Simple Hormones & Homeostasis

Question 1

Compare contrast Endo- and Exocrine glands?

Answer 1

Endocrine glands secrete hormones into the bloodstream. Exocrine glands secrete other stuff (enzymes, oil, sweat, etc) into ducts(tubes). Both secrete things.

Question 2

Define a gland.

Answer 2

A gland is an organ in an animals body that synthesises a substance for release.

Question 3

Define Homones.

Answer 3

Chemical messages sent between body parts.

Question 4

What is the AKA of the hypothalamus and what does it do?

Answer 4

The “master nerve control center”. It works with the nervous system by receiving information from nerves about internal conditions and orders release of hormones from the pituitary gland.

Question 5

What is the AKA of the pituitary gland and what does it do?

Answer 5

The “master gland” belongs to the endocrine system and secretes a broad range of hormones

Question 6

What cells in the hypothalamus receive nerve impulses?

Answer 6

Neurosecretory cells

Question 7

How is a release from the pituitaries anterior gland stimulated?

Answer 7

Releasing hormonesreleased from the hypothalamus reach the anterior pituitary through the portal vein. When they reach the anterior pituitary, a diff hormone from the endocrine cells of the A pituitary gland is released and travels via blood to target organ.

Simple:
Hypothalamus,
releasing hormone-> anterior pituitary-> hormone

Question 8

what vein carries releasing hormones form hypothalamus to pituitary gland?

Answer 8

portal vein

Question 9

Anterior Pituitary Hormones:

Answer 9

Leutinizing Hormone (LH)
Follicle Stim. Horm. (FSH)
Prolactin
Growth Hormone

Question 10

What does Prolactin stimulate?

Answer 10

Promotes production of milk

Question 11

What does FSH stimulate?

Answer 11

Follicle Stimulating Hormone:
Stimulates the production of sperm and eghs

Question 12

What does LH stimulate?

Answer 12

Leutinizing Hormone stimulates the production of sex hormones by gonads.

Question 13

What are gonads?

Answer 13

They develop into testes and secrete testosterone.

Question 14

How is the secretion of hormones from the pituitaries posterior gland stimulated?

Answer 14

The neurosecretory cells in the hypothalamus project axons that end in the posterior pituitary. These axons store hormones. When triggered thy will secrete hormones directly into the blood.

Question 16

Which hormones does the posterior pituitary release?

Answer 16

Antidiuretic Hormone (ADH) and Oxytocin

Question 17

What does Oxytocin trigger?

Answer 17

The uterine contractions during childbirth

Question 18

What does ADH do?

Answer 18

Regulates osmolarity (water balance)

Question 19

Give an example of negative feedback.

Answer 19

Dehydration and the ADH hormone.

Chemoreceptors sense dehydration, this triggers release of ADH, ADH causes collecting duct to absorb more water. Hydrated.

Question 20

When is temperature too low?

Answer 20

Below 36 C

Question 21

When is temperature too high?

Answer 21

Aboce 38 C

Question 22

What is the control centre of internal temperature control?

Answer 22

Hypothalamus

Question 23

How does the body regulate cold internal temperatures?

Answer 23

The Thermoregulation centre in the Hyp. is activated. The nerves send messages to muscles to contract rapidly. AKA shivering. This creates heat and sweat, which increases temperatures.
Nerves also send messages to blood vessels. Blood Vessels constrict to minimise heat loss. (Vasoconstriction)

Question 24

What is the term for regulating internal temperatures?

Answer 24

thermoregulation

Question 25

How does the body regulate elevated temperatures?

Answer 25

**Thermoregulation center activates**, this is the the Hypothalamus. **Nerves** send messages to blood vessels. **Blood Vessels dilate** to reach surface so that **heat escapes**. (**Vasodilation**) Nerves also send signals to **sweat glands** to secrete sweat and then evaporate.

Question 26

What is the term for when blood vessels get smaller?

Answer 26

Vasoconstriction

Question 27

Wat is the control centre of regulating blood pH?

Answer 27

Medulla oblongata

Question 28

What i the term for regulating blood pH?

Answer 28

"acid-base regulation"

Question 29

When does the acid-base regulation activate?

Answer 29

When the pH is too low (acidic)

Question 30

How is the blood pH regulated?

Answer 30

Medulla oblongata recognises and increase in CO2. Nerves send messages to the diaphragm to increase breathing rate. This decreases CO2 and acidity.

Question 31

What in the blood makes it more acidic?

Answer 31

CO2 + H2O = H2CO3 (carbonic acid)

Question 32

What is the control centre of blood glucose regulation?

Answer 32

the pancreas

Question 33

What happens when blood glucose levels are too low?

Answer 33

** Glucagon** is released by the pancreas into the blood stream. When reaching the Liver, The alpha cells of the liver **break down glycogen** into **glucose**, releasing it into the blood.

Question 34

What happens when blood glucose levels are too high?

Answer 34

The pancreas releases the hormone **insulin**. Insulin goes through the bloodstream until it reaches the liver. This causes the liver to take up glucose by turning it into **glycogen**.