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TiliK225 [7]
3 years ago
9

Which of the following make up a nucleotide?

Biology
1 answer:
soldi70 [24.7K]3 years ago
4 0

Answer:

adenine, guanine, thymine, or cytosine

Explanation:

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The leader of the skirmish against Chitto Harjo and other resistance leaders was US Marshal __________
Sidana [21]
U.S. Marshal Leo Bennett was the leader of the Skirmish against Chitto Harjo and other resistance leaders . When delegations of Snakes started seizing property and whipping tribe members who supported allotment, the Creek National Council turned to U.S. Marshal Leo Bennet to arrest Harjo and his followers. 
5 0
3 years ago
16. The substances that are reabsorbed did not diffuse (move) from the nephron bowl into the
SpyIntel [72]

Answer:

Active transport.

Explanation:

The kidney uses active transport  to move these substances from the nephron to the  renal vein because these substances did not moves from the nephron bowl to the renal vein through simple diffusion so for this purpose active transport is used in which energy is spent in order to move the substances from one region to another so we can say that kidney must use active transport to move reabsorbed substances from the nephron to the  renal vein.

4 0
3 years ago
Consider a species of sparrow that originally lived only in Alaska but recently expanded its range through North America, then C
Shtirlitz [24]

Answer:

North America is the one with the highest heterozygosity frequency for most loci, followed by Central America, and finally, South America with the lowest heterozygosity level.  

Explanation:

Some different forces or mechanisms might alter H-W equilibrium and lead to evolution, such as mutation, natural selection, migration, and genetic drift.

In the exposed example, we have a species of sparrow that migrates from Alaska to North America. Migration is unidirectional, which means that the movement occurs in only one direction: from Alaska to North America. We should also consider that the first immigrants colonized the area for the first time, meaning that there was not a receiving population of the same species already established. Finally, we need to consider that Alaska´s environmental conditions are very different from North America´s environmental conditions.

When a species arrives at a new place, it needs to adapt. The establishment and dispersion of the species in the new area depend on previous adaptation. So, when the firsts sparrow individuals arrived in North America, they faced new environmental conditions that acted as selective pressures that drove to the occurrence of mutations. A mutation implicates a stable and inheritable change in the genetic material. A mutation introduces changes, new alleles in the population, variability. But mutation rates are very low and have no evolutive direction, so they need another force to increase or decrease the mutant allelic frequencies. Natural selection benefits new advantageous alleles and transmits them to new generations changing their relative frequencies. <em>So, sparrows arrive in North America, mutated, and natural selection favored the beneficial mutations leading to a better adaptation to the environment.</em> This means that the heterozygosity level in this new recent population is very high.

As animals adapt to the new habitat and have better dispersal genes, they get to disperse even more. So they start new migration south, to Central America and South America. Again, they are moving to new regions with new conditions, and to establish they need to suffer new adaptations. But remember that we are talking about a recent event in time. Probably the animals migrating south are just a few.  They have not spent enough time yet in the new area, to adapt to the new environment and to include new genes into their population. What is even more, as they are a small new population moving south, they are more vulnerable to genetic drift events. Genetic drift acts on a population decreasing the variability between individuals, hence, decreasing the heterozygosity. <em>This small population suffers low mutation, has not enough time to establish, and is more vulnerable to genetic drift events.</em> The heterozygosity level is probably inferior to North America´s one.

Comparing the three areas, we could say that North America is the one with the highest heterozygosity frequency, followed by Central America, and finally, South America with the lowest level of heterozygosity.

8 0
2 years ago
Which of the following is true regarding units of geologic time?
Katarina [22]
d. Eras are divided into periods; periods are divided into epochs. The geologic time is divided from the largest defined unit of time called supereon, which is composed of eons. Eons are further subdivided into eras, periods, epochs and the smallest unit of time - ages.
6 0
3 years ago
Read 2 more answers
A remote-controlled helicopter flew 826 meters west at a constant velocity. It flew that
frosja888 [35]

Explanation:

Distance = 826m

time = 70second

velocity = distance/ time

v = 826/70

v = 11.8m/sec

5 0
2 years ago
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