I think the correct answer from the choices listed above is option B. The difference in biodiversity between the tundra and the tropical rain forest would be that warmer temperatures and higher average rainfall in the tropical rainforest allow more things to survive. Hope this answers the question.
Answer:
The statement that says " The mitochondrion contains a circular chromosome that has bacterial DNA sequences" is true among the all statement given above.
Explanation:
The Endosymbiotic theory that is other wise known as the symbiogensis illustrates the occurrence of the eukaryotic cell from the prokaryotic cells. Mitochondria and plastids are the most studied example in support of this theory. This theory explains that the aforementioned organelles are formed as they are taken inside in one another by the prokaryotic cell. Some of the evidences in support of this theory are mentioned below:
- Phylogenetic similarity between the mitochondria and chloroplast to the proteobacteria and cynobacteria respectively.
- Ability of these organelles to divide only through binary fission as the bacterial population.
- The associated ribosomes are similar to the bacterial ribosomes.
- Presence of porins in these organelles similar the bacterial membrane.
Answer:
4. B cells become activated by interacting with helper T cells.
1. B cells display antigens in MHC class II receptors on the cell surface.
2. Antibodies released by plasma cells bind to the antigen so they will be destroyed by other cells of the immune system.
3.B cells rearrange their DNA to create a unique B-cell receptor.
5. B cells undergo clonal expansion.
6. B cells digest antigens that bind to the antibodies on their surface.
Explanation:
B-cells get activated by interacting with helper T cells when they bind to the antigen to receptors i.e (MHC class II receptors on the cell surface) on the surface of the cell. Series of activities such as release by plasma cells which cause rearrangement of B cells causes the cell to divide and proliferate. The process through which daughter cells arise from a parent cell called clonal expansion.
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Answer:
The physicist himself
Explanation:
Replication in an experiment means to repeat an experiment as many times as possible using the same conditions. This is done to minimize error and ascertain the reliability of the experimental outcome.
An experimenter is responsible for repeating his/her experiments. According to this question, a physicist performs an experiment. The physicist himself should replicate his experiment.