1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tom [10]
3 years ago
11

DDT is an insecticide that was used extensively in the mid-1900s to kill mosquitoes. It was very effective at first, but after a

few decades DDT became less effective at killing mosquitoes because many populations had evolved resistance to DDT. Which of the following conditions would biologists say was required for the evolution of DDT resistance in a population?
a. A few mosquitoes in the population were resistant to DDT before it was ever used.
b. Mosquitoes in the population learned to adapt to the high levels of DDT in the environment.
c. The mosquito population needed to evolve DDT resistance in order to avoid extinction.
d. Exposure to DDT caused specific, nonrandom mutations for DDT resistance within the population.
Biology
1 answer:
dlinn [17]3 years ago
8 0

Insect populations can develop resistance to insecticides over time. The evolution of resistance is associated with an increase in the frequency of adaptive genes in the population.

  • In the case above described it is expected that a few mosquitoes in the population were resistant to DDT before it was ever used (Option a is correct).

  • Dichlorodiphenyltrichloroethane (DDT) is a pesticide used in agriculture.

  • After exposure to DDT, those individuals in the mosquito population that didn't carry gene variants (i.e., alleles) associated with the resistance to this pesticide died.

  • Subsequently, insects having adaptive alleles associated with DDT resistance survived and reproduced, thereby increasing the frequency of adaptive genes/alleles in the population.

Learn more in:

brainly.com/question/6389591?referrer=searchResults

You might be interested in
What is the significance of a chemical formula?​
Allushta [10]

Answer:

<em>The </em><em>significance</em><em> of</em><em> </em><em>chemical</em><em> </em><em>formula</em><em> is</em><em> </em><em>that </em><em>it </em><em>tells </em><em>us </em><em>a </em><em>lot </em><em>about </em><em>the </em><em>chemical</em><em> </em><em>reaction</em>

<em>like </em><em>the </em><em>name </em><em>of </em><em>elements</em><em> </em><em>involved</em><em> in</em><em> it</em><em>,</em><em> </em><em>number</em><em> of</em><em> </em><em>atom </em><em>of </em><em>each </em><em>element</em><em> </em><em>and </em><em>it </em><em>also </em><em>shows</em><em> </em><em>that</em><em> </em><em>which </em><em>type</em><em> of</em><em> </em><em>reaction</em><em> is</em><em> </em><em>going</em><em> on</em>

<em>like </em><em>exothermic</em><em> </em><em>and </em><em>endothermic</em><em>,</em><em> </em><em>combination</em><em>,</em><em> decomposition</em><em> </em><em>etc </em>

<em>hope</em><em> it</em><em> helps</em>

4 0
3 years ago
The process of cellular respiration can be represented by the chemical formula
Mandarinka [93]

Answer:

A

Explanation:

The correct formula for cellular respiration is: 

Glucose (sugar) + Oxygen → Carbon dioxide + Water + Energy (as ATP).

7 0
3 years ago
Alex is at a rock concert. when his ears send a signal to his brain that he has heard a sound, this process is most accurately c
I am Lyosha [343]
Alex is at rock concert. ..................................................... is most accurately called SENSATION. But ................................................. is most accurately called PERCEPTION.
Sensation occurs when light waves enter the sense organs and get converted to electrical impulses. The sense organs involve in this case are the senses of touch, sight, smell, hearing and taste. Perception occurs when the brain send signals to the body which result in identification or recognition of the sensation.
3 0
3 years ago
A medical test indicates that a patient has a defective protein. This
OleMash [197]

Answer:

number of nitrogen bases

Explanation:

<em>The correct answer would be the number of nitrogen bases.</em>

<u>A defective protein is usually caused by mutation, which is defined a change in the DNA sequence of an organism.</u>

Mutation can occur in a variety of ways including:

<em>1. Deletion of nucleotide base sequence in the DNA</em>

<em>2. Addition (insertion) of nucleotide base sequence in the DNA</em>

<em>3. Duplication of nucleotide sequence in the DNA</em>

<u>A change in number of phosphate molecules, sequence of subunits DNA and sequence of sugar molecules if possible in nature, do not lead to mutation if the change does not affect the sequence of DNA.</u>

Hence, the correct option is number of nitrogen bases.

6 0
3 years ago
Which plane separates your chest from your spine?<br> inverse
erma4kov [3.2K]

Answer:

Coronal Plane

Explanation:

It is also known as Y-X plane or Frontal planes; the coronal plane divides the body into ventral (front) and dorsal (back) portions.

5 0
3 years ago
Read 2 more answers
Other questions:
  • A scientific law
    8·1 answer
  • Discuss what to do if your are concerned about your child's development​
    8·1 answer
  • What are these species a type of?
    9·1 answer
  • Krypton is named after the Greek word that means “secret.” Which explains why krypton was most likely given this name? Krypton i
    15·2 answers
  • Help now! For biology
    12·1 answer
  • One example of how applied science has had a direct effect on daily life is the presence of vaccines. Vaccines to prevent diseas
    14·1 answer
  • What effects would you expect uncontrolled celiac disease to have on children? How do these effects relate to what is shown in t
    5·2 answers
  • Describe the role of the double fertilisation in angiosperm reproduction
    7·1 answer
  • 1) What surface characteristics affect the rate of heating and cooling?
    13·1 answer
  • What effect does reusing or recycling municipal have on environmental resources?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!