All categories

3 years ago

Environmental factors can influence natural selection because they can increase or decrease

Biology

1 answer:

timama [110]3 years ago

3 0

Answer:

the amount of genetic variation in a population.

Explanation:

The proportion of the members of a population possessing beneficial allele due to natural selection will increase with time while the proportion of those possessing a harmful allele will decrease with time. After many generations, all the members carrying the harmful allele will die out leaving only those with the beneficial allele. The result is a genetic variation of the population with time.

You might be interested in

Often, the second part of a scientific name is (1 point)

lyudmila [28]

A. a description of a trait or habitat.

8 0

4 years ago

1. List the distances between each pair of genes:

user100 [1]

Answer:

20MU

16MU

4MU

2.Beak color and tail feather length

3.Tail feather length and feather color

RESPECTIVELY

Explanation:

Distance between beak color and tail feather length is 20 MU

Distance between beak color and feather color is 16MU

Distance between tail feather length and feather color is 4MU

2.Beak color and tail feather length are the two most farthest alleles

3.Tail feather length and feather color are the closet alleles

6 0

3 years ago

1. The point in the Moon's orbit when it's farthest away from the Earth is called

romanna [79]

1.C | 2.D | 3.B | 4.D

---

1. The point in the Moon's orbit when it's farthest away from the Earth is called apogee. On the contrary, the perigee is the point in the Moon's orbit when it's the nearest from the Earth. Those points are very important for tides and other natural phenomenon such as eclipse and in general for the observation of the skies.

---

2. Gamma rays are a type of electromagnetic radiation cannot be focused. They diffuse from the emission points until there is an object that stops them. This is the reason why when you have to use gamma rays, you are in other rooms, in order to prevent the radiation to go through them.

---

3. The corona it's the outermost layer of the Sun's atmosphere. It's also the part where most of the activity of the sun that we can see take places. It's a subject that has fascinating scientists for centuries and only recently we are studying in more details this interesting and weird place, due to the advancement of technology.

---

4. Tides are a result of the gravitational attraction of the Sun and Moon. The Earth, the Sun and the Moon have masses and their own gravities. The interactions between these corps causes tides movement on Earth that are fundament to life on the planet, because they are a fundamental part in the cycle of water and air.

4 0

3 years ago

Read 2 more answers

Please help!!<br>What are some factors that influence emotional changes throughout adolescence?

Svetradugi [14.3K]

Answer:

Explanation:

Some of the factors that influence emotional changes during adolescence include, among others, changes in self-perception, changes in the way teens are treated, increased sensitivity to criticism, increased desire for independence, and an increased need to belong.

4 0

3 years ago

A person with a genotype of HbSS has sickle cell disease. A person with a genotype of HbAS allele carries the sickle cell trait.

Mariana [72]

Answer:

There is a 25% chance that the offspring will have sickle cell anemia (SS)

Explanation:

Sickle cell anemia is a genetic disease, where red blood cells can take the shape of a crescent (sickle), and this change allows the red blood cells to be more easily destroyed, causing anemia. Sickle cell anemia is caused by defective hemoglobin (Hb), which is the oxygen carrying protein in blood cells. Hemoglobin is made up of four peptide chains, each bound to a heme group. Different hemoglobins have different combinations of these chains. Hemoglobin A (HbA) is the primary hemoglobin affected in sickle cell, because their beta-globin chains end up misshapen because of a genetic mutation in the beta-globin gene. Sickle cell anemia is an autosomal recessive disease, so there needs to be a mutation in both copies of the beta-globin gene in order to get the disease. If a person has just one copy of the mutated gene and the other copy is normal for the gene, then they are a sickle cell carrier.

So first of all, this looks like a dihybrid cross, but it is not because we are dealing with one pair of alleles (gene that causes sickle cell), so we will actually be doing a monohybrid cross.

So let’s go through the alleles step by step:

Hb = hemoglobin (constant, all red blood cells have hemoglobin, we are looking at the mutation in the beta globin gene of the hemoglobin which will be the allele we focus on)

SS = sickle cell (mutated beta globin gene (S) x 2)

AA = normal beta globin gene (A) x 2 (no sickle cell)

AS = carrier (one sickle cell gene + one normal gene)

HbAS x HbAS

Carrier x carrier

PARENTS A S

A AA AS

S AS SS

25% chance that the offspring will have a normal (does not have sickle cell anemia) genotype (AA)

50 % chance that the offspring will be carriers (AS)

25% chance that the offspring will have sickle cell anemia (SS)

4 0

3 years ago

Read 2 more answers