The train traveled 100km (50x2) down and then 375km (75x5) up. So the train is 275km (375-100) up from where it started.
Answer:
The correct option is BLOOD CALCIUM LEVEL.
Explanation:
The options attached to this question are given below:
A. Filtration membrane integrity
B. Systemic blood pressure
C. Blood calcium level
D. Renal artery/arteriole diameters
Kidney is an excretory organ, which functions by filtering waste products out of the blood. The rate at which the kidneys filter the blood depend on some factors; such factors include: water intake, systemic blood pressure, vasoconstriction, dehydration, filtration membrane integrity etc.
Blood calcium level does not have any effect on the rate at which the kidneys filter the blood.
<span>Some mutations don't have any noticeable effect on the phenotype of an organism. This can happen in many situations: perhaps the mutation occurs in a stretch of DNA with no function, or perhaps the mutation occurs in a protein-coding region, but ends up not affecting the amino acid sequence of the protein.</span>
Answer:
Species separated by a physical barrier for a long time, suffer allopatric speciation, so they can not interbreed anymore.
Explanation:
Allopatric speciation consists of the geographic separation of a continuous genetic background giving place to two or more new geographically isolated populations. These separations might be due to migration, extinction of geographically intermediate populations, or geological events. In this speciation, some barriers impede genetic interchange, or genetic flow, as the two new populations that are separated can not get together and mate anymore. These barriers might be geographical or ecological.
Vicariance is the geographical separation of an original population into two or more new groups. Discontinuities in the physical environment like rivers, mountains, water, etc., are physical barriers that impede genetic flow between the separated groups.
The process of allopatric speciation involves different steps:
- The emergence of the barrier.
- Interruption in the genetic interchange
- The occurrence of new mutations and their accumulation in time in each population. Slow and gradual differentiation.
- Genetic divergence by natural selection and reproductive isolation makes it impossible for the two groups to mate even if the barrier disappears.
- Prezigotic isolation mechanisms favored by selection once occurs a secondary contact between the new species in formation.
I think the answer is D but it's been a while since I've done this.
