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
lubasha [3.4K]
3 years ago
6

For natural selection to occur, variation must exist. this is true because without variation

Biology
1 answer:
chubhunter [2.5K]3 years ago
6 0
<span>Without variation, there is no difference between members of a population to be "selected for" in the first place. This is a basic tenet of natural selection. A new trait must arise in order to advance or decrease the fitness of the individual, and hence, its ability to pass on its genes.</span>
You might be interested in
PLEASE HELP ILL MARK BRAINIEST. Describe 5 specific jobs that proteins do in your body or in your cells, How is DNA different fr
Lana71 [14]

Answer:

1. Building Tissues and Muscles

Protein is necessary in building and repairing body tissues. If you do not receive enough protein in your diet, muscles wasting and other symptoms may result. Exercises like strength training cause micro tears in the muscle and as your body repairs these tears, it causes the muscles to enlarge. Protein is necessary to the immune response that helps to heal the tiny muscle tears. However, consuming extra protein will not help your body to build extra muscle.

2. Hormone Production

Hormones are chemicals produced by glands in one part of the body that help coordinate activities and communicate with other areas. Protein hormones bind to receptors on the cell membrane instead of entering the cell directly. Hormonal proteins, like insulin and oxytocin, play vital roles like controlling blood sugar concentration and stimulating contractions during childbirth. Hormones can also activate muscle growth by increasing protein synthesis or decreasing protein breakdown.

3. Enzymes

Enzymes are proteins that bind to molecules to speed up chemical reactions. They play a role in many activities such as muscle contraction and relaxation, and nerve impulse transmissions. Amylase and lipase are enzymes that help you to digest carbohydrates and fat. The enzyme ATPase exports cell toxins, and is essential for breaking down adenosine triphosphate, or ATP, which releases energy.

4. Immune Function

Antibodies are specialized protein configurations that provide a specific immune defense against invaders. They are produced by the body once it's exposed to specific antigens such as bacteria, viruses and fungi. Complement proteins support the immune system as a second line of defense. They can create holes in bacterial walls, promote inflammation which attacts macrophages that destroy invading organisms, and attach to the foreign substances.

5. Energy

Protein is broken down into amino acids during digestion and provides four calories per gram. Including protein with meals can help you feel more satiated, and can keep you fuller longer. Although protein can be used as an energy source, the body's main energy source is carbohydrates. Eating a diet with lean proteins like beans and fish, complex carbohydrates like whole grains and vegetables, and healthy fats such as olive oil and avocados is the best way to supply your body with energy.

There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.

A single DNA molecule is shaped as a double helix made up of two strands of nucleotides that are bonded together. Each nucleotide consists of a nitrogen base, a sugar (ribose), and a phosphate group.

Because there are only 20 different amino acids but 64 possible codons, most amino acids are indicated by more than one codon.

Explanation:

7 0
2 years ago
Why bacteria in the soil. are necessary in this ecosystem 8th Grade Science
liubo4ka [24]
There could be a lot of reasons. To help break down food for the plants, kill off bad and harmful things that might damage the plant. 
6 0
3 years ago
Read 2 more answers
What is a single population is made of?
Pepsi [2]
I think the correct answer from the choices listed above is option A. A single population is made of multiple organisms. In biology, population is a group of individuals which belongs to the same species that lives in the same area. Hope this answers the question.
5 0
3 years ago
Read 2 more answers
Rewrite this sentence: “As an organism develops, its cells take on different structures by expressing different combinations of
marusya05 [52]

Answer:

As organisms develop, it’s cells take on different forms by expressing different combinations of it’s genes.

Explanation:

6 0
3 years ago
Explain how and where volcanoes form (how the chemical composition of lava affects the type of volcano formed).
BigorU [14]

Answer:

Magmas differ in composition, which affects viscosity. Magma composition has a large effect on how a volcano erupts. Felsic lavas are more viscous and erupt explosively or do not erupt. Mafic lavas are less viscous and erupt effusively.

Explanation:

5 0
3 years ago
Other questions:
  • I can be found in animal cells is it chloroplast, mitochondria or both
    9·1 answer
  • WILL GIVE YOU BRAINIEST!!
    5·1 answer
  • A bacterium suddenly cannot manufacture proteins. What component[s] of the cell is [are] not working?
    5·1 answer
  • Hello i need help really badly. who can help me???
    13·2 answers
  • If four sizes of model cells are soaked in a ‘nutrient solution’, then the ______________ (smaller or larger?) cells will show t
    10·1 answer
  • How is a carrier shown in a pedigree?
    5·1 answer
  • Chromatids are attached to the...
    5·1 answer
  • 3 poi
    9·1 answer
  • Which of the following statements about complete metamorphosis is true? will give brainliest
    9·1 answer
  • Name one unique characteristic of the tobacco mosaic virus.
    14·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!