B10 And 11 Flashcards
Homeostasis
homeostasis in the regulation of the internal conditions of a cell or organism to maintain optimum conditions for function in response to internal and external changes.
What is controlled by homeostasis
control of blood glucose concentration
body temperature
water levels
Types of control systems
Nervous System-Electrical
Endocrince System-Hormonal/Chemical
Nervous Response
Controlled by electrical impulses that travel through the neurons
Chemical Response
Controlled by hormones travelling through the bloodstream
What is the nervous system made up of
Central Nervous System
Peripheral Nervous System
Central Nervous System
Consists of brain and spinal cord
Peripheral Nervous System
Controls involuntary actions via peripheral nerve
Types of neurons
Sensory
Relay
Motor
How is a neuron adapted for its function
Dendrites that branch out
Long Axon
Myelin Sheath for insulation
Path of an electrical impulse
Stimulus-receptor-sensory neuron-CNS-motor neuron-effector-response
Synapse
Gap between 2 neurons
How does an electrical impulse cross a synapse
Once the electrical impulse reaches the first neuron, stimulation of neurotransmitter chemicals release which bind to the second neuron and copies the message of the first neuron on to the second neuron.
Reflex Actions
Inbuilt involuntary response to a stimuli controlled by PNS
What is the endocrine system
Second coordination control system of the body consisting of glands
Pathway in the endocrine system
Gland-hormone-bloodstream-target organ-response
What is a hormone
Is a chemical produced by a gland which travels through the bloodstream and carries out a response
What does the pituary gland secrete
FSH (follicle stimulating hormone)
LH (leteunising hormone)
ADH (anti dieuretic hormone)
What does the thyroid gland secrete
Thyroxine
What do the adrenal glands secrete
Adrenaline
What does the pancreas secrete
Insuling and glucagon
What do the ovaries secrete
Oestregen and Progesterone
What do the testes secrete
Testosterone
What does FSH do
Stimulates maturation of the egg
What does LH do
Stimulates ovulation of the egg
What does thyroxine do
Control metabolic reactions
What does insulin do
Lowers glucose levels
What does glucagon do
Raises blood sugar levels to homeostatic levels
What does adrenaline do
Fight or flight response
What does oestrogen do
Stimulates build up of the uterus lining
What does progesterone do
Maintains the uterus lining in case of egg being fertilised
What does testosterone do
Controls puberty in males
Hormones in women acronym
Fsh
Oestrogen
Lh
Progesterone
What is the difference between nervous and endocrine system
Nervous is electrical whereas endocrine is hormonal
Which organ detects blood sugar levels
Pancreas. If blood sugar is low glucagon is released if high insulin is released
Type 1 diabetes
Where the body fails to produce enough insulin
Type 2 diabetes
Where the body produces insulin but no response is given
How is type 1 diabetes caused
By birth or heritage
How is type 2 diabetes caused
By lifestyle
Cures of type 1 diabetes
Humalin a genetically engineered bacteria
Insuling pump
Cures for type 2 diabetes
Drugs to enhance the effect of insulin on the body
Low carb diet
Regular exercise
Negative feedback
Is an important type of control found in homeostasis. It responds to a change and tries to regulate it back to homeostatic levels
General stages in negative feedback
If a level of something rises it tries to decrease it
If a level of something lowers it tries to increase it
Conditions controlled by negative feedback
Thermoregulation
Blood sugar regulation (insuling when high glucagon when low)
Thyroxine
Controls the rate of metabolic reactions
Adrenaline
Stimulus for the fight or flight response produced in times of stress
Effects of adrenaline
Increased heart rate and breathing rate for oxygen and glucose for respiration
Pupils dilate to let more light in
Hormonal contraceptive methods
The pill
Contraceptive injection
The coil
Non hormonal contraceptive methods
Barrier methods
Spermicides
Abstinence
Surgical methods
Causes of infertility
Low sperm count
Obesity
Eating disorders
Increasing maternal age
Which hormones are used in fertility treatment
FSH
LH
Stages of IVF
- Involves giving mother fertility drugs
- The eggs are collected and fertilised by sperm from the father
- The fertilised egg is developed into embryos
- When the embryos mature enough they are inserted back into the mother as a normal baby would
Disadvantages of IVF
Emotionally and physically stressful
The success rates are not high
