Need 2 know Flashcards
(18 cards)
What does Pituitary Gland do
Sends signals to other glands
What does the Thyroid do
Controls growth, metabolism
What does the Pancreas do
Secretes insulin (+ glucagon) to control blood sugar
What do the adrenal glands do
Release adrenaline
What do the Testes do
Produce sperm
What do the Ovaries do
Release eggs and secrete hormones
Properties of Thyroxine
Secreted by Thyroid controls metabolic rate
Low - hypothalamus in brain releases TRH causes pituitary glands to release TSH thyroid releases more thyroxine
Mieosis
1) Chromosomes in diploid cell copied
2) similar chromosomes pair up and genes swapped between them
3) cell divides to produce two diploid cells
4) These divide to produce 4 haploid cells (gametes)
What is a Gene
Portion of DNA that codes for a protein
What is a genome
Entire Genetic Code in an organism
Genetic Engineering
1) Desired Gene is cut from another organisms DNA using enzyme
2) Gene inserted into a vector (bacteria)
3) Vector inserts gene into cells of another organism in early development
4) Organism develops with desired characteristic due to cell synthesising that protein
Centra Nervous System
Receptors - cells that detect stimuli
Sensory Neurones carry info from receptors to CNS
CNS sends information to effectors along motor neurones
Properties of Sensory Neurones
Neurones that carry infomation as electrical impulses from CNS to effectors
Properties of Motor Neurones
Neurones that carry electrical impulses from CNS to effectors
Properties of Effectors
All your muscles and glands which respond to nervous impulses
Negative Feedback System
1) Receptor detects a stimulus - level is too high
2) Coordination Centre receives and processes the information then organises a response
3) Effector produces a response which counteracts the change and restores the optimum level - level decreases
What is Homeostasis
The regulation of conditions inside your body to maintain a stable internal environment
Menstrual Cycle
Stage 1) Day 1 - uterus lining breaks down for 4 days
Stage 2) over 10 days uterus lining builds up again into a thick spongy layer of blood vessels , ready to receive fertilised egg
Stage 3) An Egg develops and is released from ovary at day 14 (ovulation)
Stage 4) Wall is then maintained for about 14 days until day 28, if no fertilised egg has landed on the uterus wall by day 28 spongy lining starts to break down
