The question is incomplete as it does not have the options-
A) Gamma-aminobutyric acid (GABA)
B) Acetylcholine
C) Dopamine
D) Serotonin
Answer:
The correct answer will be option- Dopamine
Explanation:
Parkinson's disease is one of the movement disorders which gets worse with time. The disease is caused due to the degeneration of the neurons in the brain which are responsible for the body movement.
Although many brain areas are affected the most common result is due to the loss of neurons in the substantia nigra in which the neurons produce a neurotransmitter called dopamine which is responsible for the body movements.
Thus, Dopamine is the correct answer.
The first statement above is an example of incomplete dominance. If
the calf has black and white spots then that’s an example of codominance.
Incomplete dominance is a form of transitional
inheritance in which one allele for an explicit trait is not entirely expressed
over its paired allele. This effects in a third phenotype in which the
expressed physical trait is a mixture of the phenotypes of both alleles.
Codominance<span> is a form of dominance by which the alleles of a gene
pair in a heterozygote are wholly expressed. This effects in offspring with a
phenotype that is neither dominant or recessive. A usual example showing this type of dominance is
the ABO blood group system.</span>
<span> </span>
Answer: Possession of Valves
Explanation: Veins possess valves which ensures that blood flows in only one direction. Valves helps blood to flow back to the heart against gravitational force.
Arteries don't have valves because the pressure originating from the heart is capable of causing the blood to flow in one direction.
The function of the digestive system<span> is </span>digestion<span> and absorption.</span>Digestion<span> is the breakdown of food into small molecules, which are then absorbed into the body. The </span>digestive system<span> is divided into two major parts: The </span>digestive tract<span> (alimentary canal) is a continuous tube with two openings: the mouth and the anus.</span>
Darwin noticed that there were different kinds of the same species. For example, he studied four different kinds of finches. Each one had a different beak and are different kinds of food. This was the first time genetic diversity had been so obvious to humans.