The Endocrine System Coloring Activities
Question Sheet -- KEY
Assignment: Read the overview on the Coloring Activity and color when instructed to do so. Then answer the questions below.
1. The endocrine glands are__ductless_glands that secrete _hormones_ directly into body fluids. The job of hormones is to help the body maintain _homeostasis_also known as biological balance with the internal and external environments.
2. Hormones regulate _chemical_reaction rates, water balance, the transport of substances through_membranes_and function in the processes of __growth_ & __development_.
3. Neurons of the_hypothalamus_are connected to the _pituitary gland_ by means of a narrow stalk or infundibulum. These neurons make and secrete hormones stored in the posterior pituitary gland. The _hypothalamus_ also releases hormones that stimulate the secretion of hormones in the anterior pituitary gland.
4. The pineal gland secretes_melatonin_. The activity of this hormone appears to be regulated by varying light conditions outside the body and has been implicated in circadian rhythms. Refer to p. 295 in your text and define a circadian rhythm. ___patterns of repeated activity associated with the environmental cycles of day and night, eg: sleep cycle__.
5. Located inferior to the larynx, anterior to and wrapping around the sides of the trachea is the_thyroid_ gland. This gland produces three hormones (p.286-87 in your text) _thyroxine__, __calcitonin_ & triiodothyronine. Triiodothyronine & _thyroxine_increase the rate of energy released from carbohydrates, increase the rate of protein synthesis, accelerate growth and stimulate the nervous system. _Calcitonin_
lowers calcium & phosphate ion concentrations in the blood by inhibiting their release from the bones and increases their excretion by the_kidneys_.
6. The 4_parathyroid_glands located on the posterior (dorsal) side of the thyroid gland produce the hormone_parathyroid hormone__or PTH (p.288 in text). It inhibits the activity of _osteoblasts_(bone builders) and stimulates osteoclasts to absorb bone calcium, increasing the_calcium_levels in the blood. This hormone also stimulates the absorption of calcium from food in the small__intestine_, increasing blood calcium.
7. The_thymus_gland sits behind the sternum. It produces hormones called _thymosins_ (See p. 365 in text) which stimulate the maturation of __lymphocytes_after they leave the thymus. The thymus__shrinks_as human’s age.
8. The_pancreas_ is largely a digestive organ producing a variety of digestive enzymes. It also produces two hormones__insulin_&__glucagon_. Glucagon stimulates the liver to breakdown_glycogen_and certain amino acids, producing _glucose_.
This results in_increased_ blood sugar levels. (see p.294 in text).
9. The second hormone released by the pancreas is _insulin_which stimulates the liver to make glycogen from glucose and inhibits the conversion of noncarbohydrates into _glucose_.
10. Insulin also promotes the facilitated _diffusion_ of glucose and amino acids into _cardiac_ & _skeletal_muscle as well as adipose tissue. It also _increases_ protein synthesis in cells and promotes the storage of__fat_in adipose tissue.
11. The__adrenal_glands sit atop the kidneys. They are divided into the adrenal _cortex_ & the _medulla_.(see p. 289 of text). The cells of the adrenal medulla produce __epinephrine_&_norepinephrine_. Both hormones increase _heart_ & _breathing_rates, increase the force of heart contractions, raise blood__glucose _levels and elevate __blood_pressure while decreasing _digestive_activity.
12. Cells of the adrenal__cortex_, which is superficial to the adrenal medulla, produces two steroid hormones. Aldosterone causes the kidney to conserve_sodium (Na+)_ions and excrete__potassium (K+) ions. This stimulates__water__retention, maintaining blood__volume_ & __pressure_. A second steroid hormone, __cortisol_, influences the metabolism of_glucose_, _protein_, & __fat_.
13. The kidney produces__erythropoietin_&__renin_, two hormones that regulate water balance in the body.
14. _Testosterone_is produced by the testes and regulates_sperm_production and secondary__male_characteristics.
15. Estrogens are produced in the_ovaries_. They support the _maturation_ & _growth_of the eggs and reproductive structures.