Chemical Coordination Flashcards Preview

General IGCSE Biology > Chemical Coordination > Flashcards

Flashcards in Chemical Coordination Deck (17)
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1

What is a gland

A gland is an organ that secretes substances

2

Two types of gland

Exocrine and endocrine

3

Exocrine

Secretes product through duct or tube

4

Endocrine

No duct or tube so they secrete it into the blood stream

5

Nervous system

Works by nerve impulses
Nerve impulses travel fast instant response
Response shorter
Act upon individual cells

6

Endocrine system

Works by hormones transmitting through blood
Travel slowly & take longer to react
Response longer
Widespread affect

7

Pituitary Gland

Follicle Stimulating Hormone - Egg/sperm develop
Luteinising hormone LH - Egg release, testosterone
ADH - Controls water
Growth Hormone GH - Speed up growth

8

Thyroid

Thyroxin-Metabolic rate

9

Pancreas

Endocrine and Exocrine gland
Insulin Lowers blood glucose
Glucagon Raises blood glucose

10

Adrenals

Adrenaline Prepares for activity

11

Testes

Testosterone Secondary sexual characteristics

12

Ovaries

Oestrogen Secondary female characteristics
Progesterone Menstrual cycle

13

Why/Where is adrenaline released

Frightened, angry, excited to prepare for action
Adrenal gland

14

What happens - Adrenaline 7

Pupils dilate - Visual sensitivity to movement
Breathing faster - Taking more oxygen
Heart faster- More blood/oxygen to the muscles
Hair on ends - Makes it look larger
Glucose is released - Muscles use for respiration
Blood diverted - Away from intestine to muscles
Mental awareness increase - Faster reaction

15

Where is glucose stored

Liver and insulin stimulates liver cells to convert it into glycogen.

16

Diabetes

Pancreas cannot make enough insulin to keep blood glucose constant.

17

Symptoms of diabetes

High glucose in urine
Constant Thirst