Estrogens from the vesicular follicle trigger an LH surge from the anterior pituitary. This is an example of: Estrogens from the vesicular follicle trigger an LH surge from the anterior pituitary. This is an example of: negative feedback first tier of control positive feedback fourth tier of control

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

the tricuspid valve is present between right atrium and right ventricle

well first you need the sample of the temperature and gas level. i couldnt write a hypothesis unless i had some data. i think temperature changes will effect volumes of gas because gas changed into a solid or liquid at specific temperatures.