Biology Anatomy and Physiology

Organization Within the Body Cells- Basic unit of life, smallest functional unit within living things –Cell Specialization- different types fo cells complete different tasks within the body Tissues- Group of cells working together to complete a common task (4 types) Organs- A structure made of 4 different types of tissues working together to complete a major task Organ System- A group of organs working together within the body to complete a number of major related tasks within the body

Types of Tissues in the Body Epithelial- covers body, and lines digestive system and major organs of the body Nervous- relays messages within the body Connective-Holds organs in place and binds different parts of the body together Muscle- capable of contraction, causes internal and external movement

Major Body Systems Nervous SystemIntegumentary SystemSkeletal SystemMuscular SystemCirculatory System

Functions of Body Systems Nervous- coordinates the body’s response to changes in internal and external conditions Integumentary- serves as a barrier against infection and injury Skeletal- aids in movement, stores mineral reserves a provides a site for blood cell formation Muscular- voluntary movement, circulates blood, and moves food through digestive tract Circulatory- brings materials to and from cells, fights infection, and regulates body temperature.

Major Body System Respiratory SystemDigestive SystemExcretory System Endocrine SystemReproductive SystemLymphatic System

Functions of Body Systems (cont.) Respiratory- provides oxygen and removes carbon dioxide Digestive- converts food into glucose and other usable molecules for cells Excretory- eliminates wastes and maintains homeostasis Endocrine- controls growth, development, metabolism, and reproduction Reproductive- produces reproductive cells Lymphatic- helps protect the body from disease

Homeostasis Maintaining relatively stable conditions within the body Examples: ~maintaining constant body temperatures ~maintaining “normal” amounts of oxygen and carbon dioxide in the body

Body Systems Work Together to Maintain Homeostasis EXAMPLE Nutrient Delivery and Waste Disposal Digestive System breaks down food and delivers nutrients (glucose) to Circulatory System Oxygen moves from the air into the lungs (Respiratory System) and is delivered to the circulatory system Circulatory System delivers oxygen and glucose to cells Cells complete Cellular Respiration and breakdown glucose and use energy to regenerate ATP Waste products of cellular respiration (CO 2 and H 2 O) are released from cells and taken back to lungs by circulatory system Lungs exhale waste The NERVOUS SYSTEM Coordinates all these interactions! The bodies cells need nutrients to complete tasks and perform chemical reactions, when these nutrients are used wastes are created that must be removed Cells need glucose and oxygen for cellular respiration to make more ATP Carbon dioxide and water are created in this process

Feedback Inhibition (Feedback Loops) The process by which the product of a system shuts down the system or limits its operation Example fat cells grow larger and larger. as the cells grow they release leptin (chemical messenger) leptin signals the brain to suppress the appetite

The Nervous System Basics

Function of the Nervous System Mediates (coordinates) communication between different parts of the body and the body’s interactions with the environment

The Neuron specialized cells within the nervous system Axon terminals Myelin sheath Nodes Cell body Axon Nucleus Dendrites

Neurons transmit messages Nerve impulse = Message Dendrites- pick up message from environment or other neurons. Sends message to cell body Cell body-performs normal cell tasks for cell, relays message to next neuron through the axon Axon- Carries message from the cell body to the next neuron. myelin sheeth-coating that insulates and speeds up message. axon terminal- releases chemicals, “neurotransmitters” to stimulate the next neuron to “fire” or continue the nerve impulse. threshold- the minimal amount of stimulus required to cause the next neuron to “fire” or continue the impulse

Nerve Impulses Are Electrical As They Travel Through The Neuron Outside of cell Inside of cell Cell membrane High Potassium Ion (K+)Concentration Inside Low Potassium Ion (K+)Concentration Outside High Sodium Ion (Na+) Concentration Outside Low Sodium Ion (Na+)Concentration Inside Resting Potential-When a neuron is ready “fire” if it is hit with a “threshold” stimulus 1)Sodium is pumped out by a protein pump *ATP needed 2)Potassium ions leak through cell membrane creating a negative charge inside cell and positive charge outside cell RESTING POTENTIAL NOW REACH WHEN INSIDE HAS BECOME NEGATIVE

At the leading edge of the impulse, the sodium gates open. The membrane becomes more permeable to Na + ions and an action potential occurs. As the action potential passes, potassium gates open, allowing K + ions to flow out. The action potential continues to move along the axon in the direction of the nerve impulse. At rest. Action Potential Movement of the “Action” Potential Action Potential = A electrical charge moving through a neuron CAUSED BY SODIUM GATES OPENING ALLOWING Na+ IN Once Action Potential Passes Na + Gates Close and Na+ Pumped Back Out and Resting Potential Restored

Types of Neurons Sensory Neurons-detect stimulus send a nerve impulse to brain (sensation) Interneurons-located in the brain, process information received and formulate responses (thought) Motor Neurons- carry an “action” or response impulse from the brain back to the body (response)

REFLEX ARC What is the pathway of nerve impulse as your hand touches a hot stove? SENSORY NEURON  INTERNEURON  MOTOR NEURON This is called the a reflex or reflex arc? This process can also occur with conscious control. Can you think of an example of this?

Sense Organs Nose=Smell Mouth=Taste Ears=Sound Eyes=Sight Skin=Touch –All have specialized sensory neurons to pick up or detect stimulus that transmit impulses to the brain for processing

The Central Nervous System Consists of the brain and spinal cord Both the brain and spinal cord is wrapped in 3 layers of connective tissues called the meninges. –dura mater, arachnoid, pia matter Between the meninges and the brain/spinal cord is cerebrospinal fluid –Bathes brain and spinal cord –Shock absorber –Exchange of nutrients and waste between blood and nervous tissue

The Brain

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The Spinal Cord Like a “major telephone line” 31 pairs of spinal nerves branch out from the spinal cord to the rest of the body. –Reflexes may be processed directly by the spinal cord

The Immune System Basics

Pathogens of Disease Bacteria –Bacteria are cellular (prokaryotic) and are Living organisms - 3 common shapes Bacilli (rod), cocci (circular), spirilli (spiral) –Cause disease by Destroying cells and tissue Releasing toxins in body –Examples Strep Throat, tetanus, anthrax, syphilis, tuberculosis, MRSA, food poisoning, chlamidia, gonorhhea –Preventions Some have vaccines, personal hygiene, antiseptics –Treatments Antibiotics- substances that can be administered that kill the bacterial cells causing infection –Usually break down cell walls or interfere with metabolic processes

Pathogens of Disease Viruses –Noncellular particles Genetic material (DNA or RNA) Capsid-protective coating made of protein –Not considered living Cannot reproduce on own, no metabolic processes, no response to stimulus –Cause disease by Disrupting cellular activity and destroying cells –Examples Common Cold, Flu, Small Pox, HIV, chicken pox, genital warts, herpes, hepatitis –Prevention Some have vaccines, personal hygiene, antiseptics –Treatments None- body must defeat on own, some the body cannot defeat EVER Some drugs (antiviral) can slow the spread of virus within the body

Function of the Immune System to fight infections and protect the body from invaders. White Blood Cells-Specialized cells of the immune system fight disease

Pathogens Bacteria (food poisoning, tuberculosis, pneumonia) Viruses (influenza, AIDS, colds,ect..) Protists (malaria and others) Infect body and cause disease! Antigen- a substance on the surface of a pathogen that triggers an immune response (DEFENSE).

Nonspecific Defenses Skin- Creates barrier between external environment where pathogens exist and the inside of the body –Pathogens must enter body to cause infection/sickness Inflammatory Response (Swelling)-Blood vessels expand and WHITE BLOOD CELLS (disease fighters) enter the wound or infection site Fever- Body raises core temp. to try to kill pathogen –Some pathogens can only survive under certain temp.

Specific Defenses Humoral Response –Involve Special Types of White Blood Cells T-Helper Cells activate B-Cells when they detect invaders (pathogens) B- Cells (B lymphocytes) produce plasma cells Plasma cells produce antibodies –antibodies=substance that will cling to the antigen on the surface of a pathogen an immobilize the pathogen or cause them to cling together. –Once infection detected by helper T many plasma cells are generated B cells to produce antibodies Macrophages (PHAGOCYTES)-engulf and destroy immobilized or inactivated pathogens

Specific Defenses Cell Mediated –Helper T Cells- recognize pathogens and activate B cells (Humoral Response) and Cytotoxic (Killer) T Cells –Killer T Cells- Once activated kill pathogen directly

Immunity Bodies ability to not become sick against a specific invader/pathogen –It takes a while for plasma cells to figure out what antibody will kill a specific pathogen, many antibodies are produce in “trial and error method” –Pathogen causes infection and sickness in meantime –Eventually plasma cells produce an antibody that works. –Special B memory cells remember the correct antibody that worked against that specific invader –The next time the invader enters your body the Immune system knows how to destroy it before it can cause infection or disease.

Vaccine Altered (weakened) form of the real pathogen Scientists alter in lab –No longer capable of causing disease –Injected in body –Allows body to recognize and immune system build immunity to the pathogen When the real pathogen enters body your body is already immune (knows how to kill it before it can cause infection/sickness)

Treatments for Diseases Bacterial Diseases- bacteria are living things –Antibiotics-drugs that interfere with the chemical processes of living things Specifically harm bacterial cells without causing harm to us Viral Diseases-not living –Body must defeat on own, no cures

A.I.D.S and the Body AIDS infects and kills Helper T Cells Helper T Cells detect pathogens/invaders Once enough T Helper are killed by virus the body is no longer capable of recognizing invaders RESULT- Person becomes seriously infected or sick from pathogens that a healthy person may defeat rather easily –Usually die from simple infections (cold,flu,pneumonia)

The Digestive System Function- convert foods into simpler substances that can be used by cells.

Digestion Breaking food particles down into simple substances that cells can used by cells Mechanical Moistening and breaking food particles into smaller pieces Chemical Breaking down chemicals within food into simpler substances –Proteins  amino acids –Fats  lipids –Carbs Polysachararides /starches  monosacharrides / sugars (glucose)

Digestive Enzymes Mouth Salivary Amylase- carbs Stomach Pepsin (proteins) Small Intestine (from Pancreas) Amylase- carbs Trypsin- proteins Lipase- fats Small Intestine Maltase, Sucrase, Lactase- carbs Peptidase- proteins

Mouth Mechanical Digestion –Chewing –Moistening (saliva) Chemical Digestion –Salivary Amylase Enzyme breaks down carbs

Esophagus Epiglottis covers trachea (windpipe) and forces food into esophagus Tube that leads from throat to stomach (lined with smooth muscle) –Peristalsis- wavelike muscular contraction that helps “push” food downward.

Stomache Mechanical Digestion- HCl helps “liquefy” foods and churning motion also breaks food into smaller pieces –Food is now chyme Chemical Digestion –Pepsin (breaks down Proteins)

Liver Produces Bile- –Bile is a substance that acts as a detergent and breaks down fat molecules Bile is stored in gall bladder and then released into the small intestine Has over 500 other critical functions –Mainly breaking down toxins And “purifying” blood

Gall Bladder Stores Bile that is made by liver –Releases bile Into small intestine

Pancreas Produces many digestive enzymes –These enzymes are released into the small intestine –Also produces base Alkaline substance That neutralizes stomach Acid in small intestines

Small Intestine Name refers to diameter, is actually much longer than large intestine 6 meters long –Almost 20 feet! 3 Parts –Duodenum-chemical digestion –Jejenum-chemical digestion & nutrient absorbtion –Ileum- nutrient absorbtion

Nutrient Absorption in Small Intestine takes place in jejenum and ileum Chyme is now well digested and rich in nutrients Folded surfaces are covered with fingerlike projections called villi –Villi have are intervened with capillaries from circulatory system –Nutrients are absorbed into bloodstream

Large Intestine (Colon) Water absorption Production of vitamin K –Accomplished by bacterial cells in digestive tract