Answer:
By the end of prophase, each of the following has occurred except <em>lining up of chromosomes in the cell.</em>
Explanation:
The lining up of the chromosomes in the cell occurs during the third stage of cell division. This stage is termed as the metaphase.
Prophase is the first stage of cell division. Hence, the lining of the chromosomes does not occur by the end of prophase.
During the prophase, the chromatin material condenses and become more compact so that the chromosomes become visible. The nucleolus and the nuclear envelope disappear by the end of prophase. Hence, all other options A, B and C occur by the end of prophase except option D.
I would say (A) because it allows the bacteria (bacteria X) to be exposed to the control condition and the experimental condition so that a cause-effect relationship can be established. Here, the control condition would be the darkened area and the experimental condition would be the lightened area.
Answer:
Bronchospasm
Explanation:
Bronchospasm is known to be a condition that results from the contraction of the muscles that is found in the wall of the bronchioles which result into obstruction and narrowing of the respiratory airway. Thus, substance released from basophils or mast cell under the control of anaphylatoxin usually causes Bronchospasm. Furthermore, Bronchospasm is commonly caused by asthma and can also be caused by allergic reactions, respiratory infection, and chronic lung diseases.
Answer: option A, B and D
Explanation:
The telomeres found at the terminal ends of eukaryotic chromosomes are long repetitive sequences that protects the DNA from being identify as a damage molecule to encourage fusion with other chromosomes. Since replication does not extend down to these 3' ends, the cell recruits the telomerase enzyme which is a ribonucleoprotein that helps to add telomeric repeats using its own RNA component as template to extend this end. Thus if mutation like a large deletion occurs in the gene encoding for this enzyme, the telomerase would not be able to associate correctly with the telomere, the catalytic center also encoding for its RNA polymerase would be altered and the enzymes will not be able to synthesize new telomeric repeats sequences