Answer:
The correct answer is - option C.
Explanation:
CFTR is a short form of cystic fibrosis transmembrane conductance regulator protein which is caused by a recessive mutation in this protein. This mutation results in the accumulation of mucus in secretory organs.
As the disease is a recessive disease, for the mutant phenotype to expressed both copies of the allele required to be recessive.
The mother is negative for the CFTR. Hence, she will not transfer the mutant allele to her child So, the child would have a wild-type phenotype even if the father having two copies of recessive allele.
Thus, the correct answer is - option C.
Answer:
The correct option is D. analogous
Explanation:
We speak of an analogy when one structure is similar to another or has the same function, but whose embryonic development and its origin or ancestor is not common, they are different, in other words, they are analogous structures if they fulfill functions or acquire similar characteristics starting from the same medium, without requiring them to have the same evolutionary origin (they may or may not be similar structurally and embryologically).
Answer:
I, II, III
Explanation:
A threshold stimulus is a stimulus that is capable to produce a response in excitable tissues such as neurons and muscle fibers. At threshold potential, the outward movement of K+ and inward movement of Na+ become equal to each other. When the potential exceeds the threshold potential, more and more Na+ enter the cell to depolarize it and to allow the opening of Na+ channels. Therefore, to fire an action potential, the threshold must be exceeded.
Conduction of action potential is all or none phenomenon which means that either it occurs or it does not occur. As an impulse is passed by each successive part of an exon, it enters the refractory period during which there is no conduction of nerve impulse. It ensures the one-way conduction of impulse from the cell body to the axon terminal only.
Answer:
make up genes and chromosomes
Explanation:
Darwin is known for his theory of evolution which explained how the organism evolved on the planet and the Mendel is known for his explanation that how the traits are passed on to the generation.
But both were unaware of this that the factors which control the traits are composed of DNA.
The DNA was discovered in 1869 in the nucleus of the white blood cells but it was not established that the genetic material is the DNA as it was discovered later in 1944. The later studies on the DNA showed that the DNA forms the genes which control the trait and are present on the chromosomes.
Thus, makeup genes and chromosomes is correct.