Human Endocrine system Flashcards Preview

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Flashcards in Human Endocrine system Deck (25):
1

Homeostasis

Maintaining a constant equilibrium or balance in the body despite changes in the internal or external environment

2

Hormones

Organic compounds
Chemical messengers
Secreted bu endocrine glands

3

Endocrine glands

-Ductless glands
-Release secretions(hormones) directly into bloodstream
-Blood transports hormones to target organs where they perform their function

4

Exocrine glands

-Glands that release secretions via ducts
-To a body cavity or
-To the outside

5

Examples of exocrine glands

-Tears
-Salivary glands that secrete saliva into ducts that open in the mouth cavity

6

Steroids

Lipid like organic compounds

7

Most hormones are ----
Some are -----

Proteins
Steroids

8

Target organ

organ that is affected by a specific hormone
Has receptors for this hormone, enabling it to respond

9

Two ways the hormones' regulatory function can be

1. stimulating
2. inhibiting

10

Negative feedback mechanism

Any deviation from the normal levels elicits a response that restores the normal levels

11

Hypothalamus

-part of brain just below corpus callosum
-controls functions of hypophysis
- link between the in nervous and endocrine systems

12

Anterior lobe of hypophysis

Adenohypophysis

13

Posterior lobe of hypophysis

Neurohypophysis

14

Why is pituatary gland the master gland

It secretes many hormones that affect many of the other endocrine glands

15

List 2 ways in which the hypothalamus is connected to the hypophysis

1. BY blood vessels to the anterior lobe
2. By neurons to the posterior lobe

16

Relationship between hypophysis and hypothalamus

hypothalamus produces hormones which are transported via neuron to posterior lobe of hypophysis for storage

17

How does the hypothalamus control the hypophysis

-Secreating releasing factors
1. via neurons (to posterior lobe)
2. Via blood (to anterior lobe)

These releasing factors stimulate the hypophysis to produce or release more hormones into the blood.

18

Releasing factors in hypophysis

These releasing factors stimulate the hypophysis to produce or release more hormones into the blood.

19

5 hormones secreated by the anterior lobe

1. TSH (thyroid stimulating hormone)
2. Growth hormone (SH / somatotropic hormone)
3. FSH (follicle stimulating hormone)
4. LH (Luteininsing hormone)

20

Dwarfism

The under-secretion of growth hormone.
Body = short body parts, arms torso and legs
= normal sized heads

21

Gigantism

Over secretion of growth hormone
Usually the result of a tumor i the hypohysis

22

Acromegaly

-Over secretion of growth hormone in adults
-Long bones in the body cannot lengthen anymore
-Growth plates in the epiphysises of the long bones close during puberty
-Bones of the face: jawbone, hands feet increase in size

23

2 hormones secreted by the posterior lube

1. ADH = antidiuretic hormone ---> prevents dehydration
2. Oxytocin

24

Where ADH produced and transported

-Hypothalamus
- transported to posterior lobe of hypophysis via neurons for storage

25

Function of ADH

Promote re absorption of water (through renal tubes in the kidney