Final answer:
In hairstyling, the amount of closeness or fullness is affected by 'stem placement', which is related to the angle of hair wrapping. The hair matrix contains a layer of basal cells responsible for hair growth.
Step-by-step explanation:
The base control used within a hairstyle affects the amount of closeness in the hairstyle or the amount of fullness, which is also called stem placement. This term refers to where the base of the curl is positioned in relation to the scalp. Closeness or fullness in a hairstyle is controlled by the angle at which the hair is held while wrapping it on a roller or forming the curl. Holding the hair at 45 degrees or more away from the head creates more volume and fullness (off-base placement), while holding it closer to the head creates a tighter, more close-fitting style (on-base placement).
Regarding the hair matrix, the correct option is that it contains a layer of basal cells. The hair matrix is a cell-rich structure found at the base of the hair follicle. This part of the follicle is where cell division occurs, leading to hair growth.