The answer to this question is salts, excess water, and sugars
An open circulatory system simply
means that the blood flows out of vessels and into the spaces or sinuses. Invertebrates,
insects and crustaceans has an open circulatory system where pump blood goes
into a hemocoel and diffusing back to the circulatory system between cells. In
other animals, the heart pumps the blood into the body cavities, spaces or
sinuses, where the blood surrounds the tissues.
To bring oxygen in the body because it is a respiratory organ fish
Acetylcholine (ACh)
Acetylcholine is an organic chemical that functions in the brain and body of many types of animals as a neurotransmitter.
Answer:
Topographically SN is classified into:
1. Central SN- made up of the brain and spinal cord
2. Peripheral SN- made up of nerves (31 pairs of spinal nerves, 12 pairs of cranial nerves), nerve plexuses and nerve ganglia
Structural Dpdv
1. Somatic SN \ of relationship life
2. Vegetative SN a) sympathetic- acts in unusual conditions (eg stress, fear)
b) parasympathetic- acts in normal life conditions
Explanation:
