Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Cells to systems > lecture 24 > Flashcards

lecture 24 Flashcards

1
Q

What are peptides

A

chains of specific amino acids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are amines

A

Tyrosine derivatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are steroids

A

Cholesterol derivatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are Eicosanoids

A

Arachidonic acid derivatives. Usually
act as autocrine or paracrine signalling molecules, but
can act distally

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What hormones are • Insulin, vasopressin, TSH, calcitonin etc

A

Peptides

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What hormone are • a) Catecholamines (Adrenal Medulla)
• Adrenalin & noradrenalin
• b) Thyroid hormones
• Thyroxine & triiodothyronine

A

Amines: Tyrosine derivatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What hormones are • Cortisol, aldosterone, oestrogen,

testosterone etc

A

Steroids:

• Adrenal cortex, gonads & placental hormones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 4 families of eicosanoids

A

—the
prostaglandins, prostacyclins, the thromboxanes
and the leukotrienes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What solubility of peptide hormone

A

Hydrophilic (polar)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What syntheses peptide hormones

A

Rough ER,

Packaged in Golgi complex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where are peptides stored

A

Secretory granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How to secrete peptide hormone

A

exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How are peptide hormones transported

A

Free hormone: soluble

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are the receptors of the peptide hormones

A

Surface of target cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What action can peptide hormone cause

A

Ion channel changes or

Second messenger system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What produces insulin

A

Anabolic hormone produced in the pancreatic b

cells in times of excess nutrient availability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the main role for insulin

A

Allows the body to use carbohydrates as energy

sources and store nutrients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does insulin target

A

Liver, muscle, adipose tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the functions of insulin

A

• Lowers blood glucose levels
• Increases facilitated diffusion of glucose into cells
• Increases conversion of glucose into glycogen
(glycogenesis)
• Increases uptake of amino acids and protein
synthesis
• Increases synthesis of fatty acids (lipogenesis)
• Slows glycogenolysis
• Slows gluconeogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some insulin receptor

A

Example of enzyme-linked receptor (tyrosine kinase)

• Tyrosine phosphorylation triggers multiple pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the most important regulator of insulin secretion

A

glucose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are all the factors controlling insulin secretion

A 
• -b cells monitor levels of circulating
metabolites
• Glucose
• Leucine & alanine
• Amino acids have little effect in
absence of glucose increase, but they
double insulin release in combination
with glucose
• Neuronal & hormonal
• Parasympathetic stimulation
• CCK (cholecystokinin)
• Gastric hormones stimulate an
‘Anticipatory’ release of insulin
• Other hormones, eg glucagon, growth
hormone, cortisol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the major stimulation of adrenalin or epinephrine release (catecholamine)

A

Stress
• Threat, noise, excitement, high
temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How are catacholamine synthesized

A

• The catecholamines are synthesised

in sequence from tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Does catecholamines have negative feedback

A

No negative feedback loop. Action is
stopped mainly by degradation as
hormones have a short ½ life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the solubility of tyrosine

A

Hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Where are catecholamine synthesized

A

Cytosol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Where are catacholamine stored

A

Secretory (Chromaffin) Granules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

How to secrete catacholamine

A

Exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How are catecholamine transported

A

As a Free Hormone and Bound to

Plasma Proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Where are the receptors for catecholamine

A

Surface of Target Cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What does the catecholamine activate

A

Second Messenger System

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Where are amine hormones produced

A

thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the role of amine hormone

A

Regulate basal metabolic rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What does amine cleaved into

A

Cleaved to form pro-hormone
Thyroxine (T4) & active
Triiodothyronine (T3)

36
Q

What is the solubility of amine hormones

A 
Lipophilic amines, but polarity of the
iodine means active transport is
required across cell membranes
Lypophilic, but now known to be
actively transported into cells by
transporters (ATP-dependent
carriers)
37
Q

Where are amine hormones synthesized

A

Within large glycoprotein

thyroglobulin

38
Q

Where are amine hormone stored

A

Stored as thyroglobulin in

colloid follicles

39
Q

How are amine hormone excreted

A

exocytosis

40
Q

How are amine hormone transported

A

Mostly bound to Plasma Proteins

thyroxin-binding globulin

41
Q

Where is the receptor of amine hormone

A

Inside Target Cell

42
Q

What does amine hormone do

A

direct effect on genes

43
Q

What are the efffect of thyroid hormone

A 
1. Increased
metabolic rate
2. Increased
oxygen
consumption by
mitochondria
3. Nutrients
4. Thermogenesis
44
Q

How are T3 & T4 secretion regulated

A 
negative feedback,
• Thyrotropin releasing hormone (TRH)
formed in hypothalamus
• Response to blood levels T4/T3
• TRH is released into portal veins of
hypothalamic-hypophyseal tract
• Stimulates thyrotropes to release
TSH into blood
• TSH stimulates follicular thyroid cells
to produce and secrete T3 & T4
• As levels of T3/T4 rise, negative feed
back loops reduce synthesis of TRH
in hypothalamus (long arm) and
release of TSH in the anterior
pituitary (short arm)
45
Q

What are the prostanoid

A

prostagladins

thromboxanes

46
Q

What is the function of eicosanoid, Prostaglandins

A

• vasodilators

regulate blood flow

47
Q

What is the function of eicosanoid, Thromboxane A2

A

• induces platelet
aggregation
• promotes
vasoconstriction

48
Q

What is the function of eicosanoid, Leukotrienes

A
  • allergy involvement
  • neutrophil chemo-attractant
  • vascular permeability
49
Q

Whare are steroid hormone derived from

A

cholesterol

50
Q

What are some steroid hormones

A 
1) adrenal cortex (cortisol, androgens &
aldosterone)
 2) ovaries (estrogen and progesterone)
 3) testes (testosterone
 4) placenta (estrogen and progestero
51
Q

Where are steroid stored

A

Hormones Not Stored, Only Precursor
(Cholesterol) Stored
Stored (or its derivatives) in lipid droplets
within each steroidogenic or

52
Q

How are steroids produced

A 
.
 Produced through a series of enzymatic
reactions
 Cholesterol to pregnenolone
 (rate limiting step).
 Each steroidogenic organ can produce only
those steroid hormones for which it has a
complete set of
53
Q

what is the solubility of steroid

A

lipophilic

54
Q

How are steroid secreted

A

diffusion

55
Q

How are steroid transported

A

Mostly Bound to Plasma Proteins

56
Q

Where is the receptor of steroids

A

Inside of Target Cell

57
Q

What is the action of steroids

A

Direct Effects on Genes ® Production of New

Proteins

58
Q

What is the function of cortisol

A

Metabolic Actions Corticosteroids
Maintains blood glucose levels during
fasting & increases blood glucose
during stress

59
Q

What happens when there is an early fasting

A 
Cortisol 
1. Early fasting - defence against
hypoglycaemia.
• Increase plasma glucose
• Liver Increased glucose output
• Promotes gluconeogenesis,
glycogenolysis & lipolysis
60
Q

What happens during the late fasting stage

A

Cortisol

• build up of glycogen stores

61
Q

What Anti-inflammatory actions can cortisol do

A

Inhibits arachidonic acid production and

prostaglandins

62
Q

How are cortisol regulated

A 
• Negative feedback
regulation
 on pituitary and
hypothalamus by cortisol
• Long feedback loop
 on hypothalamus by ACTH
• Short feedback loop
63
Q

Where are oxytocin released

A

• Released by posterior pituitary
Oxytocin receptors are on smooth muscle cells
• mammary gland and uterine

64
Q

What is the role in oxytocin

A

so acts as a neurotransmitter in bra
s
1. Promotes milk ejection (milk let down) during lactat
oli
2. Uterine contraction during parturition

65
Q

How oxytoxin promote milk ejection

A

Milk initially secreted into alveoli (sacs) within mammary
gland
OCT stimulates contraction of myoepithelial cells (smooth
muscle cells) which surround alveoli

66
Q

How oxytoxin cause uterine contraction

A

on
Important in cervical dilation & uterine contractions
After birth maintains haemostasis & evacuation of
placenta

67
Q

how oxytocin is regulated

A 
Positive Regulation of Oxytocin
Secretion
1. Suckling
• Neurogenic reflex
to hypothalamus
2. Pregnancy and
Parturition
• Oxytocin receptors in
uterus increase
late trimester &
during labour
• Estrogen induced
• Uterus stretching -
--> more oxytocin
released
68
Q

What happens when there is a thyroid tumour

A

• Hyperthyroidism due to thyroid tumour – increased T3 & T

69
Q

What benign pituitary tumour do to cortisol

A

• Increased cortisol due to benign pituitary tumour – Cushing’s disease

70
Q

What is salbutamol made from

A

man-made

71
Q

What is the function of salbutamol

A

Dilates airways
May increase heart rate
Synthetic molecule

72
Q

What is atropine made from?

A

Plants

73
Q

What is the function of atropine

A 
Dilated pupils attractive 
Dry mouth, photophobia, 
hallucinations, death!
Deadly Nightshade
Atropa Belladonna
74
Q

What does drugs affect

A

chemical & electrical signalling

75
Q

What is agonist

A

Bind and

activate the receptor

76
Q

What is Antagonists

A

Bind and DO NOT

activate the receptor

77
Q

What is affinity

A

A quantifiable measure of the molecular

attraction to the receptor

78
Q

what is pharmacokinetics

A

What will happen to

the drug in the body?

79
Q

What is pharmacodynamic

A 
What effect(s) will the
drug have in the body?
80
Q

What is dose

A

• Amount administered
– in vitro: dose ~ concentration
– in vivo: dose = concentration

81
Q

What is concentration

A
  • Amount in given volume

* Amount at molecular target

82
Q

What is potency

A

• How much drug is needed for effect
– NOT the affinity
– NOT the size of the response

83
Q

What is efficacy

A

Ability of a drug to activate the receptor

84
Q

What does agonist mimic

A

endogenous molecules

85
Q

What is the role of antagonist

A

inhibit endogenous molecules

86
Q

What is the therapeutic range

A

optimise benefit/minimise risk

87
Q

How does Parasympathetic Sympathetic work together

A

they will try to balance each other

Cells to systems (25 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions