Selective breeding
In selective breeding, the
desired genes from one organism are combined with genes of another
organism, resulting in a new combination of genes.
The selective breeding is quite voluntary and is not necessarily natural or congenital. It is the act of how people or individuals can choose traits in the gene pool of their choice to produce their desired or goal organism in the process. This trait is influenced in the host of the specific sperm and egg cell which makes up the chromosomes.
Answer:
thermodynamically unstable but kinetically stable.
Explanation:
The complete question is as follows:
Under physiological conditions, peptide bond formation and degradation both require enzymes, but only formation requires coupling to GTP hydrolysis. Based on this information, peptide bonds under physiological conditions are:
A. both thermodynamically and kinetically stable.
B.thermodynamically unstable but kinetically stable.
C.thermodynamically stable but kinetically unstable.
D. both thermodynamically and kinetically unstable.
- The term thermodynamically unstable refers to the fact that the peptide bonds are prone to breakage under physiological conditions.
- The reason why one can conclude the thermodynamic instability of the peptide bonds under physiological condition is that there is a need for a source of energy i.e. GTP hydrolysis for the formation of the peptide bond.
- The fact that the breakage of peptide does not require any input of energy but the only formation does confirms the fact that under physiological conditions they are thermodynamically unstable.
- Even though they are thermodynamically unstable, they are kinetically stable because both the formation and degradation require enzymes.
- The function of enzymes is to decrease the activation energy and hence, increase the rate of reaction. This means that if the enzymes are absent the rate of breakage of peptide bonds would be really slow this points out to the fact that they are kinetically stable under physiological conditions.
Answer: Bundles of axons in the central nervous system are called a "tract"
Explanation:
Axons(nerve fiber) consist of long slender projection of neurons or nerve cells that conduct and transmit impulses away from the neuron or nerve cell body. Axons are surrounded by endoneurium layer which contain protein fluid that surround each axon.
Bundles of axon in the CNS is known as tract. We have ascending tracts and descending tracts. The ascending tracts function are to conduct and carry impulses along the spinal cord to the brain while the descending tracts transmit and carry the impulses from the brain to lower regions (downward) of the body. Tracts are identified by their origin (where the bundle start) and also the end/termination of axon bundle.
The largest tracts are fasciculi gracilis and cuneatus which are known as ascending tracts.