Flash Card #5
What is a pathogens?
organisms that cause disease
What is an infectious disease?
a disease caused by a foreign microorganism within the body.
What are the four types of pathogens?
bacteria,virus, fungi, protists
How are Pathogens spread?
1] an infected person
2] soil, food, water
3] a contaminated object
4] an infected animal
what is the first line of defense against Pathogens?
Barriers That Trap & Kill
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 are breathing passages?
Nose, mouth, throat
contains mucus and cilia trapping and
removing pathogens. Coughing/sneezing also
removes pathogens
What is the the mouth and stomach?
saliva and stomach acid
can kill pathogens
What is the second line of defense against Pathogens?
Inflammatory (General) Response
What are white blood cells?
are disease fighting cells.
There are many different types of WBC’s, each
having its own particular function
What are 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 is the third line of defense against Pathogens?
Immune System’s (Targeted) Response
What are antigens?
unique surface marker molecules on pathogen.
What are antibodys?
molecular tag that attaches to antigen to recognize as foreign
What are lymphocytes?
WBC’s that can distinguish between different
kinds of pathogens
What are 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
What are 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 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 nerve impulse?
message/information being carried
What does a neuron consists of?
consists of nucleus, axon and
dendrites.
What do dendrites carry?
carries impulses toward the cell
body.
What do axons carry?
carries impulses away from the cell
body.
What are nerve fibers?
axons & dendrites
What is a nerve?
bundle of nerve fibers
What is 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 is a motor neuron?
brings impulse to muscle or
gland which then reacts in response.
What is 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.
What is the endocrine system?
produces hormones
which controls/regulates organ & tissue
activities; regulates growth & development.
What is the hypothalamus?
produces hormones
which controls/regulates organ & tissue
activities; regulates growth & development.
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 the parathyroid?
regulates blood calcium.
What is the thymus?
helps immune system
development
What is the pancreas?
controls blood sugar
What is the adrenal?
triggers
adrenaline during emergency situations;
“fight or flight response”.
What are the ovaries?
triggers egg development
(estrogen); female sexual development
(progesterone).
What are the testes?
regulates sperm development;
male sexual development (testosterone)
What is the male reproductive system?
produces
sperm and hormone testosterone; consists
of testes, scrotum, penis.
What is the scrotum?
external pouch containing testes.
What is semen?
mixture of sperm cells and fluids.
What is the 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 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 vagina?
opening between uterus and outside body.
What is and egg?
female sex cell (= 23 chromosomes)
What is sperm?
male sex cell (= 23 chromosomes)
What is fertilization?
joining of sperm and egg
What is the zygote?
fertilized egg (= 46 chromosomes)
Note: zygote undergoes cell division (= Mitosis):
zygote → embryo → fetus → newborn (birth).
What are chromosomes?
X-shaped structure in cell’s
nucleus contains units called genes which carries
genetic information (inherited traits).
What is the menstrual cycle?
monthly cycle of change consisting
of egg development in ovary and uterus prepares
for arrival of embryo.
What is the beginning?
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 menstruation?
blood, unfertilized egg, uterus’s
tissue lining leaves body through vagina.
What is an embryo?
from “two cell stage” to 8 weeks;
cell division occurs.
what is the fetus?
3-9 months (birth)
What is the amniotic sac?
fluid filled sac that cushions/protects
embryo/fetus
What is the placenta?
regulating organ between baby & mother;
nutrients/oxygen in & waste out
What is the umbilical cord?
connects fetus to placenta
(belly button)
What is birth?
9 month in humans; three stages:
labor, delivery, afterbirth
What is labor?
strong muscular contractions of uterus,
cervix (opening) enlarges
What is delivery?
from uterus to outside world
What is 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 ferternal 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?
more active, independent,
further physical & mental changes
What is adolescence?
gradual change from child to
adult
What is puberty?
At 12-14 yrs, ability to reproduce;
produce baby
What is aging?
skin begins to wrinkle, decrease
muscle strength, changing hair color, eye
problems (40-65 yrs) menopause (ovulation,
menstruation stops), decrease sperm
What is slow aging?
diet, exercise