The blood cells that fight infection are the...
Leukocytes
The chamber of the heart that receives deoxygenated blood as it returns from the
body cells is the...
Right atrium
The shaft of long bones is the...
Diaphysis
The valve between the right atrium and right ventricle that prevents blood from
flowing back into the right atrium us the...
Tricuspid valve
The mucous membrane that lines the eyelids and covers the front of the eye is
the...
Conjunctiva
The basic structural unit of the nervous system is the...
Neuron
The blood vessels that contain valves to prevent blood from flowing in a
backward direction are the...
Veins
Which of the following is not a pair of salivary glands?
Submaxillary
The tube that connects the middle ear with the pharynx is the...
Eustachian
The sympathetic and parasympathetic nervous systems work together to
maintain a balanced state called...
Homeostasis
The material in bones that produces red blood cells, platelets, and some white
blood cells is the...
Red marrow
The gland in the male that contracts during ejaculation to aid in the expulsion of
semen into the urethra is the...
Prostate gland
The division of the autonomic system that acts in times of emergency is the...
Central
A circular structure behind the pupils that refracts light rays is the...
Lens
The first seven pairs of ribs are called...
True ribs
The organ behind the stomach that produces enzymes and hormone insulin is
the...
Pancreas
The muscle layer of the heart is the...
Myocardium