The answer for this question would be Integument, digestive, respiratory and urogenital.
The largest system that contact with the external environment would be integument and digestive. That makes two system has normal flora of microbes and not sterile like the other systems. Normal flora of microbes will prevent the pathogen microbe grows so it gives some benefit.
Answer: c. It is the first hominin known to have migrated out of Africa.
Explanation:
The Homo erectus were the ancient humans which are considered to be over first relatives which used to have human like body shape, short arms and long legs relative to their torso. The main unique feature about these humans is that these were the first humans which migrate out of the Africa and they were the first humans who starting cooking of food for the first time.
Answer:
Explanation:
The proteins in enzymes are usually globular. The intra and intermolecular bonds that hold proteins in their secondary and tertiary structures are disrupted by changes in temperature and pH. This affects shapes and so the catalytic activity of an enzyme is pH and temperature sensitive.
Answer:
Demography is the statistical study of human populations. Demography examines the size, structure, and movements of populations over space and time. It uses methods from history, economics, anthropology, sociology, and other fields.