Answer:
Option-D, a segment of DNA
Explanation:
A gene represents the particular segment of DNA which contains the instruction for the trait of an organism. The nucleotide sequence present in the segment provides the instruction in the form of codons.
The gene is present in the form of its alternative form called alleles which are located on the chromosomes at locus. The alleles represent the variants of the gene and therefore controls the two variety of a single trait.
Thus, Option-D is correct.
Answer:
maybe it helps
Explanation:
Daytime temperatures are often around 70°F (25°C) and occasionally 80°F (30°C) at lower elevations. Nights are usually cool and temperatures may drop below freezing at higher elevations.
Answer:
Option-D
Explanation:
Casparian strips are the strips or band composed of a hydrophobic substance called the suberin which forms the ring-like structure in the endodermis of the vascular plants.
The Casparian strips are present around the vascular bundles in the endodermis to allow the uptake of the selective nutrients as the substance has to pass through the cell membrane before it enters the centre of the root or stele or vascular bundles.
The Casparian strips allow the movement of a substance through symplast mode only, therefore, is ensures the substance to pass through the cell membrane.
Thus, Option-D is correct.