Answer:
The correct answer is - she is heterozygous for a mutated BLM allele and will have an increased risk of colon cancer.
Explanation:
Autosomal recessive disease expresses itself in next-generation only if there is both alleles are recessive for the gene. In haploinsufficiency, the dominant allele fails to express itself in the phenotype due to insufficiency. So, if even one allele of the recessive gene present in the haploinsufficiency case, it will affect and express its trait.
She is heterozygous for a blood syndrome, as her mother had but her father has no disease, allele and will have an increased risk of colon cancer.
Human height is one of the traits that belong to traits that cannot easily be placed in discrete phenotypic classes (there is not only tall and short people, there is continuous variation of height between them). Such traits are usually controlled by more than one gene (polygenic traits).
On the other hand, a Mendelian trait is controlled by a single locus.
Natural selection is the process by which individuals with characteristics that are advantageous for reproduction in a specific environment leave more offspring in the next generation, thereby increasing the proportion of their genes in the population gene pool over time. Natural selection is the principal mechanism of evolutionary change, and is the most important idea in all biology. Natural selection, the unifying concept of life, was first proposed by Charles Darwin, and represents his single greatest contribution to science.
Natural selection occurs in any reproducing population faced with a changing or variable environment. The environment includes not only physical factors such as climate or terrain, but also living factors such as predators, prey, and other members of a population.
Mechanism of Natural Selection
The mechanism of natural selection depends on several phenomena:
• Heredity: Offspring inherit their traits from their parents, in the form of genes.
• Heritable individual variation: Members of a population have slight differences among them, whether in height, eyesight acuity, beak shape, rate of egg production, or other traits that may affect survival and reproduction. If a trait has a genetic basis, it can be passed on to offspring.
• Overproduction of offspring: In any given generation, populations tend to create more progeny than can survive to reproductive age.
• Competition for resources: Because of excess population, individuals must compete for food, nesting sites, mates, or other resources that affect their ability to successfully reproduce.
Given all these factors, natural selection unavoidably occurs. Those members of a population that reproduce the most will, by definition, leave more offspring for the next generation. These offspring inherit their parents' traits, and are therefore also likely to succeed in competition for resources (assuming the environment continues to pose the same challenges as those faced by parents). Over several generations, the proportion of offspring in a population that are descended from the successful ancestor

Uloborid spider eggs and spiderlings. In any given generation, populations tend to create more offspring than can survive to reproductive age.
increases, and traits that made the ancestor successful therefore also increase in frequency. Natural selection leads to adaptation, in which an organism's traits conform to the environment's conditions for existence.
Answer :B. By changing the shape of the enzyme's active site.
check the attachment
Explanation: This is a type of inhibition , in which a molecule binds to another part of the enzyme instead of the active site.
On binding, it disrupts the normal hydrogen bond and hydrophobic interactions holding the enzyme molecule in its three dimensional shape, therefore distorting the conformation and ACTIVE SITE of the enzyme (changed it shape).
Since the active site is the precise location enzyme must bind with substrates for enzymatic reactions,this makes the enzyme not fit for binding with the substrate, therefore the efficiency is reduced. No substrate-enzyme complex, and hence no substrate-product complex for the release of products, this brings down the turnover rate and eventually
<u>the rate of reaction of the enzyme</u>
Thus, the enzyme function is totally blocked, even in high concentration of the substrate,
Answer:
Gradually, as generations of elephants continued to selectively use and develop their trunks.
Explanation:
Jean-Baptiste Lamarck was famous French Naturalist. He was a soldier, a biologist and an academic. He gave an early theory of evolution known as the theory of Lamarckism.
It was Lamarck who first believed that elephants earlier had small trunks. But eventual when there was scarcity of food and water, the elephants stretched out its trunk to reached out for food such as trees and also water. And as a result their offspring inherited long and powerful trunk.
In his theory of Lamarckism, he believed that the species passes on its traits to the offspring which they acquired through their use in their lifetime. In this case, the elephants might have used their trunks in such a way that they became long and strong over time and they passed tis trait to their babies.
