Brainscape's Knowledge GenomeTM

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


See full index

Biology 6th Form OCR A (missing exchange systems) > Module 5: Hormonal Communication > Flashcards

Module 5: Hormonal Communication Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Effects of peptide hormones:

A

Fast changes in protein activity though sometimes changes to gene expression may occur

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

What is a hormone?

A

A hormone is a chemical messenger that is transported via the bloodstream to act on target cells.

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

Major Endocrine Glands:

A

Pituitary Gland, Pineal gland, Thyroid Gland, Pancreas, Adrenal gland, Ovary, Testis

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

Pineal Gland:

A

Pineal Gland produces melatonin - functions biological clock

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

Pituitary Gland:

A

FSH/ LH, ADH, growth hormone, oxytocin, prolactin - multiple functions.

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

FSH/LH

A

Found in the ovaries and aids menstrual cycle

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

ADH:

A

Kidneys - osmoregulation

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

Growth hormone:

A

many target organs -> growth and division.

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

Oxytocin:

A

Uterus - birth contractions

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

prolactin:

A

breast tissue - milk production

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

Thryroid Gland:

A

Produces thyroxin which controls metabolic rate in the liver.

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

Adrenal Glands:

A

Produces Adrenaline and cortisol which target many organs.

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

Testes:

A

testosterone targets many organs to develop male characteristics.

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

Ovaries:

A

Estrogen/ progesterone - target uterus and control menstrual cycle.

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

What are the 3 types of hormones?

A

Steroid hormones, peptide hormones and amino acid derivatives.

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

Steroid Hormones:

A

Lipophilic so can freely diffuse across the plasma membrane.
Bind to receptors in either cytoplasm or nucleus.
Forms receptor-hormone complex which moves into the nucleus and stimulates/inhibits transcription.

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

Peptide Hormones:

A

Hydrophilic so cannot freely cross the plasma membrane.
Bind to receptors on the cell surface membrane.
Activates a series of intracellular molecules (second messengers) that regulate cell activity through a cascade reaction.

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

Amine Hormones:

A

Derived from amino acid tyrosine.

They don’t all share identical properties.

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

Synthesis of Peptide Hormones:

A

Sythesised as prohormones which must then be activated

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

Synthesis of Steroid Hormones:

A

Synthesised in a series of reactions of from cholesterol.

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

Synthesis of Amino acid derivative Hormones:

A

Synthesised from the amino acid tyrosine.

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

Storage of Peptide hormones:

A

Stored in vessicles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Storage of Steroid hormones:

A

Not stored- released immediately

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

Storage of Amino acid derivatives hormones:

A

Stored before release (storage mechanism vessicles)

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

Solubility of Peptide Hormones:

A

Tend to be polar and water soluble, travelling freely in the blood.

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

Solubility of steroid hormones in water:

A

Non-polar and require carrier proteins to travel in the blood.

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

Solubility of amino acid derivative:

A

Some are polar and others must be protein-bound.

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

Receptors of peptide hormones:

A

Bind to receptors on cell surface membrane and stimulate the release of second messenger molecules

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

Receptors of steroid hormones:

A

Bind to intracellular receptors to change gene expression directly.

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

Effects of steroid hormones:

A

Alterations in gene expression, slower onset with long duration.

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

Effects of Amino Acid derivative hormones:

A

Adrenaline functions like peptides. Thyroid hormones act similar to steroids.

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

Adrenal Cortex:

A

Produces hormones vital to life.
Produces steroid based hormones.
Controlled by hormones secreted by pituitary gland.

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

What are the 3 groups of hormones released by the adrenal cortex?

A

Glucocorticoids, Mineralocorticoids, Androgens

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

Adrenal Medulla:

A

Produces non-essential hormones (adrenaline and noradrenaline (neurotransmitter))
Produces amine based hormones.
Triggered by sympathetic stimulation.

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

Where is the pancreas located?

A

Located to the rear of the bottom half of the stomach.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the two types of function of the pancreas?

A

Endocrine and Exocrine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the exocrine function of the pancreas?:

A

To secrete a variety of digestive enzymes and alkaline pancreatic juice into the pancreatic duct to the duodenum.

38
Q

What is the endocrine function of the pancreas?:

A

To secrete glucagon, insulin, somatostatin, and pancreatic polypeptide into the blood via fenestrated capillaries.

39
Q

On a micrograph what is the appearance of islets of Langerhans?

A

Lightly stained, large spherical clusters.

40
Q

On a micrograph what is the appearance of pancreatic acini?

A

Darker stained, small berry-like clusters.

41
Q

What is the name of the cells on the inside of a duct at the acini?

A

centroacinar cells

42
Q

What is the purpose of the many fenestrated capillaries permeating islets of Langerhans?

A

Quick diffusion of pancreatic hormones into the blood.

43
Q

What separates the islets of Langerhans from the Acini?

A

A delicate sheath of reticular fibres

44
Q

What kind of staining method is used to differentiate between alpha and beta cells in pancreatic islets?

A

Differential Staining, because standard techniques is less clear.

45
Q

Beta cells:

A

Filled with insulin granules.

Secrete insulin

46
Q

Alpha cells:

A

Filled with glucagon granules. Secrete glucagon, larger than beta cells and located peripherally in the islet.

47
Q

What are the “White gaps” between cells?

A

Connective tissue (Don’t draw large gaps between cells)

48
Q

What is the most common effect of diabetes?

A

Hyperglycaemia (blood glucose level above safe range)

49
Q

What are the three ways in which glucose enters the bloodstream?:

A

Absorption in the gut following carbohydrate digestion.
Hydrolysis of glycogen stores.
Non-carbohydrates (e.g lipids, lactate and amino acid) into glucose.

50
Q

Why does the amount of glucose absorbed into the blood from products of digestion vary substantially?

A

Some meals are much more carbohydrate-rich.

51
Q

Without meals do blood glucose levels still fluctuate?

A

Yes, they fluctuate around a set point.

52
Q

Why do blood glucose levels fluctuate?

A

Blood glucose levels are constantly changing as blood glucose is being absorbed by skeletal muscle tissue and released at the liver and adipose tissue. Furthermore, insulin and glucagon are worked as a part of a negative feedback mechanism.

53
Q

Why does glucose need to be in the blood?

A

To be transported to cells to provide glucose for cellular respiration to produce ATP.

54
Q

Why is Hyperglycaemia harmful?

A

The high glucose levels cause the tissue fluid to be hypertonic to the blood, causing water to leave cells into the blood, damaging cells and also reducing chemical reactions.

55
Q

What is the name of the process where glycogen is broken down in the liver to release glucose?

A

Glycogenolysis.

56
Q

What is the name of the process where glucose is made from non-carbohydrate sources?

A

gluconeogenesis.

57
Q

Where are glucagon receptors located?

A

Liver and fat cells.

58
Q

What two responses to glucagon slow down the decrease of blood glucose levels?

A

Reducing the absorption of glucose into liver cells.

Decreasing the rate of glucose breakdown (by decreasing the rate of cell respiration)

59
Q

Summary outline of the link between cell signaling and glucagon:

A

Alpha cells secrete glucagon. Glucagon binds to receptors on the cell surface membrane of liver cells, causing a conformation change. The confirmation change activates a G-protein which activates an enzyme that catalyzes the production of a second messenger. This leads to a cascade of reactions leading to the breakdown of glycogen into glucose.

60
Q

What cells have insulin receptors?:

A

Most cells.

61
Q

Why, after cells have let in lots of glucose, must the cells use/ dispose of the glucose?:

A

The cells will become hypertonic to the blood, risking cell lysis. Therefore the cells try to “use up” the glucose to reduce this risk.

62
Q

How does insulin reduce blood glucose levels?:

A

It increases the absorption of glucose into cells, by increasing cell surface membrane permeability to glucose.
Insulin also activates enzymes within liver and adipose cells that convert glucose into glycogen.
Increases the rate of glucose breakdown (higher respiration rates)

63
Q

What is Glycogenesis?

A

The conversion of glucose into glycogen.

64
Q

How does insulin increase the uptake of glucose into cells?

A

Insulin binds to specific receptors on the membranes of target cells. This releases a chemical signal which stimulates the production vesicles lined with glucose transporter proteins. These vesicles fuse with the cell surface membrane, increasing the permeability of the cell to glucose. This increases the rate of facilitated diffusion.

65
Q

Outline the stages of events leading to the secretion of insulin.

A

Concentration of blood glucose is high -> Glucose molecules enter the Beta-cell by facilitated diffusion -> the cell respires the glucose to produce ATP - > ATP causes the K+ channels to close -> prevent K+ ions from leaving cell -> depolarises membrane -> voltage-gated Ca2+ channels open -> influx of Ca2+ ions causes insulin-containing vesicles to move towards the membrane, where they fuse through exocytosis and release insulin into the capillaries.

66
Q

What is the increased thirst experienced by diabetes sufferers caused by?

A

Cells don’t have enough water due to blood’s hypertonicity.

67
Q

What is the increased urination experienced by diabetes sufferers caused by?

A

The hypertonicity of the water compared to surrounding tissues, increases the water content of the blood -> Excess water in blood leads to less ADH production -> less water is retained in DCT and collecting duct

68
Q

Acute (short term/ fast-acting) complications of Diabetes:

A

Diabetic ketoacidosis, hyperosmolar hyperglycaemia, or death.

69
Q

Chronic complications of Diabetes:

A

Cardiovascular disease, stroke, chronic kidney disease, foot ulcers, and damage to eyes.

70
Q

Diabetes Type 1:

A

Insulin is not produced by Beta cells.
Cannot detect high levels of glucose or release insulin.
Lack of insulin affects glycogen stores, causing fatigue.
Unknown cause - potentially autoimmune?
Treated with insulin injections.
Usually occurs during childhood.

71
Q

Diabetes Type 2:

A

High glucose + high insulin levels have caused the body to become resistant.
Associated with inactivity, excess weight, consumption of refined carbohydrates.
Treated with medication, insulin injections, or control of diet.

72
Q

On a blood-glucose concentration graph what does a slow decrease tell you?

A

The person is likely diabetic.

73
Q

How does type 2 diabetes occur?

A

Prolonged overproduction of insulin leads to desensitisation of insulin receptors and-so (more) glucose is not removed from the bloodstream.

74
Q

Treating Diabetes: Pancreas Transplant

A

80% successful in removing the symptoms, however donor organs are rare.
Injected Beta Cells have an 8% success rate, immunosuppressant drugs eventually stop cells producing insulin.

75
Q

Advantages of Stem cells for treating diabetes:

A

Overcomes donor organ problem, reduced cell transplant rejection, insulin injections abundant.

76
Q

Disadvantages of Stem cells for treating diabetes:

A

destruction of human embryos, injected stem cells could become cancerous tumours, due to limited ability to control them.

77
Q

Adrenocortical system:

A

Release of longer term stress hormones from the adrenal cortex is coordinated by hormones from the pituitary gland. This occurs when the hypothalamus stimulates the pituitary gland to secrete ACTH.

78
Q

Sympathetic System:

A

Stimulates adrenal medulla to release stress hormones.

79
Q

Fight or Flight: Step 1

A

Autonomic nervous system detects a threat.

80
Q

Fight or Flight: Step 2

A

Hypothalamus communicates with the sympathetic nervous system, and the adrenal cortical system.

81
Q

Fight or Flight: Step 3

A

The sympathetic nervous system uses nervous impulses to stimulate the adrenal medulla, glands and smooth muscle to respond appropriately.

82
Q

Fight or Flight: Step 4

A

Hypothalamus communicates with pituitary gland.

83
Q

Fight or Flight: Step 5

A

Pituitary gland releases ACTH

84
Q

Fight or Flight: Step 6

A

Stimulates the adrenal cortex to release cortisol and corticosterone.

85
Q

Corticosterone:

A

Suppresses the immune system and inflammatory responses.

86
Q

Cortisol:

A

Increases blood pressure, increase blood sugar, suppresses immune system.

87
Q

Adrenaline (Physical properties):

A

Polar (hydrophilic), amino acid derived hormone.

88
Q

Action of Adrenaline:

A

Adrenaline binds to complimentary receptors.
This activates the enzyme adenyl cyclase via an anchored g protein.
This catalyses the reaction of ATP into cAMP, which acts as a secondary messenger and activates protein kinases, which phosphorylate other enzymes.
The glycogen then undergoes glycolysis into glucose.

89
Q

Action of adrenaline in cardiac tissue.

A

Depolarises the cell membrane of SAN cells.

90
Q

Basal Heart Rate:

A

The heart rate resulting form the myogenic pacemaker cells.

91
Q

Effects of Adrenaline:

A

Increases heart rate, blood glucose concentration levels.

92
Q

Noradrenaline as a hormone:

A

Increases heart rate, widens pupils, widening air passages in the lungs and narrowing blood vessels near non-essential organs.

Biology 6th Form OCR A (missing exchange systems) (27 decks)

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