The right option is; C. They are controlled by more than one gene
Traits such as skin color, human height and eye colour are known as polygenic traits. These traits have wide variation throughout the human population and are controlled by two or more genes. For example the human height is controlled by at least three genes with six alleles. The quantities of the genes are usually large but often have a little effect.
Cone Cell: Adapted to form color images. concentrated in the retina
<span>Construct a hypothesis.</span>
Answer A:
1. Spiral chloroplast:
This organelle help in photosynthesis, because it contain green pigment called chlorophyll in which water and carbon dioxide combine in the presences of sun light to prepare glucose.
2. Cell wall:
It is chemically composed of<span> an outer layer of pectin and an inner layer of cellulose. It provide rigidity and shape to spirogyra cell.</span>
Answer B:
The other parts which are not labelled include mucilage, cytoplasm, pyrenoids, cytoplasmic strand.
Answer C:
Function of pyrenoid:
<span>Each chloroplast strand has several round bodies called 'pyrenoids', which are responsible for starch production.
</span>Function of mucilage:
Mucilage help in retaining water in cell.