Answer:
This question lacks options, the complete question is: What do you think would have the greatest effect on the body—a harmful mutation in a pluripotent embryonic stem cell, or a harmful mutation in an adult multipotent stem cell?The correct answer is a harmful mutation in a pluripotent embryonic stem cell.
Explanation:
Pluripotent Stem Cells can self-renew and differentiate into any of the three germ layers, which are: the ectoderm, the endoderm and the mesoderm. These three germ layers subsequently differentiate to form all the tissues and organs within a human being. If during embryonic development, genetic mutations - alterations in genes - occur in the embryonic stem cell, they pass to daughter cells as a consequence of cell division, and an individual is generated whose cells differ at the genetic level. Multipotent stem cells are organospecific cells, that is, they can give rise to any type of cells but from a specific organ (a lung, a kidney or the brain). Their differentiation ends the moment they specialize and become a cell with a specific function within a specific tissue or organ. If there were a mutation in these cells, it would damage a specific designed tissue or organ.
<span>Anton van Leeuwenhoek learned to grind lenses ( 1668) and develop simple microscopes.
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Leeuwenhoek heated the middle of a small soda glass rod , over a flame. On pulling apart the two ends, the glass rod elongated into thin whiskers .
Heating the end of this whisker resulted in a tiny high quality glass sphere. These glass spheres then became the lens of his microscope, with the smallest sphere providing the greatest magnification.
Leeuwenhoek's designs were very basic. The body of the microscope was a single lens mounted in a tiny hole on a brass plate. The specimen was then mounted on a sharp point that sticks up in front of the lens. It's position and focus could be adjusted by turning the two screws.
The entire instrument was about 3 to 4 inches long and had to be held up close to the eye, requiring good lighting and great patience to use.
Answer:
The probability of obtaining a "goober" butterfly is 6.25%
Explanation
If there are three possible combinations of butterflies, with yellow and blue being dominant, green is supposed to contain a recessive pattern, so according to Mendel's law of character independence, the pattern RR and BB manifest the dominant phenotype yellow, blue or yellow and blue in spots, the green pattern must be recessive is represented by the letter a, the punnett graph is made, obtaining that 56% present a dominant pattern, 37.5% will be spotted and the pattern recessive must match to generate 6.25% of butterflies “goober”.
Answer:
Testes and ovaries produce two types of hormones:
androgens (male sex hormones)
estrogens (female full hormones)
In each type of gland, both types of hormones are secreted only in different amounts: the ovaries secrete more estrogen than the androgen hormones, and the sperm inversely.
Explanation:
In testicular tissue, Leydig cells produce androgen hormones: androsterone and testosterone. The ovaries produce a group of estrogen hormones and progesterone. These hormones exert their effect at puberty when the glands are activated. At puberty, the pituitary gonadostimulins activate the sex glands, whose activity leads to the development of secondary sex characteristics (the appearance of first menstruation in girls, beards and mustaches in boys, etc.).
