gas exchange occurs in the human lungs.
<span>Peter Raymond Grant, FRS, FRSC, and Barbara Rosemary Grant, FRS, FRSC, are a British couple who are evolutionary biologists at Princeton University. Each currently holds the position of emeritus professor. They are known for their work with Darwin's finches on Daphne Major, one of the Galápagos Islands. Since 1973, the Grants have spent six months of every year capturing, tagging, and taking blood samples from finches on the island. They have worked to show that natural selection can be seen within a single lifetime, or even within a couple of years. Charles Darwin originally thought that natural selection was a long, drawn out process. The Grants have shown that these changes in populations can happen very quickly.</span>
Answer:
Between days 5 and 13 of a woman's menstrual cycle, an unfertilized egg in ovary prepares its development and maturation within the follicle, while the lining of the uterus -the endometrium- progressively enlarges.
Explanation:
Under normal conditions, a woman's menstrual cycle lasts 28 to 30 days, during which time both hormonal and physiological changes occur as part of the reproductive process.
Menstruation occurs as a result of the shedding of the endometrium, which had previously developed to facilitate the implantation of a possible pregnancy. This phase usually lasts five days and is characterized by genital bleeding.
From the fifth to the 13th day, a woman's reproductive system undergoes changes in preparation for possible fertilization and pregnancy:
- <em>The unfertilized egg</em><em> is found inside the ovarian follicle, maturing before its imminent release, under the influence of follicle-stimulating hormone (FSH). The maturation of a few follicles occurs simultaneously, but only one will reach the necessary maturity to allow the release of the egg.
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- <em>The lining of the uterus</em><em>, called the endometrium, receives signals from the hormone estradiol -produced by the mature ovarian follicle- and induces proliferation and thickening of the endometrium.</em>
Approximately on the 15th day of the menstrual cycle, the egg is released and it is the time when it can be fertilized by a sperm to produce the zygote, which will start a pregnancy in women.
Learn more:
Purpose of the menstrual cycle brainly.com/question/1483249
Answer:
The correct answer is - 1/41,493
Explanation:
Let assume the frequency of the two possible same allele genotype (dominant and recessive) in an inbred population is p and q. Then the frequency of heterozygotes (H) is denoted as:
2pq + 2pqF. ( where F is the inbreeding coefficient).
The frequency of the two different hoozygotes in inbred population can be calculated as:
p2 + pqF and q2 + pqF. (Where p and q are the allele frequency of the dominant and recessive phenotype.
Given: Frequency of Alkaptonuria (q 2) = 1:500, 000
=> q = 1/707
p = 706/707 ( Approx values)
solution:
Inbreeding coefficient (F) = 1/64
Therefore,
Frequency of Alkaptonuria in second cousins= q 2 + pqF
= 1/500, 000 + (706/707 x 1/707) x (1/64)
= 1/500, 000 + 1/45, 248
= 1/41,493 (approx)
