The model shown in the diagram describes how the tongue works. When a red block is placed into a the correctly shaped hole, the nearest bulb lights up. A lit bulb represents a signal being sent to the brain. According to the model, how does the tongue function?

A) The tongue alerts the brain when food is absent.
B) The tongue changes the shapes of food molecules.
C) The tongue contains special cells for different types of food molecules.
D) The tongue receives information from the brain to determine how food tastes.

Which level of organization is the HIGHEST?
1 point
A) tissue
B) an organ
C) an organism
D) an organ system

Which represents the correct order of cell organization after cellular differentiation (simple to complex)?
1 point
A) organ system→organ→tissue→cell
B) cell→organ→organ system→tissue
C) tissue→cell→organ→organ system
D) cell→tissue→organ→organ system

Cells undergo differentiation during embyonic development. An individual skin cell develops differently from a muscle cell because
1 point
A) the cells have different DNA.
B) the cells have different genes.
C) the cells express different genes.
D) the cells have different chromosomes.