Which statement is true? The fissures are muscles that surround the lungs and facilitate breathing.
The bronchioles move oxygen into the bloodstream.
The pleural cavity keeps the lungs attached to the ribcage.
The lobules maximize the number of places where oxygen exchange can occur.

The amount of oxygen that is actually used by the body during the rest or a hand workout is determined by the heart rate, the stroke volume, and the amount of a. blood circulating in the vascular system b. oxygen removed from the vascular system c. oxygen provided to the vascular system d. blood that individual has in the body e. hemoglobin in the red blood cells

Which of the following describes the rooting reflex? a. a newborn turns the face toward a touch on the cheek in search of food. b. a newborn will automatically suck on objects placed in the mouth like a bottle. c. newborn immersed in water will display something like movement. d. newborn curls a hand around an object that touches the palm

Viruses use the host's machinery to make copies of themselves. however, some human viruses require a type of replication that humans do not normally have. for example, humans normally do not have the ability to convert rna into dna. how can these types of viruses infect humans, when human cells cannot perform a particular role that the virus requires? a) the virus causes mutations in the human cells, resulting in the formation of new enzymes that are capable of performing these roles.b) the viral genome codes for specialized enzymes not in the host.c) the virus infects only those cells and species that can perform all the replication roles necessary.d) viruses can stay in a quiescent state until the host cell evolves this ability.