Which structure regulates the amount of light entering the eyeball through the pupil?

a) Retina
b) Cornea
c) Iris
d) Choroid
e) Ciliary muscle


Iris

Anatomy & Physiology

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What is the largest type of neuromodulator?

a. ATP b. nitric oxide c. serotonin d. dopamine e. neuropeptides

Anatomy & Physiology

Pain that feels like it is coming from a part other than the part being stimulated is called ________ pain.

Fill in the blank(s) with the appropriate word(s).

Anatomy & Physiology

Which stage of the cell cycle immediately precedes the S phase?

A. G2 B. G1 C. M D. None of the choices are correct.

Anatomy & Physiology

The plasma membrane of an excitable cell is more permeable to potassium ions because

A. of its positive electrical charge. B. there are more leak ion channels for K+ than Na+. C. protein molecules cannot exit through the cell membrane. D. calcium ions block Na+ and Cl- channels. E. there are more gated channels for K+.

Anatomy & Physiology