Transcript Human Body Systems - local.brookings.k12.sd.us

Human Body Systems
Justin Grosdidier
Table of Contents
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Digestive System- Slides 3-13
Circulatory System- Slides 14-24
Respiratory System- Slides 25-34
Immune System- Slides 35-44
Excretory System- Slides 45-52
The Digestive System
Function
• Made up of the alimentary canal and several
accessory organs that break down and absorb
food
• When food is taken in, it isn’t in a form the
body can use. The digestive system changes
this food into a form that can be used and
absorbed by the body.
• Involves mixing food with digestive juices that
break down large molecules into smaller ones
Alimentary Organs
• Mouth- The teeth grind food while saliva and the
enzyme salivary amylase begin breaking down carbs
• Esophagus- Muscular tube the takes food from the
mouth to the stomach
• Stomach- Muscular pouch that receives food, mixes it
with different enzymes, digests proteins, and sends
chyme to the small intestine.
• Small intestine- Long tube that is the main site of
digestion and absorption. It is divided into 3 parts:
Duodenum, Jejunum, and Ileum
• Large Intestine- Completes any absorption and
processes waste into feces.
Accessory Organs
• Pancreas- Secretes pancreatic juice, a liquid
with enzymes and sodium bicarbonate that is
able to stop the digestive process of pepsin
• Liver- Secretes bile; regulates blood sugar
levels; metabolizes proteins, carbs, and fats;
stores glycogen; recycles used up red blood
cells
• Gallbladder- Stores bile produced by the liver
Digestion of Large Molecules
• Digestion is a system of continuously breaking
down larger molecules into smaller ones
• Very large food is broken down by teeth and
saliva in the mouth
• Enzymes in the stomach and intestines then
break down food molecules into forms that
can be absorbed by the body
Enzymes
• Enzymes are used in digestion by breaking down
macromolecules into smaller, easier absorbed
molecules
• Different enzymes are used to digest different types of
molecules
• Salivary amylase is found in saliva and digests carbs
• Pepsin is found in the stomach and breaks down
proteins
• Pancreatic juices break down DNA, RNA, Polypeptides,
and fat molecules
• Bile also breaks down fats
Physical vs. Chemical Digestion
• Physical or mechanical digestion is done mainly in
the mouth. The teeth cut and grind food to make
it easier to swallow and increase its surface area.
Salivary glands begin to secrete saliva into the
mouth
• Chemical digestion is the breaking down of
macromolecules of food into smaller molecules
that are ready for absorption. This is done in the
stomach and intestines by enzymes and other
digestive juices
Carb and Protein Digestion
• Carbohydrates are broken down by saliva, pancreatic
juices, and in the lining of the small intestine.
• Starch is converted first to maltose by saliva and
pancreatic juice then to glucose in the lining of the SI
• Proteins are mainly digested in the stomach by Pepsin.
It is then completed in the SI.
• This is very complicated because proteins are very
large molecules that must be broken down into small
amino acids which can be absorbed into the blood
Drawing and Pics
System Disorders
• Acid Reflux- condition in which the stomach
contents leak back into the esophagus. This
can cause heartburn and many other
uncomfortable symptoms
• Appendicitis- Inflammation and infection of
the appendix and if it is left untreated the
appendix can burst causing infection and even
death
Sources
• http://digestive.niddk.nih.gov/ddiseases/pubs
/yrdd/
• AP Book
• http://hepatitis.about.com/od/overview/ig/O
rgans-of-Digestive-System/Digestive-SystemOrgans.htm
• http://www.nutristrategy.com/digestion.htm
• http://www.rush.edu/rumc/page1098987321204.html
Circulatory System
Function
• The circulatory system is the major means of
transportation throughout the body
• It transports Oxygen from the lungs to the cells of the
body and CO2 from the cells to the lungs.
• Moves other substances throughout the body such as
nutrients absorbed by digestion
• Moves hormones throughout the body
• Contains cells to fight disease
• Stabilizes pH and ionic concentrations of the blood
• Helps regulate body temperature
Blood Vessels
• Blood vessels contain a central lumen lined with an endothelium
with a smooth surface to reduce resistance to blood flow
• The tissue surrounding differs between the different vessels
depending on the function
• Capillaries are very tiny with thin walls. This organization facilitates
gas exchange.
• Arteries and veins have a more complex structure. They both have
an outer layer of connective elastic fibers and a middle layer of
smooth muscle. Arteries have a much thicker wall than that of
veins.
• Arteries are used to transport blood from the heart to the different
body parts and veins take the blood back to the heart.
• Capillaries located between the arteries and veins. They are where
gas exchange takes place.
Route of the blood
• Contraction of right ventricle pumps blood to the lungs via the
pulmonary arteries
• It then receives oxygen from the lungs and returns via the
pulmonary veins to the left atrium
• It then flows into the left ventricle where the oxygen-rich blood is
pumped out through the aorta to the body tissue
• Blood the moves from the aorta to the branches of arteries which
branch into arterioles and then to the capillaries where gas
exchange takes place
• The capillaries rejoin forming venules which take blood to the veins.
• Oxygen-poor blood enters the heart via the vena cava veins which
take blood to the right atrium and then to the right ventricle where
it is pumped back to the lungs
Blood
• Blood is a liquid connective tissue
• The cells of the blood are suspended in a watery matrix
called plasma which makes up over half the blood’s volume
• There are several components of blood including
erythrocytes, leukocytes, and platelets
• Erythrocytes- Red blood cells are the most numerous of the
blood cells. Their main function is to transport oxygen and
carbon dioxide
• Leukocytes- White blood cells are present to fight infection
and other invaders of the body
• Platelets- these are fragments of bone marrow cells that
are responsible for blood clotting
Erythrocytes
• Red blood cells have the responsibility of transporting
oxygen to the different parts of the body
• They are very numerous in the blood
• Everything about their structure is to increase the
efficiency of gas transport
• They are small disks that are biconcave to increase
surface area and increase the rate of diffusion
• They do not have nuclei to leave more space for
hemoglobin
• Each erythrocyte contains about 250 million molecules
of hemoglobin so they can transport about 1 billion O2
molecules
Open vs. Closed Systems
• These are the two main types of circulation of animals with many
cell layers
• In open circulation, circulatory fluid, hemolymph, bathes the organs
directly
• Contraction of the heart pumps hemolymph through vessels into
connected sinuses where exchange occurs. Relaxation of the heart
then draws hemolymph
• In a closed system, blood is confined to vessels and is separated
from the interstitial fluid. The heart pumps blood into large vessels
that branch out into smaller ones that move through the organs.
• Open systems are used by arthropods and many mollusks while
closed systems are found in annelids, cephalopods, and all
vertebrates
Circulation in Different Animals
• Fish- use single circulation where the heart has an atrium and a
ventricle and the blood passes through the heart once in each
circuit
• Amphibians- three-chambered heart: two atria and one ventricle. A
ridge in the ventricle diverts most of the oxygen-poor blood into the
pulmocutaneous circuit and most of the oxygen-rich blood into the
systemic circuit. This changes when underwater.
• Reptiles- three-chambered heart with septum partially dividing the
ventricle. In crocodilians it is complete but the circuits are
connected where the arteries exit the heart.
• Mammals- four-chambered heart in which the left side receives and
pumps oxygen-rich blood and the right receives and pumps oxygenpoor blood
Disorders
• Arrhythmia- This is an abnormal beating of the
heart. Usually this means the heart beats
abnormally faster or slower. This is usually
congenital and caused by a heart defect.
Medication, surgery, and pacemakers are the
normal treatment for arrhythmias
• Hypertension- This is also known as high blood
pressure. Hypertension is very common. It
increases the risk of heart attack and other heart
diseases.
Drawings
Sources
• AP Book
• http://faculty.clintoncc.suny.edu/faculty/mich
ael.gregory/files/bio%20102/bio%20102%20le
ctures/circulatory%20system/circulat.htm
• http://users.rcn.com/jkimball.ma.ultranet/Bio
logyPages/B/Blood.html
Respiratory System
Function
• The Respiratory system is a group of organs
and tissues that allows us to breathe
• This is the system that is responsible for
bringing oxygen into the body and removing
waste carbon dioxide
• The main parts are the airways, lungs, and
connected blood vessels
Alveoli
• The alveoli are small air sacs that are clustered at
the tips of the smallest bronchioles within the
lungs.
• This is the portion of the lung where the gas
exchange occurs
• The human lung contains millions of alveoli,
which together have a surface area of about 100
m2, fifty times the area of the skin
• Oxygen diffuses across the epithelium and into a
web of capillaries while carbon dioxide diffuses
from the capillaries into the air space
Alveoli
CO2 and O2 Transport
• Oxygen is taken in via the air we breathe
• It travels in through the trachea, to the bronchi, bronchioles, and
finally to the alveoli
• It is then diffused into the blood through capillaries which go back to
the heart
• Erythrocytes in the blood attach to and carry up to a billion oxygen
molecules per cell
• From the heart, oxygen-rich blood is pumped to the various parts of
the body
• When the blood reaches it’s destination, it swaps oxygen with carbon
dioxide which is taken back to the heart
• From the heart this oxygen-poor blood is pumped to the lungs where
the CO2 diffuses into the alveoli and leaves the body when we exhale
Oxygen Path
Inhalation vs. Exhalation
• Mammals use what is called Negative Pressure
Breathing which pulls instead of pushes air into
the lungs
• This is possible because of the diaphragm
• When the diaphragm contracts and moves down
it creates a negative pressure area and pulls air
into the lungs (Inhalation)
• Then as the diaphragm relaxes, the pressure
becomes greater inside the body so the air exits
the lungs and out the airway (Exhalation)
Disorders
• Asthma- This is a serious disorder involving the
narrowing of the bronchial airways and restricts
airflow into and out of the lungs. This causes
coughing, wheezing, and difficulty in breathing
• Pneumonia- This is inflammation of the lungs
usually caused by bacteria. The alveoli will
become filled with fluid and inflammatory cells
making the lung solid and restricting space to
take in air.
Drawings
Sources
• AP Book
• http://www.nhlbi.nih.gov/health/dci/Diseases
/hlw/hlw_respsys.html
• http://www.ivyrose.co.uk/HumanBody/Respiratory/Respirato
ry_Conditions.php
Immune System
Function
• The immune system is the defense mechanism
of the body.
• It enables an animal to avoid or limit harmful
infections by either preventing or removing
harmful invaders from the body
• It works to recognize and identify pathogens
that may be invading the body
Major Organs
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•
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Skin-outer protection
Bone marrow- produces blood cells
Thymus- produces mature T cells
Spleen- filters the blood
Lymph nodes- filter the fluid, lymph
Antigens and Antibodies
• Any foreign substance that is recognized by lymphocytes
and triggers a response is called an antigen
• Usually polysaccharides or proteins
• Are either secreted into the extracellular fluid or protrude
from the surface of pathogens or other foreign cells
• These are what the white-blood cells recognize and what
triggers the immune response.
• When the body fights of a certain pathogen the B cells will
sometimes produce plasma cells that secrete a soluble
form of the antigen receptor
• These are called antibodies and the help the body to be
more efficient in recognizing and reacting to familiar
pathogens
Innate vs. Acquired Immunity
• The innate immune response is the first line of defense
• It consists of the exterior barriers (skin), TLR,
Antimicrobial peptides and proteins, inflammatory
responses, and natural killer cells
• Acquired immunity is slower to develop
• This is the recognition of familiar pathogens by the B
and T cells
• They recognize antigens produced by pathogens
• They also produce antibodies which help the
recognition process
Humoral vs. Cell-Mediated
• Humoral immunity is an immune response as a
result of antibodies secreted by B Lymphocytes
• Antibodies bond to intruding antigens and mark
them for destruction and removal
• Cell-Mediated immunity is the immune response
that involves macrophages, natural-killers, T
Lymphocytes, and several cytokines
• This is the opposite of humoral immunity as it
doesn’t involve any use of antibodies
B and T Lymphocytes
• Both B and T cells start out in the bone marrow but T
cells then migrate to the thymus where they mature
while B cells mature in the bone marrow
• “T” for Thymus/ “B” for Bone Marrow
• These are the cells required for acquired immunity as
they recognize and inactivate foreign cells and
molecules
• These cells have antigen receptors that they use to
recognize antigens given off by pathogens invading the
body
• B cells can produce antibodies that help recognize
antigens
Antibiotics and Bacteria
• Antibiotic- “Against living things”
• Sometimes our immune system needs a little
help in the battle against bacteria
• If you are diagnosed with a bacterial infection
you will usually be given some antibiotics
• Antibiotics are mainly used for killing or
preventing the growth of bacteria
• They are very useful but are ineffective against
viral or fungal infections, however
Disorders
• Sometimes, the immune system will turn against particular
molecules of the body itself causing an autoimmune disease.
• There are many forms of autoimmune diseases. One disease,
Lupus, causes the body to create antibodies against histones and
DNA released by breakdown of body cells.
• This causes skin rashes, fever, arthritis, and kidney dysfunction.
• HIV, the pathogen that causes AIDS, both escapes and attacks the
acquired immune response.
• HIV infects helper T cells and mutates at a high rate making it
impossible to get rid of
• Over time, HIV infection destroys the immune system by causing
the loss of T cells
• HIV is incurable, but some treatments can work to slow HIV
reproduction and progression to AIDS
Sources
• AP Textbook
• http://www.thebody.com/content/art1788.ht
ml
• http://en.wikipedia.org/wiki/Cellmediated_immunity
• http://www.bacteriamuseum.org/cms/HowWe-Fight-Bacteria/antibiotics.html
The Excretory System
Function
• The excretory system has the duty of
emptying the body of nitrogenous and other
wastes
• It also regulates water and ion levels in body
fluids
Nitrogenous wastes
• Ammonia can only be tolerated at low concentrations so animals
need access to lots of water
• Most common in aquatic species
• Mammals, most amphibians, sharks, and some bony fishes and
turtles excrete urea
• This is the product produced in the liver that combines ammonia
with carbon dioxide
• Very low toxicity but has a high energy cost
• Insects, land snails, many reptiles, and birds excrete Uric Acid
• This is relatively nontoxic and doesn’t readily dissolve in water
• Can be secreted as a semisolid paste with little water loss
Excretory Processes
• Filtration: Excretory tubule collects a filtrate from the
blood. Water and solutes are forced by blood pressure
across the membranes of a cluster of capillaries
• Reabsorption: The transport epithelium reclaims
valuable substances from the filtrate and returns them
to the body fluids.
• Secretion: Other substances, such as toxins and excess
ions, are extracted from body fluids and added to the
contents of the excretory tubule.
• Excretion: The altered filtrate (urine) leaves the system
and the body.
Disorders
• Gout is a disorder where a human accumulates more
than the usual amount of uric acid
• Since it’s not water-soluble the acid is stored in the
body, usually in the joints, causing pain and
deformation of the joints
• Kidney stones affect millions of people around the
world
• They can be a variety of sizes from microscopic to
filling the entire renal pelvis
• As the stone passes down the ureter the person
experiences much pain and the kidney may be
ineffective for a period of time
Drawings
Drawing
Sources
• AP Textbook
• http://faculty.clintoncc.suny.edu/faculty/mich
ael.gregory/files/bio%20102/bio%20102%20le
ctures/excretory%20system/excretor.htm
• http://biology.clc.uc.edu/courses/bio105/kidn
ey.htm