BV
Beatriz Valdespin
Answers (6)
BV
Answered
Which of the following statements concerning the embryonic cardiovascular system is true?
A) The heart develops from four endothelial tubes.
B) Blood vessels form from blood islands.
C) An opening in the interatrial septum is called the sinus venosus.
D) The bulbus cordis becomes the sinoatrial node (the adult pacemaker) .
E) There is an opening in the interventricular septum.
A) The heart develops from four endothelial tubes.
B) Blood vessels form from blood islands.
C) An opening in the interatrial septum is called the sinus venosus.
D) The bulbus cordis becomes the sinoatrial node (the adult pacemaker) .
E) There is an opening in the interventricular septum.
On Jul 10, 2024
B
BV
Answered
The bacterium that causes botulism disease is harmless until it:
A) is infected by prions.
B) is infected by lytic bacteria.
C) is irradiated by UV radiation.
D) contains a certain prophage DNA.
E) is infected by certain retroviruses.
A) is infected by prions.
B) is infected by lytic bacteria.
C) is irradiated by UV radiation.
D) contains a certain prophage DNA.
E) is infected by certain retroviruses.
On Jul 07, 2024
D
BV
Answered
Why does the evaporation of sweat effectively cool the body?
A) As sweat cools, the distance between water molecules increases, which further reduces the temperature.
B) Since evaporation requires energy to overcome cohesion, heat energy is removed from the body surface.
C) Water in sweat insulates the skin and absorbs heat from the body before evaporation.
D) Water absorbs heat from skin oils, which is removed from the body during evaporation.
E) Breaking the bonds holding water molecules together releases energy, which is absorbed by the solutes present in sweat.
A) As sweat cools, the distance between water molecules increases, which further reduces the temperature.
B) Since evaporation requires energy to overcome cohesion, heat energy is removed from the body surface.
C) Water in sweat insulates the skin and absorbs heat from the body before evaporation.
D) Water absorbs heat from skin oils, which is removed from the body during evaporation.
E) Breaking the bonds holding water molecules together releases energy, which is absorbed by the solutes present in sweat.
On Jun 10, 2024
B
BV
Answered
Describe how parasites may exert negative frequency-dependent selection on their hosts.
On Jun 06, 2024
Parasites can exert negative frequency-dependent selection on their hosts by targeting the most common host genotypes. This means that as a particular host genotype becomes more common within a population, it becomes a more attractive target for the parasite. As a result, the fitness of the common host genotype decreases, leading to a decrease in its frequency within the population. This creates a dynamic where less common host genotypes have a selective advantage, as they are less likely to be targeted by the parasite. This can lead to a more diverse host population, as less common genotypes are favored by negative frequency-dependent selection. Overall, this can have a stabilizing effect on the host population, preventing any one genotype from becoming too dominant.
BV
Answered
For signatory countries to the WTO, quotas limiting imports are considered a trade barrier and therefore should be minimized or eliminated.
On May 10, 2024
True
BV
Answered
The egg from a ________ has been observed to form a gray crescent after fertilization.
A) fish
B) frog
C) reptile
D) chicken
E) human
A) fish
B) frog
C) reptile
D) chicken
E) human
On May 07, 2024
B