Answer:
In the first step of meiosis I, the chromosomes/genetic material of the cell condenses into a visible form, into a form called heterochromatin. The nucleolus also disappears.
In the second step, a process called synapsis occurs. This is when homologous chromosomes align themselves, gene by gene.
In the third step, crossing over occurs. Segments of corresponding DNA are cut and exchanged between non-sister chromatids of the formed tetrads.
In the fourth step, the nucleus fragments, the nuclear envelope fragments, the two centrosomes (if we're talking about an animal cell) separate from each other as their asters and mitotic spindles (mostly microtubules (kinetochore and non-kinetochore) lengthen. The microtubules extending from the centrosomes can now connect to chromosomes.
Answer: E) provide the defense for the CNS
Explanation:
Astrocytes can be defined as one of the cell types in the central nervous system. These are the dominant glial cell found in the brain. These cells perform a variety of functions in the brain. The functions includes axon guidance, synaptic support, controlling the blood brain barrier and blood flow. These cells maintain the chemical environment in the brain especially around the neuron.
These cells do not provide to the central nervous system.
It is because that's a place where no one lives so they're safe.
Answer:
The answer is B. the set of alleles.
Explanation:
Answer:
False
Explanation:
Sensory neurons send messages to the central nervous system.