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Iteru [2.4K]
3 years ago
6

Where does positive selection of t cells occur?

Biology
1 answer:
erik [133]3 years ago
3 0
Positive selection of t cells occur in .the thymus
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How do fungi benefit from being able to reproduce both asexually and sexually?
Alekssandra [29.7K]
Asexual reproduction is an advantage because they don't need to depend on contacting a suitable mate, or expand energy producing gametes and attractions, in order to spread .

sexual reproduction is an advantage because it enables the exchange of genetic information and produces variety in the offspring that makes them more resilient and capable of adapting to changes in their environment .
4 0
3 years ago
Which statement about an ecosystem is incorrect?
kumpel [21]
There is a community of organisms but no no living components
6 0
3 years ago
The degradation of the environment from litter is a A. a negative externality. B. free rider problem. C. Tragedy of the Commons.
AlekseyPX

Answer:

D. Both a and c are correct.

Explanation:

The tragedy of the commons is a situation in a shared-resource system where individual users, acting independently according to their own self-interest, behave contrary to the common good of all users by depleting or spoiling the shared resource through their collective action.

It damages our environment (plants, animals) and impacts local tourism. It is smelly and dirty, and carries germs, bacteria and viruses. Places with a high degree of littering see a decreases in property values, and are more likely to be the site of fires.

Pollution is a negative externality. Economists illustrate the social costs of production with a demand and supply diagram. The social costs include the private costs of production incurred by the company and the external costs of pollution that are passed on to society.

Blowing litter can cause automobile accidents as well as land and air pollutions

7 0
3 years ago
Compare and contrast the five layers that make up the atmosphere.
Wittaler [7]
Exosphere is in the top 600-800km exosphere has a very low amount of gases almost like in outer space.

Termosphere, 80-600km absorbs gamma rays uv rays and rays that damage our healt also know as ionosphere, is the hottest one.

Mesosphere, 50-80km, the temperature here reaches -140 Celsius shooting stars are formed here

Stratosphere, 12-50km produces the mayor part of the atmospheric ozone, some army planes reach this later

Troposphere, thats the source of the mayor part of the gases here in the atmosphere.

Please please if I was useful please mark this as brainlyest
5 0
3 years ago
Read 2 more answers
Someone help me please
frez [133]
1. Two genetically identical copies of DNA

2. Finds an error in DNA, removes the incorrect nucleotide and replaces it with a correct one.

3. It is used as a copy/ "template" for replication in order to have two identical copies of DNA.

4. DNA helicase unwinds DNA double helix and Topiosomerase ensure there isn't too much unwinding.

5. Replication has a built on proofreading system - DNA polymerase removes the incorrect nucleotide and replaces it with a correct one.
5 0
3 years ago
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