science 5 Flashcards
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What is a pathogen?
organisms that cause disease
There are four types of pathogens: bacteria,
virus, fungi, protists. Pathogens spread by:
1] an infected person
2] soil, food, water
3] a contaminated object
4] an infected animal
what are infectious disease.
a disease caused by a
foreign microorganism within the body.
what is skin?
dead skin cells flake off removing
pathogens from body; outer epidermis acts as
a barrier too; rapid scabbing prevents
pathogen entry into body.
what is the breathing passage?
Nose, mouth, throat
contains mucus and cilia trapping and
removing pathogens. Coughing/sneezing also
removes pathogens.
what is the mouth and stomach?
saliva and stomach acid
can kill pathogens.
What are White Blood Cells?
are disease fighting cells.
There are many different types of WBC’s, each
having its own particular function. Phagocyte (WBC)
eat pathogens destroying them.
What is Inflammation?
increased blood flow (enlarges blood
vessels) bringing more WBC’s to affected area (red,
swollen, warmer).
what is a fever?
increasing body temperature fights infection;
pathogens do not grow/reproduce well at higher
temperatures.
What are antigens?
unique surface marker molecules on pathogen.
what are antibodies?
molecular tag that attaches to antigen to recognize
as foreign.
what are Lymphocytes?
WBC’s that can distinguish between different
kinds of pathogens. Two types:
T-cells (Alarm, Attack): specialized cell that recognizes
each kind of pathogen.T-cells multiply, then some attack
pathogen (“killer T-cells”) while others activate B – cells.
B-cells (Antibody “Tag” Factory): specialized cells that
produce specialized antibodies (proteins) that tag the
pathogen for destruction. The antibody binds to the antigen
on the pathogen, marking it for destruction by the
phagocytes.
what is the Nervous System?
receives and responds to
information gotten both inside and outside of the
body; also helps to maintain homeostasis.
what is a stimulus
an environmental signal that an
organism reacts to.
what is a response?
what the body does in reaction to a
stimulus.
What is a neuron?
specialized cell that carries
information; building block of Nervous System.
what is a nerve impulse?
message/information being carried
What is a neuron?
consists of nucleus, axon and
dendrites.
what are dendrites?
carries impulses toward the cell
body.
what are axons?
carries impulses away from the cell
body.
what are nerve fibers?
axons & dendrites
what is a nerve?
bundle of nerve fibers
What are Sensory Neuron?
picks up stimuli and
converts it into an impulse.
what is a Interneuron?
carries impulse from one neuron
to another neuron (within brain or spinal cord).
what are Motor Neuron?
brings impulse to muscle or
gland which then reacts in response.
what are Nerve impulse?
begins in a nerve cell’s dendrite,
travels down axon to axon tip where it crosses
over to the next nerve cell at the synapse.
what is a synapse?
is the gap between the axon tip and the
neighboring dendrite. Chemicals (dopamine,
seritonine) carry the impulse across the synaptic
gap.
Reflex Arc
what is the nervous system?
Stimulus, response, neuron, nerve impulse, dendrites, axon, nerve fiber,
nerve, sensory neuron, interneuron, motor neuron, synapse, reflex arc,
central nervous system, peripheral nervous system, autonomic nervous
system, somatic nervous system, brain, spinal cord, cerebrum, cerebellum,
brain stem, concussion, stroke
