are chemical messengers secreted by glands. Exocrine glands, such as sweat glands, secrete fluids through ducts. glands secrete hormones directly into the bloodstream. The gland plays an important role in puberty and growth. Epinephrine, triggering the "fight or flight" response, is produced by the glands, which sit on top of the kidneys. Most glands that secrete hormones operate using feedback mechanisms. When hormone concentrations are high, the gland will produce of the hormone. Many cells produce chemicals called , hormone-like substances that impact inflammation and reproduction. The gland that helps regulate growth, body temperature, and the level of calcium in the blood is called the . Describe the function and compare steroidal and nonsteroidal hormones. How does each type of hormone interact with the cell? What other molecules are required for or involved in their function?

In tossing one coin 10 times, what are your chances for tossing a head? a tail? 2. in tossing one coin 100 times, what are your chances for tossing a head? a tail? 3. in tossing one coin 200 times, what are your chances for tossing a head? a tail? deviation = ((absolute value of the difference between expected heads and observed heads) + (absolute value of the difference between expected tails and observed tails)) divided by total number of tosses. this value should always be positive. 4. what is the deviation for 10 tosses? 5. what is the deviation for the 100 tosses? 6. what is the deviation for 200 tosses? 7. how does increasing the total number of coin tosses from 10 to 100 affect the deviation? 8. how does increasing the total number of tosses from 100 to 200 affect the deviation? 9. what two important probability principles were established in this exercise? 10. the percent of occurrence is the obtained results divided by the total tosses and multiplied by 100%. toss the coins 100 times and record your results. calculate the percent occurrence for each combination. percent head-head occurrence: percent tail-tail occurrence: percent head-tail occurrence:

What happens during interphase? (1)the nucleus grows to its full size. (2)the cell grows to its full size. (3)the nucleus divides into two nuclei. (4)the cell divides into two cells.

The first amino acid of a new polypeptide chain is