Answer: 1/16, or approximately 6.25% (see explanation below)
Explanation:
Answering this question requires two steps.
First, we need to figure out the probability that this couple will have a child with albinism in the first place. We know the following:
- Both parents are unaffected.
- The couple has already had one affected child.
- Albinism follows an autosomal recessive inheritance pattern.
Let ( M = normal gene ) and ( m = mutated gene ). Since the condition is recessive, the affected child can be assumed to have a “mm” genotype. Barring the possibility of a de novo mutation (which are assumed to be rare), the affected child must have inherited one ”m” allele from each parent. Since both of them are unaffected, however, we can assume that they are both carriers (genotype “Mm”). In conclusion, 1/4 of their offspring (25%) <em>for any given pregnancy</em> may be expected to have albinism. See the resulting Punnett square:
<u> | M | m </u>
<u>M | MM | Mm </u>
<u>m | Mm | mm </u>
Note that the question asks about the probability that not one but two consecutive births result in affected children. Since it can be assumed that both events are independent (meaning: the outcome of a pregnancy does not influence the outcome of following ones), we may apply the rule of multiplication for probabilities. The final answer is therefore 1/4 * 1/4 = 1/16.
Answer:
The correct answer is case control study.
Explanation:
A study in which a comparison is made between the patients carrying the disease with the patients not carrying the disease is known as the case-control study. In the mentioned study, the one carrying the disease is termed as cases, and the one that does not possess the disease is termed as controls.
This form of study is generally done to predict the association between the disease and the risk factor. In case-control studies, only observation is done as no attempt is made to change the course of the condition. The prime objective of the study is to predict the exposure of the risk elements for the individuals present in two groups, that is, controls and cases. This form of study is also called case-referent studies or retrospective studies.
Answer: Rheumatoid arthritis
Explanation:
Rheumatoid arthritis is a disease which is a autoimmune disease which is usually associated with the pain and inflammation in the joints. This is the condition in which the person is not able to walk or sit for a longer period of time as it is painful.
The lysosomes is an enzyme that is found in the saliva and tears of human beings which helps in the degradation of the cell wall.
In case of autoimmune diseases the antibody present in the body destroys the cells of the body considering it as self antigen. Its concentration is found high in the people suffering from this autoimmune disorder.
Plants use the sun to produce food then animals eat the plants for food
Complete question:
Two species of closely related frogs are found in the same pond high in the Andes of South America. Both species only have teeth on the top jaw. One has small teeth for holding small live prey prior to swallowing. The other species has very large sharp teeth for injuring and killing large prey prior to biting off pieces of flesh for consumption. The above is an example of:
- Directional selection
- Analogous structures
- Character displacement
- Hybridization
- Vestigial structures
Answer:
Explanation:
Competition is an ecological and evolutive process very common in nature. Competition might be intra- or interspecific. Competition between different species in a community or ecosystem might be due to the same resource use, or the same territory, shelter, etcetera. When a resource is useful for two or more species, and limited, they compete to gain it.
The principle of competitive exclusion states that different species with the same requirements sharing the niche can not coexist indefinitely based on the same limited resource. When <u>two competing species coexist, this is because of niche partitioning or niche differentiation</u>.
Differentiation of effective niche is closely related to <u>character displacement.</u>
<u>Character displacement</u> is the result of interspecific competition, in which two or more species that live in the same habitat manage to avoid competition by developing different traits. Morphological divergence, or any adaptative trait development, fixated genetically, is the product of niche segregation. Species tend to differentiate morphologically in the presence of strong competitors. Traits divergence favors coexistence in the same place.
In the exposed example, both species live in the same pond. But to avoid competition and competitive exclusion, species developed different teeth sizes to feed on different prey items.
