Bio paper 2 Flashcards
Difference between a conscious response and a reflex
Reflect skips out the brain and goes straight to effector
What do stimulants and depressants do and how do they work
Stimulant - energy drink. Increases rate of neurotransmitters
Depressants - alcohol. Decreases rate of neurotransmitters
What do glands do
They produce hormones that effect the function of organs
What’s the master gland and what does it do
Pituitary gland, secrets hormones and controls the other glands in the endocrine system
How does your body respond to high/low blood sugar levels
High) pancreas produces insulin which causes glucose to be absorbed into cells. excess glucose is converted to glycogen
Low) pancreas produces glucagon which causes the liver and muscles to convert glycogen into glucose
What do the hormones thyroxine
And adrenaline do
Thyroxine controls body’s metabolism
Adrenaline increases blood flow and breathing rate to prepare for “fight or flight”
What does FSH do
Caused an egg to mature and to ovaries to produce oestrogen
Found in the pituitary gland
What does oestrogen do
Causes uterus lining to thicken and causes the pituitary gland to secrete LH
What does LH do
Causes eggs to be released so it can travel to the uterus to fertilise with the sperm cell
What does progesterone do
It’s secreted by the overies and maintains the uterus lining
Describe the structure of DNA
Double helix polymer the contains genetic code
1 advantage for sexual reproduction
Off spring can become better adapted to environment
1 advantage of asexual reproduction
One one organism is needed to reproduce
Homozygous meaning
Genotype of 2 of the same alleles
Heterozygous meaning
Genotype of 2 different alleles
How do you estimate the population of an organism
1) place 1m quadrant in a random location and count the number of organisms
2) calculate average and multiply by total area
How do humans effect biodiversity
Deforestation for space for buildings
Why do pyramids of biomass always get smaller with each trophic level
Because energy is lost
What is a genotype and phenotype
Genotype is an organisms specific genetic code and phenotype is that code expressed physically
What is homeostasis
Maintenance of a internal environment to maintain optimum conditions for enzyme function
Example of conditions maintained by homeostasis in the body
Blood glucose conc
Body temp
Water levels
What 3 components do all control systems have
Receptors
Coordination centres
Effectors
Function of a receptor
To detect changes in the environment
Function of the coordination centres
Function of an effector
Bring about responses to stimuli
What is an effector made of
Muscles and glands
What does the CNS consist of
Brain and spinal cord
What is blood glucose levels controlled by
The pancreas
How to treat type 1 diabetes
Insulin injections
How to treat type 2 diabetes
Exercises regime
Difference between selective breeding and genetic engineering
Selective breeding takes generations to happen
Genetic engineering sees results in one life time
