Why can oxygen diffuse across a cell membrane but a protein cannot?
a) proteins are too large.
b) oxygen is polar.
c) oxygen is a gas.
d)proteins absorb oxygen

How would you describe an allele that be expressed and determines an organisms appearance? a.uncapitalized b.responsive c.recessive d.dominant

Explain the physiological changes that occur when the hypothalamus stimulates the sympathetic nervous system. you can make a flowchart or a simple step process. be sure to include all chemicals/hormones secreted, glands involved and the functions of each chemical/hormone.

Place the labels in order denoting the sequence of events of the cardiac cycle beginning with resting membrane potential and ending with the beginning of repolarization. the first and last steps are given.