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
Luba_88 [7]
2 years ago
12

A(n) is a protein and/or sugar molecule on the surface of a cell that allows the immune system to identify whether or not that c

ell poses a threat.
Biology
1 answer:
Lapatulllka [165]2 years ago
7 0

Answer:

Antigen

Explanation:

You might be interested in
Which of the following is not common to both prokaryotic and eukaryotic cell division?
julsineya [31]

The correct answer is: A checkpoint will be activated if the spindle does not attach to a kinetochore.

Prokaryotes, do not undergo mitosis (like eukaryotes) and therefore have no need for a mitotic spindle. Prokaryotes also don’ t have checkpoints foor the regulation of cell division.

Normal eukaryotic cells (unlike cancer cells), move through the cell cycle in a regulated way in order to make sure that cells don't divide under conditions that are unfavorable for them. Information about their own internal state (nutrients, signal molecules, DNA integrity) is signal to go or not to go through the cell division. Because of that there are few checkpoints in the cell cycle at which the cell examines the signals and makes a “decision”. The major checkpoints are:

• The G1- the first point at which it must choose, once it passes the G1 checkpoint the cell enters S phase

• The G2-the cell checks DNA integrity and checks if replication is done well.

• The spindle checkpoint-at the transition from metaphase to anaphase.

3 0
3 years ago
Read 2 more answers
What is the source of the energy that<br> flows through most of the food chains on<br> Earth?
Doss [256]

Answer:

the corret answer is the sun

Explanation:

The Sun is the major source of energy for organisms and the ecosystems of which they are a part. Producers such as plants, algae, and cyanobacteria use the energy from sunlight to make organic matter from carbon dioxide and water.

6 0
3 years ago
A malaria outbreak causing a Lily's frequencies to change is an example of
Dima020 [189]

Answer:

A malaria outbreak causing allele frequencies to change is an example of <u><em>natural selection.</em></u>

Explanation:

Natural selection is a type of selection in which those organisms are favoured to live and reproduce which are better adapted to live in an environment. Due to natural selection, the allele frequencies of a population will tend to change with the passage of time.

When the outbreak of malaria occurs, those organisms which do not catch malaria are able to survive and pass on their characteristics to their offsprings. the other organisms die and do not reproduce. This will cause changes in the allele frequencies.

6 0
3 years ago
Which evidence from the sea floor shows that tectonic plates move
blondinia [14]
<span> the sea floor is youngest near a mid </span>
<span>ridge and farther away. 

i think this is the answer</span>
8 0
3 years ago
which object is created during the formation of a star? a nebula a protostar a supergiant a supernova
Sever21 [200]

Answer:

nebula

Explanation:

3 0
3 years ago
Read 2 more answers
Other questions:
  • What cell would result from the endosymbiosis of a cell with a cyanobacterium ?
    5·1 answer
  • If the producers contained 40,000 kc al how much energy is remaining pyramid
    11·1 answer
  • What type of glands are the ceruminous glands?
    15·2 answers
  • In a breed of dogs, the BbEe genotype gives rise to yellow fur color, the Bbee genotype gives rise to black fur color, and bbee
    11·2 answers
  • The genetic code is redundant. What is meant by this statement?
    15·1 answer
  • The autonomic nervous system controls all of the following except the __________.
    15·1 answer
  • Please help <br><br><br> A<br> A<br> A<br> B<br> B<br> B
    6·1 answer
  • What is the target weight for a production owners hogs in the growing and finishing stage?
    14·1 answer
  • WILL MARK BRAINLEST. Punnett squares use mathematical probability to help predict the genotype and phenotype combinations in gen
    9·1 answer
  • What are genotypes of parent 1 and parent 2 Ss Yy
    7·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!