ENDOCRINE SYSTEM Session 8

Question 1

What do the endocrine and exocrine glands both do ?

Answer 1

• Exocrine glands : Secrete their products into ducts
• Endocrine glands : secrete their products into the bloodstream , which delivers them throughout the body

Question 2

What type of cell is the only one that can respond to a hormone ?

Answer 2

• Target cells , they have receptor proteins for that hormone

Question 3

What are some example of peptide hormones ?

Answer 3

• Peptides , proteins , glycoprotein and modified amino acids

Question 4

What are steroid hormones derived from and what structure do they have ?

Answer 4

• Derived from cholesterol , and all have sample complex of four carbon rings

Question 5

What is an enzyme cascade and what is the first step in it ?

Answer 5

• The first step is that cyclin adenosine monophosphate ( cAMP ) is formed.
• Enzyme cascade is when activation of one enzyme leads to another enzyme being activated and its carried on.

Question 6

How do peptide hormones interact with target cells ?

Answer 6

• Peptide Hormones usually does not enter target cells , there fore there is another hormone called the first messenger which activates another hormone called second messenger to carry on .

Question 7

Which 3 places are the only locations in the body that produces steroid hormones ?

Answer 7

• Adrenal Cortex
• Ovaries
• Testes

Question 8

What do the steroid hormones bind to ?

Answer 8

• They do not bind to plasma membrane receptors and since they are hydrophobic , they are able to cross the plasma membrane and it binds to a receptor in the nucleus or cytoplasm

Question 9

What does the steroid hormone do inside the nucleus once binded to a receptor ?

Answer 9

• It then binds with DNA and activates certain genes and mRNA moves to the ribosomes and protein synthesis follows

Question 10

What does the hypothalamus do ?

Answer 10

• it links the nervous and endocrine systems together
• Regulates the internal environment via the autonomic nervous system

Question 11

What helps to connect the pituitary gland to the hypothalamus

Answer 11

• A stalk ( infundibulum )

Question 12

What do the neurosecretory cells in the hypothalamus produce and where are they stored after ?

Answer 12

• Antidiuretic Hormone (ADH)
• Oxytocin
• they are then stored in the posterior pituitary

Question 13

What happens when blood is too concentrated ?

Answer 13

• ADH is released form the posterior pituitary and it causes more water to be reabsorbed Into kidney capillaries and then when blood becomes dilute , ADH is no longer released

Question 14

What is diabetes insidious and what does cause ?

Answer 14

• It is the inability to produce ADH
• It also produces large amounts of urine , resulting in severe dehydration and loss of important ions

Question 15

What does oxytocin do ?

Answer 15

• Causes uterine contractions during childbirth and milk letdown during breastfeeding

Question 16

What are some ways that causes the release of oxytocin ?

Answer 16

• The more the uterus contracts , the more nerve signals reach the hypothalamus and causes oxytocin release
• As a baby suckles while being breastfed , nerve signals from the breasts reach hypothalamus and oxytocin is released

Question 17

How is the release of oxytocin controlled
?

Answer 17

• Positive feed back

Question 18

How does the hypothalamus control the anterior pituitary ?

Answer 18

• by producing hypothalamic releasing and hypothalamic inhibiting hormones