Which of the following statements regarding skeletal muscle is true?
A. Individual skeletal muscle cells are visible to the naked eye.
B. Skeletal muscle is attached to bones by tendons.
C. Skeletal muscle cells do not contain nuclei.
D. Skeletal muscle is largely responsible for involuntary body motions.
E. Skeletal muscle coordinates movement of nutrients and oxygen throughout the body.
Which of the following statements about artificial skin is FALSE?
A. Artificial skin has been used on burn victims.
B. Artificial skin is grown from human fibroblasts.
C. Artificial skin is inexpensive and easy to use.
D. Artificial skin has shown such success that other artificial tissues are under investigation.
E. Artificial skin may not be used on any animal, just humans.
The nervous system and endocrine system control the body's functions by ___.
A. maintaining a constant level of nerve impulses
B. sending out messages by nerve impulse and hormones
C. responding only to the internal environment
D. stimulating the body's reproductive organs
Which of the following imaging techniques is best suited for visualizing fine anatomic detail in the brain?
A. electrocardiogram
B. X-ray imaging
C. magnetic resonance imaging (MRI)
D. positron-emission tomography (PET)
E. X-ray tomography
Which of the following imaging techniques is used for visualizing areas of high or low metabolic activity?
A. computerized tomography (CT)
B. X-ray imaging
C. magnetic resonance imaging (MRI)
D. positron-emission tomography (PET)
E. X-ray tomography
Assume you have scratched a mosquito bite and, in the process, damaged some of your stratified squamous epithelial cells. What will happen?
A. The damaged cells will heal themselves.
B. The cells near the base of the epithelium will rapidly replicate to replace the damaged cells.
C. Sensory receptors in the skin will become activated.
D. Vitamin D synthesis will begin, thus encouraging cell replacement.
E. The function of the skin will be totally lost.
Imagine an invertebrate that lives in an estuary where salinity varies cyclically with the tides. If this individual is able to adjust the salt concentration of its body fluids, its salt concentration will have
A. adjustments within the cell to equal salt concentration outside the cell.
B. slight fluctuations that are kept within a narrow range.
C. regular variatons that range from large to small.
D. a cyclic variation similar to that of the surrounding water.
E. a cyclic variation depending upon when the animal drinks.
If your body is dehydrated, having insufficient fluid levels in the blood, the control center in the brain will stimulate the release of a hormone which will cause water to be reabsorbed into the blood during urine formation. When the control center senses that enough water is reabsorbed, it will stop the release of the hormone. This is an example of ___.
A. a negative feedback mechanism
B. a positive feedback mechamism
C. response too external stimuli
D. lack of control over homeostasis