The Phenotypic Ratio 9:3:4 May Indicate

question 89

Multiple Choice

The phenotypic ratio 9:3:4 may indicate

• A) complete dominance.
• B) codominance.
• C) epistasis.
• D) recessive lethal.
• E) codominance and epistasis.

---

Definitions:

Axon

A long, slender projection of a nerve cell that typically conducts electrical impulses away from the neuron's cell body.

Myelin Sheath

A fatty layer that encases the axons of many neurons, crucial for increasing the speed at which electrical impulses propagate along the nerve cells.

Multiple Sclerosis

A chronic autoimmune disease where the immune system attacks the protective covering of nerves, affecting the brain and spinal cord.

Degeneration

The process of deterioration or decline in the quality, functioning, or condition of a living organism or its parts, often leading to loss of abilities or health.