Which of the following neurotransmitters typically has inhibitory effects?
a) gaba
b) glutamate
c) norepinephrine
d) substance p
e) none of the listed responses is correct.

The correct answer is: A) GABA

GABA or γ-aminobutyric acid is a type of amino acid that's found in proteins. It is the main inhibitory neurotransmitter in the brain which means that GABA reduces neuronal excitability throughout the nervous system. GABA binds to its receptors that are located on the neuron’s plasma membrane. This binding causes the opening of ion channels that transport chloride ions into the cell or potassium ions out of the cell.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.