The eardrum is a thin flap of skin that is stretched tight like a drum and vibrates when sound hits it.
As the heart beats, it pumps blood through a system of blood vessels, called the circulatory system. The vessels are elastic, muscular tubes that carry blood to every part of the body.
Blood is essential. In addition to carrying oxygen from the lungs and nutrients to your body's tissues, it also takes the body's waste, including carbon dioxide, away from the tissues. This is necessary to sustain life and promote the health of all the body's tissues.
Answer:
Central posterolateral thalamus.
Explanation:
The third order neuron originates from Central posterolateral nuclei thalamus because it is the nucleus of thalamus because it receive impulses from the neospinothalamic tract and the medial lemniscus of the posterior column-medial lemniscus pathway i.e it received sensory information from the body, send it to the brain and then transfer the information to brodman.
Answer: Substances that are protein based cannot cross the lipid cell membrane, but can exert their effect by binding to the proteins based receptors present on the lipid bilayer.
Explanation:
Hormones such as calcitonin , Parathyroid hormone and pituatry horomones are proteins and water soluble.They cannot cross lipid bilayer but can bind to ligand binding protein receptors.
These receptors are protein macromolecules that are specific in nature for specific hormones.
After binding to the receptors, these hormone-recpetor complexes activate second messengers and regulate the downstream effects.
Microtubules are composed of two different types of tubulin. Namely, these simpler units are called alpha-tubulin and beta-tubulin. These subunits are essentially tightly bound together to form heterodimers. In the microtubule structure, they are arranged in an organized manner in such a way that they in parallel direction with protofilaments.