Answer:
Chemotaxis is the directed migration of cells in response to concentration gradients of extracellular signals. ... In multicellular organisms, it ensures that the right cells get to the right place at the right time during development, and plays an essential role in processes such as wound healing and inflammation [2, 3].
A trait is a distinct variable of
a character of an organism
that can be inherited. Which
of the following would be
considered a trait?
A. skin tone
B. eye color
C. green eyes
An experiment similar to the 1952 Hershey and Chase experiments was done in which radioisotope 35S was added to a bacteriophage replicating within its bacterial host. The new phage particles were carefully isolated and used to infect fresh bacterial cells and no radioisotopes were utilized. Based on this information, where would you expect to find the 35S radioisotope immediately after infection
Answer:
inside the phage ghosts outside the bacterial cells.
Explanation:
According to Hershey & Chase- Experiments, the radioisotope 35S is frequently associated with protein since sulfur is a protein component. The radioactive sulfur is absorbed into the protein coat because it already contained sulfur (35S). The radioactive marker 35S was integrated into the Bacteriophage protein coat and remained as phage ghosts outside the bacterial cells.
Plasma estrogen levels reach their peak at the end of the luteal phase of the ovarian cycle.
a. True
b. False
Answer:
Plasma estrogen levels reach their peak at the end of the luteal phase of the ovarian cycle.
a. True
Explanation:
A woman's estrogen levels become highest towards the end of her ovulation. At this point, the woman is naturally prepared for a possible pregnancy. The occurrence of the highest estrogen levels coincides with the luteal phase, a stage of a woman's menstrual cycle, which occurs after ovulation (or the release of eggs from the ovaries), and before the start of the normal period. This luteal phase has been observed to be within 14 days for all women. By the end of the luteal phase, the corpus luteum function declines.
b) What is DNA? What is a Gene?
Why do so many more people have brown eyes then blue eyes
Several human populations spread throughout the Sahara desert have multiple mutations in Gene R that confers heat tolerance. Independently, a small population of humans in the Mojave desert of California have a unique mutation in Gene Z that also confers heat tolerance. The evolution of adaptation of heat tolerance across all of these populations would be considered an example of _________
Answer:
Variation
Explanation:
Migration into a population from other populations with varying gene frequencies, evolution, or adaptation of heat tolerance is a cause of variation. The allele frequency of the resulting hybrid population would be right in the middle of its original value and the donor population's frequency. In tropical and subtropical ecosystems (Sahara deserts), high temperatures are a significant restriction to human population productivity; they induce morphological and physiological modifications at all times, resulting in significant yield losses but the ability and evolution of human species to cope in this region is as a result of variation.