A scientist noticed that the number of salamanders in ponds in the Rocky Mountains was declining. This was a (n)

a. hypothesis.

c. observation.

b. theory.

d. control.

2. Oxygen is delivered from the lungs directly to your blood stream

The white blood cells that fight bacterial infections and attack cancer cells and viruses are called Group of answer choices lymphocytes. carcinogens. glucocorticoids. telomeres. neurotransmitters.

The electric signal for a contraction passes rapidly from one heart muscle cell to the next by way of

Larry is a 39-year-old male who is overweight. he is working with a registered dietitian nutritionist and she has recommended an 1,800-kcal diet for gradual weight loss.

The rest of plays movement can be seen at

Joshua cut his knee while rock climbing. The next day, the cut was red and swollen, and pus was present in the area of the cut. What caused the pus to form? A. macrophages excreting medicinal material B. the death of macrophages C.

Match the description in column 1 to the corresponding parts of the nervous system in column 2. A. Brings messages to your brain through your spinal cord autonomic B. If you stub your toe, this carries the message peripheral C.

when listening the levels of orginization in orginisims from the smallest to most complex, which level is just below organs in complexity

Relative to rainfall, the tundra is most like what other biome

Which artery is felt when taking the pulse at the wrist?