Answer: It is approximately the membrane potential at which the electrochemical gradient for Na+ is zero.
Explanation:
The charge in plasma membrane occurs with diffusion and electric fields.
For example, if there are two solutions, let's assume solution X and Solution Y are separated by a porous barrier (to diffuse in equal proportions).
The fundamental principle of diffusion states that solution from a high concentration diffuses to a lower concentration.
For instance, if the X solution contains 40 sodium ions and 40 chloride ions, the Y solution only has 30 sodium and 30 chloride ions. Due to the diffusion, these two solutions will mix and reach a steady-state.
The like charges repel, and opposite charges attract.
The bile is produced by the liver and the gallblader only serves as storage between meals. The main stimulus for the release of bile from the gallblader comes from the nervous system,after food is put in the mouth.
Answer:
A glance of earth taken from space will depict it blue. This blue colour is actually water, the major part of the earth is covered with water. We need water for almost everything, for example- drinking, bathing, cooking etc and therefore we should know about the properties of water. 65 % human body is composed of water. Water is essential for the survival of life on earth. Water is distributed unevenly on the earth’s surface. It forms a major solvent and dissolves almost every polar solute. So let us have a look at its properties.
Physical properties of water : Water is a colourless and tasteless liquid. The molecules of water have extensive hydrogen bonds resulting in unusual properties in the condensed form. This also leads to high melting and boiling points. As compared to other liquids, water has a higher specific heat, thermal conductivity, surface tension, dipole moment etc. These properties form the reason for its significance in the biosphere. Water is an excellent solvent and therefore it helps in the transportation of ions and molecules required for metabolism. It has a high latent heat of vaporization which helps in the regulation of body temperature
Chemical properties of water: Amphoteric nature:
Water can act as both acid and base, which means that it is amphoteric in nature.
Example:
Acidic Behaviour: H2O(l)+NH3(aq) ⇌ H3O+(aq)+NH+4(aq)
Basic Behavior: H2O(l)+H2S(aq) ⇌ H3O+(aq)+HS−(aq)
Redox reactions:
Electropositive elements reduce water to hydrogen molecule. Thus water is a great source of hydrogen. Let us see an example in this case:
2H2O(l)+2Na(s)→2NaOH(aq)+H2(g)
During the process of photosynthesis, water is oxidized to O2. As water can be oxidized and reduced, it is very useful in redox reactions.
Hydrolysis reaction
Water has a very strong hydrating tendency due to its dielectric constant. It dissolves many ionic compounds. Some covalent and ionic compounds can be hydrolyzed in water.
Explanation:
Answer:
The predictive value of a positive test is:
B. 18.2%
Explanation:
Answer:
TRANSCRIPTION
Explanation:
Transcription is the first process that occurs in the expression of a gene. It involves the synthesis of a mRNA molecule from a DNA template. The DNA molecule, which is located in the nucleus of an eukaryotic cell, is bound to by an enzyme called RNA polymerase in order to synthesize an mRNA molecule/strand.
RNA polymerase synthesizes a mRNA molecule using complementary base pairing rule i.e. Uracil base (U) is synthesized when Adenine (A) is read, Adenine when Thymine (T) is read, Guanine (G) when cytosine (C) is read, Cytosine when guanine is read. These nucleotide bases are then joined together via chemical bonding.
In a nutshell, RNA polymerase catalyzes the formation of a bond between the backbone sugar of one nucleotide base to the backbone phosphate of another nucleotide base in the metabolic process of TRANSCRIPTION.
