Studied by 31 PeopleTags & Description
Do substances move into and out of cells?
true
What is homeostasis
the ability for organisms to maintain a steady sate when the external environment changes
what are examples of homeostasis
sweating or shivering
what is set point?
a normal or target value
what is normal range?
a range of values, around the target value, that are normal or healthy
what system closely monitors and coordinates
the endocrine system and the nervous system
what does the nervous system control
all body activities
what does the endocrine system do
it secretes hormones that regulate activities that the nervous system controls
what does the organ system do
it supplies body cells with all the substances, they also keep temperature pH, and other conditions at the optimal levels
what is the respiratory system
high concentration of carbon dioxide in the blood --> triggers faster breathing --> lungs exhale more --> removes carbon dioxide from the body fast
what is the excretory system
low level of water in the blood --> triggers retention in kidneys --> kidneys produce more concentrated urine --> less water lost from body
what is the endocrine system
high concentration of sugar in the blood --> triggers secretion of insulin from pancreas -->
what is insulin
hormone that helps cells absorb sugar from the blood
what is negative feedback
response to a stimulus that keeps a variable close to a set value, it shuts off or turns on.
what are the steps of negative feedback
a change in the body is detected --> temp or gluc level
a message is sent to a gland or organ
a response is initiated --> body returns to normal state
is negative feedback involved in the maintenance of blood sugar
true
what hormone is released when there is a rise in blood sugar levels
insulin which comes from the pancreas
whats is positive feedback
when a change from normal state triggers a reaction that results in the change being amplified
what is an example of positive feedback
contraction :D
what does the kidney do
filter blood, remove nitrogenous waste, regulate salt and water balance, regulate sugar levels
what are receptor cells
receptor cells are a nerve cell that identifies change in the environment both inside and outside the body
chemoreceptor
a sensory receptor that responds to chemical stimuli (tongue)
photoreceptor
a receptor that responds to light (eye)
mechanoreceptor
responds to pressure or distortion (skin, inner ear)
thermorecepetor
responds to heat (skin)
what is the nervous system
senses the environment, controls action
what does the central nervous system consist of
the brain and spinal cord
what does the central nervous system respond to
muscles and glands
what does the peripheral nervous system consist of
the bundles of nerves that relay messages between the sense organ, central nervous system and the muscles and glands.
where is the peripheral nervous system located
it is spread out through the entire body
what are neurons
cells that transmit messages in the form of electrical signals from the central nervous system.
what is a cell body
where the nucleus is located
what are denrites
branches that receive messages
what are axon
a thread like structure that carries impulses to other neurons
what are myelin sheaths
a fatty later that sometimes insulates the axon and sometimes a dendrite.
general structure of a neuron
general structure of a neuron
what so the sensory neuron do
transmit messages from the sensory organs to the central nervous system
what does the interneuron do
transmit messages from sensory neurons to motor neurons
what does the motor neuron do
transmit messages from the central nervous system to effectors such as muscle and glands to initiate a response.
what is the speed of messages in the endocrine system
slow, generally takes longer to have an effect
what is the speed of messages in the nervous system
fast, generally has a rapid effect
what is the length of response for the endocrine system
often long lasting
what is the length of response for the nervous system
usually short lived
what is the spread of effect in the endocrine system
the hormones travel to all parts of the body via the bloodstream. BUT only affect the receptors for that particular hormone
what is the spread of effect in the nervous system
very localised
how do messages travel through the body in the endocrine system
in the blood stream
how do messages travel through the body in the nervous system
along nerves
what type of messages in the endocrine system
hormone (chemical)
what type of messages in the nervous system
electrical impulse, neurotransmitter (chemical)
adrenaline
source gland --> adrenal target --> whole body main effects --> increases heart rate shuts down digestion makes energy available to muscles
thyroxine
source gland --> thyroid target --> whole body main effects --> makes cells consume more oxygen and nutrients increases body temperature
thyroid-stimulating hormone
source gland --> pituitary target --> thyroid main effects --> stimulates thyroid hormone production
follicle-stimulating hormone
source gland --> pituitary target --> gonads (ovaries or testicles) main effect --> stimulates egg production in females stimulates sperm production in males
what is the sugar the body relies on for energy
glucose
glucose levels in the blood need to be kept within a certain range for the body to maintain homeostasis
true
what happens if there is too much glucose in the body
insulin yay :D —> it is produced by the pancreases
what is it called if the body can't use insulin effectively
diabetes
what is type 1 diabetes
the pancreas can’t produce enough insulin to control blood glucose levels
what do people with type 1 diabetes need
regular injections of insulin
what is type 2 diabetes
the target cells of insulin stop responding properly —> insulin resistance
what do people with type 2 diabetes need to do
change diet
what is artificial insemination
injection of sperm into the women’s uterus close to to time of ovulation
where else has artificial insemination been used for besides humans
It has also been used in agriculture in the production of prime farm animals, and in the breeding programs for endangered species
what is In-vitro fertilisation (IVF)
It is when the egg and semen are combined outside the mother's body in a dish.
what can be done if a man does not have enough sperm or a woman does not have enough eggs for a reproductive technology.
they can get it from a donor :D
what is the controversy surrounding reproductive technology
some people believe it goes against nature
religion may play a part in determining someone's views
its very expensive
Donors do not get paid
what is a pathogen
an organism which causes a disease to its host
what are organisms which can only been seen with a microscope
microbes
are pathogens infectious diseases
yup
what is a macro parasites
they are multicellular, do not typically multiply but instead produce transmission stages.
what is fungus
they are unicellular, they reproduce
what is protozoan
are single- celled organisms whose DNA is inside a membrane-bounded nucleus
what is bacterium
single celled organisms whose DNA is not contained inside a membrane-bounded nucleus
what is a virus
can not reproduce unless inside a host cell
what is a prion
are thought to be incorrectly folded proteins
can a disease disrupt the normal homeostasis of your body
yes
what is a non-infectious disease
they are not caused by pathogens and can NOT be transmitted from one organism to another.
how can infectious diseases be spread?
sneezing, coughing, physical contact with an infected organism, contaminated objects, contaminated water supply or vectors
is the common cold an infectious or non-infectious disease
infectious disease
is cancer and infectious or non-infectious disease
non-infectious disease
what is the first line of defence also known as
the barrier defences
what does the first line of defence do
prevents pathogens from entering the body. it consists of both physical and chemical barriers
what are some physical barriers
skin, cilia, hair, urine, and mucous
what are some chemical barriers
saliva, tears, strong acid, and acidity in your skin
