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
what is teh immune system?
Infectious disease, pathogen, toxin, antibody, antigen, phagocyte,
lymphocyte, T Cells, B cells, immune response, fever, inflammatory
response
what is the endocrine system?
Hormones, Hypothalamus, pituitary, thyroid,
parathyroid, thymus, adrenal gland, adrenaline,
negative feedback loop, gigantism, dwarfism
The endocrine system?
produces hormones
which controls/regulates organ & tissue
activities; regulates growth & development.
what is hypothalamus?
(middle brain): linked to
Nervous System; maintains Homeostasis &
control of pituitary gland.
What is the Pituitary Gland?
growth, blood pressure,
water balance regulates; signals thyroid
gland to produce hormones.
what is the thyroid gland?
produces hormones;
controls energy inside cell
what is Parathyroid?
regulates blood calcium.
what is Thymus?
helps immune system
development
what is pan crease?
controls blood sugar
what is adrenal.
triggers
adrenaline during emergency situations;
“fight or flight response”.
what are ovaries?
triggers egg development
(estrogen); female sexual development
(progesterone).
what are testes?
regulates sperm development;
male sexual development (testosterone)
what is the male reproductive?
produces
sperm and hormone testosterone; consists
of testes, scrotum, penis.
what are testes?
organ that produces sperm and
testosterone (which controls male physical
characteristics).
what is the scoutum?
external pouch containing testes.
What is the semen?
mixture of sperm cells and fluids.
what is a penis?
male sex organ; contains end of
urethra where urine/semen leave the body.
What is the female reproductive system
produces eggs and
hormones estrogen, progesterone; consists of the
ovaries, fallopian tubes, uterus, vagina.
what are ovaries?
produce egg cells and estrogen (which
controls some female characteristics) and
progesterone.
what is the fallopian tube?
connects ovary (egg) to uterus;
where fertilization occurs. Each month, one of the
ovaries releases an egg.
what is the uterus?
hollow muscular organ; the zygote
develops (embryo,fetus,newborn) in the uterus
what is the vigina?
opening between uterus and outside body.
What is in the reproduction system?
Sexual Reproduction (= Meiosis). The gametes
are:
Egg: female sex cell (= 23 chromosomes)
Sperm: male sex cell (= 23 chromosomes)
Fertilization: joining of sperm and egg
Zygote: fertilized egg (= 46 chromosomes)
Note: zygote undergoes cell division (= Mitosis):
zygote → embryo → fetus → newborn (birth).
Chromosome: X-shaped structure in cell’s
nucleus contains units called genes which carries
genetic information (inherited traits).
what is the Mestrual cycle?
monthly cycle of change consisting
of egg development in ovary and uterus prepares
for arrival of embryo.
What is the beggining?
development of mature egg; uterus
thickens
what is the midway?
egg released from ovary into fallopian
tube (= ovulation); where fertilization occurs. If no
fertilization, menstruation (“period”) occurs.
what is menstrual?
blood, unfertilized egg, uterus’s
tissue lining leaves body through vagina.
what is the human life cycle?
amniotic sac, placenta, umbilical cord, birth, delivery,
afterbirth, identical twins, fraternal twins, infancy,
childhood, adolescence, puberty, aging
what is fertilization?
joining of sperm and egg forming
zygote.
what are zygotes?
fertilized egg
what are embryos?
from “two cell stage” to 8 weeks;
what is the fetus?
3-9 months (birth)
what is the amniotic sac?
fluid filled sac that cushions/protects
embryo/fetus
what is the placents?
regulating organ between baby & mother;
nutrients/oxygen in & waste out
what is birth?
Birth: ~ 9 month in humans; three stages:
labor, delivery, afterbirth
Labor: strong muscular contractions of uterus,
cervix (opening) enlarges
Delivery: from uterus to outside world
Afterbirth: contractions push placenta and
other membranes/fluid out through the vagina.
what are identical twins?
from a single fertilized egg
that splits results in two genetically
identical individuals (copies).
what are fraternal twins?
two different
eggs released & fertilized by
two different sperm; two different
individuals sharing the same womb.
what is infancy?
dramatic change in shape & size;
nervous / muscular system development; learning
new physical skills.
what is childhood?
(2-12 yrs): more active, independent,
further physical & mental changes
what is adolesences?
(13-19): gradual change from child to
adult
what is puberty?
(9-15yrs): At 12-14 yrs, ability to reproduce;
produce baby?
what is aging?
(30+ yrs) skin begins to wrinkle, decrease
muscle strength, changing hair color, eye
problems (40-65 yrs) menopause (ovulation,
menstruation stops), decrease sperm
Slow Aging: diet, exercise
