Chemical Signaling by hormones(Chapter 3)

Question 1

what is the function of endocrine glands?

Answer 1

to secrete hormones’ which circulate in the bloodstream

Question 2

how does a target cell respond to a hormone?

Answer 2

they must have a hormone-specific receptors

Question 3

what four substances are used as both neurotransmitter in the brain and hormones endocrine system?

Answer 3

Norepinephrine
Epinephrine
Vasopressin
Oxytocin
NEVO

Question 4

what are the two adrenal glands? what respective hormones do they secrete?

Answer 4

adrenal medulla - secretes epinephrine (EPI) and norepinephrine (NE) (monoamines)

Adrenal cortex secretes glucocorticoids (steroid hormones)

Question 5

what are the two gonads glands? what respective hormones do they secrete?

Answer 5

Ovaries secrete estrogens and progesterone.

Testes secrete androgens (e.g., testosterone).

Question 6

where is the islets of Langerhans found in the body?

what respective hormones do they secrete?

what’s the purpose of the secretion of this hormone?

Answer 6

Islets of Langerhans in the pancreas – secrete insulin and glucagon(peptide hormones) – regulation of glucose

Question 7

what does the thyroid gland secrete?

what is the hormone responsible for?

Answer 7

secretes thyroxine (T4) and triiodothyronine (T3) –
regulate energy metabolism

Question 8

what does the pineal gland secrete?

what is the hormone responsible for?

Answer 8

secretes melatonin – control of sleep and other rhythms

Question 9

what does the pituitary gland secrete?

what is the hormone responsible for?

Answer 9

secretes hormones that control other glands

Question 10

what can underactivity of the thyroid gland do?

Answer 10

causes feelings of weakness and lethargy (even mimicking some of the symptoms of clinical depression)

Question 11

what does overactivity of thyroid gland do?

Answer 11

overactivity (hyperthyroidism) leads to excessive energy and nervousness

Question 12

what amino acid are the thyroid hormones made from? what other hormones are precursor of this amino acid?

Answer 12

These two thyroid hormones are made from the amino acid tyrosine

DA, NE, and EP

Question 13

what does the anterior pituitary secrete?

what is the hormone responsible for?

Answer 13

secretes stimulation hormones:
TSH=thyroid-stimulating hormone
GH=growth hormone
ACTH= adrenocorticotropic hormone
PRL=prolactin
FSH= follicle-stimulating hormone
LH= luteinizing hormon

Question 14

explain the function of the hypothalamus

Answer 14

secretes releasing hormones to trigger secretion of
stimulating hormones by the anterior pituitary.

Question 15

what faster, chemical communication by neurotransmitter or endocrine system? what the reason?

Answer 15

the endocrine system works more slowly than chemical communication by neurotransmitters. this is because of the multiple layers the endocrine system has to communicate

Question 16

what area of neurons release hypothalamic releasing hormones?

Answer 16

released by neurons in the median eminence

Question 17

what carries the hypothalamic releasing hormones?

Answer 17

Blood vessels carry them to the anterior pituitary.

Question 18

explain what hypothalamic releasing hormone stimulate what. list the three

Answer 18

Thyrotropin-releasing hormone (TRH) stimulates thyroid-stimulating hormone(TSH)

corticotrophin releasing hormone (CRH) stimulates adrenocorticotropic hormone (ACTH)

gonadotropin-releasing hormone (GnRH) stimulates follicle-stimulating hormone (FSH) and luteinizing hormone (LH)

Question 19

what gland does thyroid-stimulating hormone(TSH) effect?

Answer 19

Thyroid

Question 20

what gland does adrenocorticotropic hormone (ACTH) effect?

Answer 20

adrenal gland/cortex

Question 21

what gland does follicle-stimulating hormone (FSH) and luteinizing hormone (LH) effect?

Answer 21

ovaries’ and testis

Question 22

what gland does vasopressin effect?

Answer 22

kidney water retention

Question 23

where is Vasopressin (VP) and oxytocin (OT) synthesized?

Answer 23

in the hypothalamus by neurons whose axons reach the posterior pituitary gland (forming endings on blood vessels).

Question 24

what effect does oxytocin (OT) have?

Answer 24

stimulates uterine contractions during childbirth, and triggers milk letdown from the breasts

Question 25

what does alcohol do to vasopressin secretion? what’s the result of this effect?

Answer 25

Alcohol inhibits vasopressin secretion, which is one of the reasons why people urinate so frequently when they drink. because it helps with water retention

Question 26

what other effects might VP and OT have on the brain? why?

Answer 26

they effect the part of or interact with social behavioral neural network(recognition memory, bonding).

this is because neurons from the paraventricular nucleus connect to many other brain regions

Question 27

what does it mean to be sexually dimorphic pathways for VP and OT

Answer 27

influenced by gonadal steroids

Question 28

what are some oxytocin research?

Answer 28

OT can influence a variety of social behaviors, including empathy, altruism, trust, and social memory

Question 29

what does OT have the potential for?

Answer 29

OT may have potential in ameliorating the social deficits in autism spectrum disorder patients

Question 30

what is the mechanism of hormone action involved in peptide hormones?

Answer 30

Most peptide hormones act through membrane metabotropic receptors (receptor for VP and OT – stimulate phosphoinositide/activate PKC.

Question 31

what is the mechanism of hormone action involved in steroid hormones?

Answer 31

Steroid and thyroid hormones operate mostly through intracellular receptors in the cell nucleus; function as transcription factors (turn on/off gene expression)