Answer:
D. they are usually dominant or recessive.
Explanation:
alleles are pairs of genes found on a particular spot a chromosome. If one is dominant over the other it give rise to a particular trait.
A DNA molecule consists of two strands of nucleotides twisted together to form a double helix. The sugar-phosphate backbone is found on the outside of this helix and the bases are found braching towards the middle. Hydrogen bonds join the thenitrogenous bases and hold the two strands together.
Therefore your answer is sugar and phosphate.
Answer:
Chemicals that are secreted from antigen-presenting cells then activate helper T cells.
Explanation:
<span> D. energy storing
Photosynthesis uses energy from the sun to synthesize carbon-based molecules, that will serve as the energy for plants.</span>
Answer: Xylem is the specialised tissue of vascular plants that transports water and nutrients from the plant–soil interface to stems and leaves, and provides mechanical support and storage. The water‐conducting function of xylem is one of the major distinguishing features of vascular plants
Explanation: hoped this helped
