Final answer:
Fat, water, and waste that accumulate under the skin are found in the hypodermis, which consists mainly of adipose tissue. The hypodermis serves as an energy reserve, provides insulation, and protects body structures. The distribution of fat is influenced by hormones, genetics, and differs by sex and age.
Step-by-step explanation:
The fat, water, and waste that collect under the skin is predominantly found in the hypodermis, also known as subcutaneous tissue. This layer primarily consists of adipose tissue which includes fat-storing cells called adipocytes. These adipocytes play a crucial role in energy storage, insulation, and protection of the deeper body structures from trauma.
The deposition and accumulation of fat in the hypodermis are influenced by hormones such as testosterone, estrogen, insulin, and others, along with genetic factors. The distribution of this body fat differs in males and females due to varying hormone levels and changes with age and puberty. In the evaluation of body fat content, the Body Mass Index (BMI) is frequently used, though it has limitations, especially in assessing the health of physically fit individuals.
It is important to note that the hypodermis is not part of the skin but lies beneath the dermis. Excess fat stored in the hypodermis can be associated with overweight and obesity, which are risk factors for various health conditions.