False.
Pain receptors are free nerve endings- nociceptors- that are stimulated by the chemical released from damaged tissue.
These receptors alert us for possible danger but they don't display sensory adaptation. Sensory adaptation it's when the response to stimulus decreases even though the stimulus is the same, we just become unaware of it.
In pain sensations, that doesn't happen.
Answer:
This question lacks options, the options are:
A) FF and ff
B) FF and Ff
C) Ff and Ff
D) Ff and ff
The answer is D (Ff and ff for parent 1 and 2 respectively)
Explanation:
This question depicts a single gene coding for fur colour in mice. The gene controls two traits, black fur and white fur, encoded by alleles F and f respectively.
According to the question, a pair of mice has been bred several times to generate the same data of 22 black fur and 23 white fur mice. Based on this data, it shows that the phenotypic ratio of black to white mice is 1:1.
To get a 1:1 phenotypic ratio of black fur offspring to white fur offspring, the parents mice must have genotypes Ff (heterozygous) and ff (same recessive alleles).
In a cross between parents Ff × ff (see punnet square), offsprings with the following genotypes will be produced: Ff, Ff, ff and ff. Ff is black furred while ff is white furred.
Ff (2) : ff (2) is equivalent to Ff (1) : ff (1).
Hence, a data of 22 black mice and 23 white mice which represents a 1:1 ratio will only be produced by parents mice with genotypes: Ff and ff.
Action potential is a mechanism of transfer of ions across the plasma membrane down their elctrochemical gradient. Action potential is regenerated by the influx of ions such as sodium in case of voltage gated sodium channels. The voltage gated channels can be either open or closed depending on the action potential. Depolarization of membrane leads to the opening of these channels that allow the sodium ions to enter the cell down their electrochemical gradient. The threshold of action potential is reached when the entry of sodium ions out reach the exit of potassium ions from the cell. This leads to the generation of action potential.
Answer:
repolarization
Explanation:
Potassium channel blockers are drugs that interfere with the flow of potassium ions (K+) through potassium channels in cell membranes, thereby prolonging the duration of the action potential (repolarization phase). For example, amiodarone is a class III antiarrhythmic agent whose target is HERG human cardiac K+ channel. This drug (amiodarone) acts by prolonging the repolarization phase of the cardiac action potential.
