11. in a long bone, such as the femur in the leg, the center of the bone contains which substance, responsible for producing blood
cells?
o a. plasma
b. ligaments
c. marrow
o d. synovial fluid

The nervous system interacts with the endocrine system by a. using hormones as connections b. sending nerve impulses directly to glands c. using neuroendocrine cells as connections d. sending neurotransmitters directly to neurons

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes

Genetic orders can result when sister chromatids fail to separate properly during which phase is this problem most likely to occur