Transcript Immune System- Fights Pathogens

Immune System- Fights
Pathogens
1.
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Barriers that keep pathogens out
Skin
Breathing Passages
Mouth and Stomach
2.
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Inflammatory Response
White Blood Cell
Inflammation
Fever
3. Immune Response
• T Lymphocyte
(T cell)
• B Lymphocyte
(B cell)
The Nervous System
• Receives information
• Directs your body to respond to the
information.
• Helps maintain homeostasis.
General Information about the
Nervous System.
• The Neuron- Cell that makes up Nerves.
• Nerves- Carry information.
• Nerve Impulse- Message ( electrical
signal) carried by the neuron.
• Synapse- Junction (gap) between
neurons.
• 3 types of neurons: sensory, interneuron
and motor.
Nervous System
• Central- control
center of the body.
• Includes Brain and
Spinal cord
• Peripheral- Nerves
that branch out from
the central nervous
system to the rest of
the body.
• It is involved in
voluntary and
involuntary actions.
Endocrine System-Functions
• Produces chemicals called hormones that
control many of the body’s activities.
• Regulates long term changes such as
growth and development.
Hormones
• Chemical product of endocrine gland, that
regulates activities in tissues and organs.
• Travels in the bloodstream until it reaches
its specific organ. These organs have
target cells that are recognized by
hormones.
Endocrine Glands
• Produce and release hormones into the
bloodstream.
• They control activities such as growth,
blood pressure, levels of glucose, etc.
Negative Feedback
When the amount of a certain hormone in
the blood reaches a certain level, the
endocrine system sends a signal to stop
the release of that hormone.
Reproduction in Organisms
Sexual
ReproductionInvolves two
parents.
Asexual
ReproductionInvolves one
parent.
Reproduction in Organisms
DNA
• Carry Hereditary
information.
• Looks like a twisted
ladder called a double
helix.
Gene- Section of the DNA responsible for a trait.
Chromosome- A rod Shape structure, located in the
nucleus that carries DNA.
Chromosome Theory of Inheritance
Traits are passed on from one generation to
the next through chromosomes.
Mutation- Damage in the DNA.
Cancer begins when mutations affect
the normal cell cycle, causing cells to
divide in an uncontrolled way.
Mitosis
• A cell divides to produce two
cells.
• Each daughter cell gets an
identical copy of the DNA.
• Mitosis is used for growth and
repair in multi-cellular organism.
• Mitosis is used for reproduction
in unicellular organisms like
bacteria and multicellular
organisms like a potato plant.
Meiosis
Cells divide to
produce four sex
cells. Each sex
cell has half of the
DNA of the parent.
Male and Female Reproductive
System
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Involves the production of sex cells or gametes.
Egg- Female sex cells
Sperm- Male sex cells
Fertilization- when the egg and the sperm join
together.
• Zygote- Fertilized egg.
• Human body cells have 46 chromosomes.
• Human sex cells have 23 chromosomes.
Male Reproductive System
• Produces sperm
and testosterone.
• Includes testis,
scrotum and
penis.
Female Reproductive System
• Produces eggs.
• Nourishes the developing babies until
birth.
• The organs of the female reproductive
system are the ovaries, the uterus, the
fallopian tubes, and the vagina.
Menstrual Cycle
1. An egg develops in the ovary.
2. The uterus prepares for the embryo and
tissue builds up in the uterine wall.
3. If the egg is fertilized it attaches to the
uterus where it develops until birth.
4. If it is not, the extra tissue and blood
pass out of the body in a process called
menstruation.