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Serga [27]
3 years ago
7

What must happen before a chemical reaction can begin?

Biology
2 answers:
Nitella [24]3 years ago
3 0
The answer should be <span>The activation energy must be reached.</span>
ankoles [38]3 years ago
3 0

Answer:

The reactants need to reach activation energy.

Explanation:

For a chemical reaction there need to be:

1.- The reactants ( the elements or compounds that are going to react).

2.- The activation energy (the necessary energy to start changing the matter in the interchange of atoms among the reactants).

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The diagram below shows four positions of the Moon. Which position produces the highest possible tides?
Nookie1986 [14]

Answer:

Full moon and New Moon

7 0
3 years ago
What did emile durkheim say about social deviance?
stiks02 [169]
<span>The reaction to it promotes social unity.</span>
8 0
3 years ago
Read 2 more answers
A locus that affects susceptibility to a degenerative brain disease has two alleles, V and v. In a population, 16 people have ge
Pie

Answer:

Yes, the population is evolving

Explanation:

Hardy-Weinberg equilibrium states that a population is not evolving if it is in hardy weinberg equilibrium as the alleles frequency do not change over time in generations.

In mathematical equation, the genotype frequency will be -P²+2Pq+q²=1 and allele frequency will be p+q=1, where p = dominant allele and q will be recessive allele.

In the question, since the observed genotype are-

P² - VV= 16

2Pq- Vv- 92

q²- vv- 12

<u>1. Calculate allele frequency</u>

Now we will calculate if the expected value is same or close or not.

We will calculate allele frequency

Population has 120 individuals which means it has - 240 alleles.

In which V (p) will be- 32 +92= 124 allele

p- dominant allele/ total allele=  124/ 240 = 0.52

P= 0.52

q will be 1-0.52= 0.48

<u>2. Expected genotype frequency</u>

Now we will calculate expected genotypic frequency.

P²- 0.52 X 0.52= 0.27

2Pq = 2 x 0.52x 0.48 =  0.5

q²= 0.48 x 0.48 =  0.23

<u>3. Expected progeny </u>

P²= 0.27 x 120= 32 VV

2Pq= 0.5 X 120= 60 Vv

q²= 0.23 x 120= 28 vv

Since the observed value is not equal to the expected value therefore the population is not in Hardy- Weinberg equilibrium and the population is evolving.

Thus, Yes, the population is evolving is correct.

4 0
4 years ago
Read 2 more answers
Where is the pigment in plants found?
Iteru [2.4K]

Answer:

The chlorophylls, a and b, are the pigments of photosynthesis. They are produced in chloroplasts in the photosynthetic tissues of the leaf. The chlorophyll molecules are very water repelling, partly because of the long phytol tail in the molecule.

7 0
3 years ago
Aniridia, a type of blindness, occurs in humans and is due to a dominant allele, A. Normal vision is due to the allele, a. Migra
ddd [48]

Answer:

1. What was the genetics of the man's father for aniridia? his genotype for the trait is Aa

2. Did the woman’s mother suffer from migraines? Yes, the women  inherited from her the dominant allele for migraines, M

3. What is the probability of this couple producing a child who is normal for both traits? 1/2 aamm

4. What is the probability of this couple producing a child who is afflicted by both traits? 0% of the progeny will be affected by both traits at the same time

5. What is the probability that a child of this couple will have normal vision and migraines? 1/2 aaMm

Explanation:

<u>Available data:</u>

  • Aniridia is due to a dominant allele, A.
  • Normal vision is due to the allele, a.
  • Migraine headaches are due to the dominant allele, M.
  • Normal headaches are due to the allele, m.

A man with normal vision and without migraines marries a woman with normal vision and migraines.

  • The genotype of the Man with normal vision and without migraines is  aamm
  • The genotype of the woman with normal vision and migraines is aaM-

The man's father had aniridia. This means that his genotype for the trait is Aa. We know that his son is homozygous for the recessive trait and that he must have inherited one recessive allele from the mother and the other recessive allele from his father. So, the man´s father must be heterozygous for the trait. If he was homozygous, the son would be heterozygous and would express aniridia.

The women's father had normal headaches but never a migraine. This means that his genotype is mm, recessive homozygous for the trait, which tells us that the women´s mother inherited her the dominant allele for migraines, and her father inherited her the recessive allele for the trait.

Cross:

Parental) aamm    x    aaMm

Gametes) am  am  am  am

                aM  aM  am  am

Punnet square)   aM       aM       am       am

                  am   aaMm  aaMm  aamm  aamm

                  am   aaMm  aaMm  aamm  aamm

                  am   aaMm  aaMm  aamm  aamm

                  am   aaMm  aaMm  aamm  aamm

F1) 8/16=1/2 of the progeny will have normal vision and migraines, aaMm

     8/16=1/2 of the progeny will have normal vision and will not have migraines, aamm

1. What was the genetics of the man's father for aniridia? his genotype for the trait is Aa

2. Did the woman’s mother suffer from migraines? Yes, the women  inherited from her the dominant allele for migraines, M

3. What is the probability of this couple producing a child who is normal for both traits? 1/2 aamm

4. What is the probability of this couple producing a child who is afflicted by both traits? 0% of the progeny will be affected by both traits at the same time

5. What is the probability that a child of this couple will have normal vision and migraines? 1/2 aaMm

8 0
3 years ago
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