Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Bio Module 5 > Hormonal Communication > Flashcards

Hormonal Communication Flashcards

1
Q

What is the pathway of hormonal communication?

A

Stimulus -> Receptors -> hormone -> effectors -> response

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

What is an endocrine gland?

A

It is a group of specialised cells that secrete hormones DIRECTLY into the bloodstream

Eg. Adrenal gland, pituitary gland

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

What is an exocrine gland?

A

It has a duct through which chemicals are released

Eg. Bile duct, sweat glands, pancreas

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

Effects of steroid hormones on the cell:

A

Pass through lipid component of the cell as they are hydrophobic

They then bind to steroid hormone receptors to form a hormone-receptor complex which attaches to DNA and acts as a T.F

These receptors can be found in the cytoplasm or the nucleus

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

Effect of non-steroid hormones on the cell:

A

Can’t pass through cell membrane as they’re hydrophilic

Binds to specific receptors in the surface of the target cell’s membrane

They activate an enzyme which causes the release of a second messenger (cAMP).

This triggers a cascade of enzyme-controlled chemical reactions

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

What is the method of transmission in the endocrine system?

A

Through the bloodstream

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

What is the speed of transmission in the endocrine system?

A

Slow

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

What is the length of effect in the endocrine system?

A

Long - until hormone is broken down

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

What are the 2 major roles of the pancreas?

A

Synthesise digestive enzymes
Controls blood glucose levels

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

What are the 3 most important digestive enzymes produced by the pancreas?

A

Amylases
Proteases
Lipases

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

What is the exocrine tissue in the pancreas?

A

The acini.

Each acini has a central duct into which digestive enzymes are secreted. The ducts join up the main pancreatic duct which is released into the small intestine.

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

What is the endocrine tissue in the pancreas?

A

The Islet of Langerhans.

Each Islet of Langerhans is the supported with a capillary network. Hormones are secreted directly into the blood via these capillaries.

Alpha and beta cells are found here

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

Which two cells are found in the islet of langerhans and what does each type of cell produce?

A

Alpha cells - produce glucagon

Beta cells - produce insulin

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

What concentration is glucose normally maintained at in the blood?

A

90mg per 100cm3

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

What is glycogenolysis?

A

Glycogen is split into glucose

Blood glucose conc. increases as a result

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

What is gluconeogenesis?

A

New glucose molecules are made from non-carbohydrate sources

Eg. Glycerol and amino acids

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

What is glycogenesis?

A

Glucose is converted to glycogen

Glucose conc. falls

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

In which ways is blood glucose conc. maintained?

A

Respiration
Exercise
Glycogenesis

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

What type of hormones are insulin and glucagon?

A

They are Antagonistic hormones which means they work against each other

20
Q

What type of feedback is used to regulate blood glucose conc. ?

A

Negative feedback

21
Q

What makes up the adrenal glands?

A

The medulla (inner part) and the cortex (outer part)

22
Q

What two types of stimuli trigger hormone secretion?

A

The arrival of an electrical impulse

Changes in concentration

23
Q

What are the 3 types of hormones produced in the adrenal cortex?

A

Glucocorticoids
Mineralocorticoids
Androgens

24
Q

What do glucocorticoids do and name and example?

A

Eg. Cortisol

They help the metabolism of carbohydrates and fats in the liver, stimulating the breakdown of proteins and fats into glucose.

Cortisol is released in response to stress as a result of low blood glucose

25
What are the functions of mineralocorticoids and name an example?
Eg. Aldosterone Maintains blood pressure by controlling sodium & potassium concentrations in the blood by acting on cells in the distal convoluted tubule and collecting duct. Causes increased reabsorption of Na, Decreased reabsorption of K and increases water retention
26
What are the functions of androgens?
They regulate secondary sexual characteristics (steroid-based) Important in females after menopause
27
What two hormones does the adrenal medulla release?
Adrenaline and noradrenaline
28
What are the effects of adrenaline?
(Non-steroid) Increases heart rate, quickly sending blood to brain and muscles. Rapidly increases glucose conc. by converting glycogen to glucose in the liver
29
What is the role of noradrenaline?
Works with adrenaline in response to stress widens airways, widens pupils and vasoconstriction of blood vessels to non-essential organs
30
Why may blood glucose conc. increase?
Diet - eating carbohydrate rich foods Glycogenolysis - glycogen is split into glucose Gluconeogenesis - new glucose molecules are made from non-carbohydrate sources eg. Glycerol
31
How may blood glucose conc. decrease?
Respiration - some glucose is used Exercise - more glucose is needed to release energy for muscle contraction Glycogenesis - glucogen —> glycogen
32
What type of hormones are insulin and glucagon?
They are antagonistic hormones meaning the work against each other
33
What type of feedback is used to regulate blood glucose conc. ?
Negative feedback
34
How is insulin secretion controlled when blood glucose conc. is low?
When blood glucose conc. is low then potassium ion channels remain open and calcium channels are closed Potassium ions leave the cell whilst calcium ions are unable to enter Cell has a potential difference of -70mV
35
What cells detect when blood glucose conc. is too high?
Beta cells in the islet of Langerhans of the pancreas produce insulin and release it into the bloodstream
36
What happens when blood glucose conc. is too high?
1) Glucose molecules move into the beta cell via a glucose transporter in the cell membrane 2) glucose is metabolised in the mitochondria, producing ATP 3) this excess ATP causes potassium ion channels to close (they are phosphorylated). 4) this causes a change in p.d across the membrane -70mV to -30mV causing depolarisation 5) this depolarisation causes calcium ion channels to open and calcium ions begin to diffusing into the cell 6) this increase in calcium ions stimulate (secretory) vesicles containing insulin to fuse with the cell membrane 7) insulin is then released by exocytosis into the bloodstream
37
What is the action of insulin?
1) insulin binds to receptor molecules on the surface of body cells. This increases the rate of glucose absorption - especially in liver and muscle cells 2) insulin stimulates an increase in glycogenesis (glucose —> glycogen) and glucose conversion to fat. 3) the effects of insulin cause blood glucose conc. to fall
38
What is diabetes?
An inability to control blood glucose concentration
39
What are some symptoms of diabetes?
Excessive thirst, blurred vision, high blood sugar
40
What is type 1 diabetes?
Genetic Patients unable to produce insulin due to faulty beta cells. Autoimmune response that normally develops in childhood
41
What is type 2 diabetes?
Caused by Lifestyle Patients can produce insulin but may not properly respond to it or are unable to produce enough. Often malfunctions on insulin receptors. Symptoms are similar to type 1 but develop slower and are less severe. Risk increases with age
42
What are the consequences of an insufficient quantity of insulin?
Excess glucose isn’t removed quickly No glycogen store Hypoglycaemia as glucose conc. in cells are low
43
What are the risk factors for type 2 diabetes?
Obesity High sugar diet Sedentary lifestyle Family history Asian or Afro-Caribbean heritage
44
Where are adult stem cells usually sourced from?
Bone marrow and placenta
45
Why is insulin produced by genetically engineered bacteria and not from pigs?
Less chance of rejection Lower chance of infection Cheaper to manufacture than extract Less ethical/moral objections
46
What is negative feedback?
Negative feedback is when any deviation from the normal values are restored back to their original, optimal level

Bio Module 5 (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions