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:
Made mostly of collagen, bone is living, growing tissue. Collagen is a protein that provides a soft framework, and calcium phosphate is a mineral that adds strength and hardens the framework. This combination of collagen and calcium makes bone strong and flexible enough to withstand stress.
This produces several negative effects on the biodiversity of the river ecosystem.
<u>Explanation:</u>
The Susquehanna river is polluted by the excess release of nutrients like phosphorous and nitrogen from agricultural land and sewage treatment plants. This can adversely affect the health of the river. The excess of nutrients will accelerate the growth of algae in the river.
The dead algae that settle at the bottom of the river decay by consuming the oxygen present in the river. This will reduce the amount of dissolved oxygen in the river and affect aquatic life.
Thick algal growth partially prevents the penetration of sunlight into the water and this affects the growth of submerged plants which are food to the fish.
<span>Answer: a. Citizens over the age of 65 use social media primarily to follow the activities of their families. </span>
<span>More than half of the citizens over 65 say that they have a social media account. They read other postings but post information about one-fifth as often as they read posts. Most of their feeds consist of posts by relatives. From this passage, we can logically say that Citizens over the age of 65 know how to use the social media and they use it primarily to follow the activities of their families. </span>