Answer:
The correct answer is D. The surface of the skin can be mapped into distinct regions, each served by a single spinal nerve: these regions are called dermatomes.
Explanation:
A dermatome is the area of skin innervated by a single spinal nerve and its spinal ganglion. The cutaneous nerves are those that reach the skin, picking up the sensitivity of the skin. Each cutaneous nerve is distributed in a certain area of skin, called a dermatome.
A pair of posterior or sensory roots and a pair of anterior or motor roots arise from each cord segment, joining laterally at the level of the intervertebral foramen to form a mixed spinal nerve. Each of these innervates a strip of skin called a dermatome, so the body surface can be considered a true mosaic of these.
In the extremities the arrangement of dermatomes is more complicated because of the embryological rotation of the limbs as they grow from the trunk.
Answer:
Mutagens can be described as substances which cause mutation. Mutations can be described as any changes in the DNA of an organism.
Mutations can be introduced by chemicals or naturally.
Mutagens which can cause mutations are:
- X-rays
- Ultraviolet radiation
- Chemical mutagens such as Alkylating agents such as ethylnitrosourea.
- Certain Alkaloid
- Bromine
Answer:
plantae
Explanation:
if the organism is multicellular, reproduces sexually, and is autotrophic, it belongs in the plantae kingdom, because those are all characteristics of plants.