Bio 30 Endocrine system L1

Question 1

What is a chemical signal?

Answer 1

Any substance that affects cell metabolism or behavior of the individual.

Question 2

Where can chemical signals be used?

Answer 2

Can be used between body parts, between cells, and between individual organisms

Question 3

What is the endocrine system made of?

Answer 3

Consists of glands and tissues that secrete
hormones (chemical signals)

Question 4

Do endocrine glands have ducts?

Answer 4

Endocrine glands are ductless organs that
produce and secrete hormones directly into the bloodstream

Question 5

What are hormones and what do they do?

Answer 5

Chemicals that influence metabolism of cells, growth and development of body parts, and homeostasis

Question 6

What are four jobs hormones can do?

Answer 6

• Speed up the action of an organ
• Slow down the action of an organ
• Cause the release of other hormones (tropic)
• Alter the permeability of a cell to various
  nutrients i.e. insulin

Question 7

What causes hormones to be produced or released?

Answer 7

They can be produced or released in response to the nervous system OR to the other chemical in the blood (hormones).

Question 8

What is the difference in hormones response in the endocrine system vs. the nervous system?

Answer 8

Hormonal response is much slower than nervous response, but effect is much longer lasting.

Question 9

What regulates hormone production and secretion?

Answer 9

• Hormone production mostly regulated by
  negative feedback – once desired outcome reached, outcome inhibits further hormone release
• Hormone secretion usually controlled by
  negative feedback or antagonistic hormones – both result in homeostasis

Question 10

What are two classification of hormones?

Answer 10

• Tropic
• Non-tropic

Question 11

What are tropic hormones?

Answer 11

Tropic hormones have endocrine glands as their target causing the release of another hormone (e.g. Thyroid Stimulating Hormone (TSH) thyroid)

Question 12

What are non-tropic hormones?

Answer 12

Non-tropic hormones don’t have endocrine glands as their target rather affect target cells directly. (e.g. insulin - muscle, liver, fat cells)

Question 13

What does the hypothalamus do?

Answer 13

Regulates internal environment via autonomic system and controls secretions of pituitary gland (either by nerve stimulation from brain or release of hormones)

Question 14

What is the pituitary?

Answer 14

(“master gland”) has two portions: anterior and posterior

Question 15

What does the posterior pituitary do?

Answer 15

• Stores and releases antidiuretic hormone (ADH) and oxytocin produced by hypothalamus
• ADH secreted during dehydration causes
  more water reabsorption by kidneys; regulated by negative feedback
• Oxytocin, causes uterine contractions and milk release; controlled by positive feedback

Question 16

What does the anterior pituitary do?

Answer 16

• Hypothalamus controls anterior pituitary
  by producing hypothalamic-releasing hormones and hypothalamic-inhibiting
  hormones
• Anterior pituitary produces six hormones
  – four of these six hormones have an effect on other endocrine glands (i.e. tropic)

Question 17

What are 3 anterior pituitary: tropic hormones, and what do they do?

Answer 17

• Thyroid-stimulating hormone (TSH) stimulates the thyroid to produce thyroid hormones
• Adrenocorticotropic hormone (ACTH) stimulates the adrenal cortex to produce cortisol
• Gonadotropic hormones (FSH and LH) stimulate the gonads to produce sex cells and hormones.

Question 18

What are 2 anterior pituitary: non-tropic hormones and their functions?

Answer 18

• After childbirth, prolactin (PRL) causes
  mammary glands to produce milk
• Human growth hormone (hGH) promotes
  skeletal and muscular growth