Why are muscle and fat levels the only factors influencing flexibility impacted by personal decisions?
a. muscle and fat levels are mostly determined by heredity.
b. age, gender, and joint structure cannot be changed.
c. personal decisions have significant impacts on age and gender.
d. flexibility is not dependent upon muscle and fat levels.

Jim and phil are changing the oil in jim’s car. jim is trying to remember all the actions involved in changing the oil. phil is trying to remember the first time he ever changed the oil in his car. jim is trying to recall a memory and phil is trying to recall a(n) memory.

What is the main structural difference between enveloped and nonenveloped viruses? a) enveloped viruses have their genetic material enclosed by a layer made only of protein.b) nonenveloped viruses have only a phospholipid membrane, while enveloped viruses have two membranes, the other one being a protein capsid.c) enveloped viruses have a phospholipid membrane outside their capsid, whereas nonenveloped viruses do not have a phospholipid membrane.d) both types of viruses have a capsid and phospholipid membrane; but in the nonenveloped virus the genetic material is between these two membranes, while in the enveloped virus the genetic material is inside both membranes.

Me d: which system contains the heart, blood, and blood vessels? a. muscular b. circulatory c. respiratory d. digestive which system contains the pituitary, adrenal, and thyroid glands? a. respiratory b. circulatory c. endocrine d. reproductive