Answer:
True
Explanation:
Mitosis results in two cells that are genetically identical. DNA replication only occurs during "S phase." Meiosis is commonly defined as a type of cell division that divides a somatic cell and produces four gamete cells when doing so.
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<u><em>S phase:</em></u> In S phase, the cell synthesizes a complete copy of the DNA in its nucleus. It also duplicates a microtubule-organizing structure called the centrosome. The centrosomes help separate DNA during M phase.
<u><em>Gametes</em></u> are an organism's reproductive cells. They are also referred to as sex cells. Female gametes are called ova or egg cells, and male gametes are called sperm. Gametes are haploid cells, and each cell carries only one copy of each chromosome.
There are chances of 75% solid green coloured rind in watermelons.
Explanation:
Dominant trait = Solid Green rind G
Recessive trait= stripes g
Given that both the parent plants are heterozygous so their alleles will be
Gg Gg
From the Punnet square
G g
G GG Gg
g Gg gg
The phenotype ratio is 3:1 ( 3 watermelons with the green colour rind and 1 with striped rind observed)
Genotype ratio is 1:2:1
From the observation, we can say that 75% of the watermelons will have solid green colour rind because G is dominant over g.
The correct answer is B: The cells will have 2n chromosomes and be diploid.
Diploid cell have two of each chromosome, one from each parent. When diploid cell undergoes mitosis, the result is two identical diploid cells (when haploid cell undergoes mitosis the result is haploid cell). This means that during the mitosis, cells reproduce genetically identical copies of themselves.
Any cells of the human body, except the cells of a placenta.
Answer: The diffusion of ions along the axoplasm is faster,in myelinated compare to unmyelinated,
Neurons are the structural and functioning units of nervous system.They are the vehicles for transmission of impulses as electrical signals from one part of the cells,and from one part of the body to another.
The basic structural components of a typical neuron are the cellbody, the axon, and the dendrites.
Based on structure neurons are classified as myelinated and unmyelinated.This is based on the the surrounding layer of myelin sheath around the axon. The myelin provides the insulating layer for the axon.And ensures fast movement of impluses.
In myelinated neurons the myelin sheath are interrupted at intervals by gaps along the length of the axon called Nodes of Ranvier. These gaps contains more Na-K channels for influx and out-flux of K and Na+ ions for transmission of impulses.
The cytoplasm of axon is called axoplasm,Since this is surrounded by myelin sheath which contains Na-K+ channels,The rate of diffusion of ions along these channels is faster for depolarization to take place than in unmyelinated neurons. Inaddtion as these ions diffusion increases,its jump faster at the nodes of Ranvier (saltatory conduction) to the next axoplasm which further speed up the rate of transmission.
Unmyeinated lacks myelin sheath,therefore the exchange and the rate of diffusion of ions along the axons is low.
Explnation:
