connect a tube to another recipient making the sand stay in the first tube and the water vapor cools in the tube to precipitate in the other recipient. Three mixtures I have prepared at home are chocolate milk, coffee and cream, and lemon juice and tea.
Explanation:
To understand this answer we have to remember a few things. First, mixtures always have solute and solvent. The solvent is the most liquid component of the mixture and it can incorporate the more solid element in its composition to carry it. Now, there are several methods to separate them, barrier methods like filters are the first and more basic ones, as they are aimed to separated big solutes. While evaporation can be used to separate two very liquid elements. Like distillation of alcohol to separate the most concentrated oil from the alcohol.