Transcript Chapter 40: Immune System Chapter 41: Nervous System Chapter

Immune System
Nervous System
Hormones and Endocrine
Systems
Chapter 40: Immune System
– a disease causing agent
 1st line of defense: Skin and
mucous membranes
 2nd line of defense: inflammatory
response, temperature response,
proteins and white blood cells (wbc)
 Pathogen
 Temperature
response: body
temperature increases to kill bacteria
 Temperature greater than 103oF are
dangerous
 Temperature greater than 105oF are
fatal
– wbc that ingest and
kill pathogens they encounter
 Cytotoxic T Cells – attack and kill
infected cells
 B Cells – labels invaders for later
destruction
 Macrophage
T cells – active cytotoxic T
cells and B cells
 Antigen-substance that triggers an
immune response
 Koch’s Postulates are a guide for
identifying specific pathogens
 Helper
– resistance to a
particular disease
 Vaccine – solution that contains
dead or modified pathogen that can
no longer cause disease. A vaccine
triggers an immune response
without symptoms of infection.
 Immunity
You can get infectious disease
through:
Person
to person contact
Air
Food
Water
Animal
bites
Allergy-the body’s inappropriate
response to a normally harmless antigen
 Autoimmune disease-body launches an
immune response against its own cells
attacking them as they were pathogens.
They can no longer distinguish “self”
from “nonself”.

HIV causes AIDS when the body can no
longer fight off other infections because of
the destruction of helper T cells.
 If a person’s blood contains antibodies to
HIV they are HIV positive.
 HIV is transmitted through body fluids
including blood. Can also be transmitted
through sexual contact, breast milk, and
needles.

Chapter 41: Nervous System
– nerve cell
Neurons enable
movement, perception,
thought, emotion and
learning.
Neuron
Dendrites receive information
FROM other cells.
Axon conduct (sends) nerve impulses
TO other cells
Nerves
are
bundles
of
axons.
Synapse – a junction at which a
neuron meets another cell.
Central Nervous System (CNS)


The CNS consists of
the brain and spinal
cord.
The CNS interprets
and responds to
information from the
environment and from
within the body.
Peripheral Nervous System (PNS)
 Sensory
neurons send information
from sense organs.
 Example of a sense organ: skin,
eyes, ears, nose, mouth
 Motor neurons send commands
from the CNS to muscles and
other organs.
Brain
 Body’s
processing center.
 Contains about 100 billion neurons.
 Enables you to have thoughts,
feelings, emotions, behavior,
memories, and the ability to learn
and process information.
Spinal Cord
 Dense
cable of nervous tissue
that runs through the vertebral
column to a level just below
the ribs.
 Links brain to the peripheral
nervous system.
Somatic Nervous System
Consists of most motor neurons that
stimulate skeletal muscle.
 Reflexes, although involuntary, are also
part of the somatic nervous system. A
reflex is a self-protective motor response.
 Reflex – sudden, involuntary contraction
of muscles in response to a stimulus

Autonomic Nervous System


Consists of peripheral motor neurons that
regulate smooth muscles such as heart rate, all
the body systems, and secretions of glands.
Has 2 divisions:
 Sympathetic – fight or flight response
 Parasympathetic – keeps body functioning
when you are not active (able to breathe
while sleeping)
Chapter 42: Hormones and the
Endocrine System
Hormones
are substances
secreted by cells that act
to regulate the activity of
other cells in the body.
Function:
Regulating growth, development, behavior,
and reproduction
 Coordinating the production, use, and
storage of energy
 Maintaining homeostasis (temperature,
regulation, metabolism, excretion and water
and salt balance)
 Responding to stimuli from outside the body

 Endocrine
glands are ductless organs
that secrete hormones directly into
either the bloodstream or the fluid
around cells. (extra cellular fluid)
 Organs include the brain, stomach,
small intestine, kidneys, liver and
heart.
 Exocrine
glands deliver
substances through ducts
(tubelike structures).
 Organs include sweat glands,
mucous glands, and other
digestive glands.



Target cell are a specific cell that a hormone
binds to and acts on (carriers the message to)
If high levels of hormones stimulate the output
of even more hormone, the regulation is celled
positive feedback.
Negative feedback is a change in one direction
stimulates the control mechanism to counteract
further in change in the same direction.

Hypothalamus is the area of the brain that
coordinates the activities of the nervous
and endocrine systems.
 Controls many body functions including:
 Body Temperature
 Blood Pressure
 Emotions
Pituitary Gland is an endocrine gland suspended
from the hypothalamus by a short stalk.
 Insulin
is a hormone that lowers
blood glucose levels by promoting
the accumulation of glycogen in the
liver.
 Glucagon had the opposite effect of
insulin; it raises blood glucose
levels

Diabetes mellitus is a serious disorder in
which cells unable to obtain glucose from the
blood, resulting in high blood glucose levels.
 Type I – is a hereditary autoimmune
disease (usually treated with insulin dose
everyday)
 Type II – develops in people over 40 due
to obesity and an inactive lifestyle