Why is lactose intolerance so common?

What will be an ideal response?


Answer: Historically, in most parts of the world, milk as not available as a food for adults (only for nursing infants). Therefore, in most parts of the world, humans evolved to not express the lactase gene after approximately the age of two.

Anatomy & Physiology

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When a neurotransmitter causes the opening of chemically gated potassium channels on the postsynaptic cell, the postsynaptic potential that results is an

A.  EPSP, which is a depolarization.
B.  EPSP, which is a hyperpolarization
C.  IPSP, which is a depolarization.
D.  IPSP, which is a hyperpolarization.

Anatomy & Physiology

The sensation of taste is carried on axons of the following cranial nerve(s): ________

A) V B) VII, IX, and X C) I D) III, IV, and VI

Anatomy & Physiology

A __________ is a procedure where a temporary opening is made in the trachea to allow airflow when the upper airway is obstructed.

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

Anatomy & Physiology

Placing pure water around cells causes the cells to swell because the cytosol has a lower osmotic pressure than the pure water

Indicate whether the statement is true or false

Anatomy & Physiology