THE NERVOUS SYSTEM #1

The nervous system receives information from inside and outside your body, decodes the information, then directs the way you will respond to it.

The entire system is made of nerve cells called, Neurons. (You need to draw the neuron pictured below)

The neuron above has 3 main parts; the dendrites, that carry messages to the cell body, cell body, which contains the nucleus and organelles of the cell, and the axon, which carries impulses to the dendrites of the next neuron.

Every axon tip ends in a synapse, which is a tiny space between the axon of 1 neuron and the dendrites of the next neuron. A nerve impulse has to jump the synapse to continue moving in the body.

A sensory neuron will pick up a stimulus and send it towards the spinal cord - the spinal cord will carry it to the brain - the brain will decode the message and choose a response. Then the response, the message, travels back in the other direction on a new set of nerve cells from the brain to the spinal cord, to the nerves, finally ending in a motor neuron which sends the message to muscle. (Don’t Draw the Brain)

And all this stuff happens

in milliseconds!!

Impulses can reach speeds

of 380 feet/second or 250 miles/hour

Parts of the Brain#3

The Brain and Spinal Cord make up the Central Nervous System (CNS). Both of those are protected by bone, no other nerves are!

The Brain

Cerebrum – Largest part of the brain. It interprets data from the senses, controls movements, and is the center of learning and memory. The cerebrum also is broken into hemispheres – the left and right, the left controls the right side of the body, and the right controls the left side!

Cerebellum – Balance and coordination of muscles.

Medulla Oblongata (Brainstem) – controls your involuntary activities, like breathing and heartbeat.

Label the brain

Parts of the Nervous System #4

Central Nervous System – made up of the Brain (control center for the body) and Spinal cord (a column of nerve tissue running down the back that links the brain to all other parts of the body)

Peripheral Nervous System – the network of nerves that branch out from the Spinal cord and connect to the rest of the body. The PNS is further divided into the :

Somatic Nervous System – voluntary actions

Autonomic Nervous System – Involuntary actions

Draw Reflex ARC below

Digestive Process #5

  • Two types of digestion
  • Mechanical Digestion – muscle movements grind the food
  • Chemical Digestion – chemical reactions in the body digest the food
  • The first step of digestion is the process when food is broken into materials the body can use, this is called digestion.
  • Next, the materials are absorbed into the blood and carried all over the body, this is called absorption.
  • Finally, unusable materials, wastes, are eliminated from the body.
  • Enzymes are the key to chemical digestion. An enzyme is a protein that speeds up chemical reactions in the body. Saliva in the mouth and digestive acids in the stomach and small intestine contain enzymes.
  • Food will follow this path of digestion
  • Mouth to esophagus, but remember the epiglottis helps. What is the epiglottis?
  • Esophagus to stomach, each is lined with mucus. What is mucus and why does it line the stomach?
  • Stomach to small intestine, the small intestine is where absorption of most nutrients occurs. Why is absorption so important?
  • Small intestine to large intestine, absorption also occurs in the large intestine, but it is a different type of absorption. What do you think is absorbed in the large intestine?

Digestive Organs #6

*Food and its parts are contained in order in the following organs:

Mouth

Esophagus

Stomach

Small Intestine

Large Intestine

Rectum

*Other organs play an important role in digestion, but do not touch the food. They are:

Salivary Glands – produce saliva, which has enzymes to chemically digest food and moisten food to make swallowing easier

The Liver – produces bile, which breaks down fat molecules

The Gallbladder – stores the bile produced in the liver and then sends it to the stomach

The Pancreas – produce many enzymes that help break down fats, proteins, and carbohydrates

Nutrients#7

The substances in food the body needs so it can carry out normal life functions!

6 Major Nutrients

1. Carbohydrates – major source of energy. Broken down in the Small Intestine

2. Fats – highest energy nutrient (2 times greater than carbohydrates). Broken down by bile, made in the liver.

3. Proteins – growth and repair of tissue in your body. Broken down by Pepsin and Hydrocholoric Acid in the Stomach.

4. Vitamins – help with the body’s chemical reactions

A – eyesight and skin

B – Healthy nervous system, red blood cell production

C – healthy bones and teeth

K – blood clotting

5. Minerals – Are used in building cells, sending nerve impulses and carrying oxygen to body cells

Iron

Potassium

Sodium

Calcium

6. Water – most vital, it helps with all the body’s important reactions such as digestion. Your body is over 60% water you must replenish what you use!

EXCRETORY SYSTEM #8

TO EXCRETE MEANS TO ELIMINATE OR REMOVE WASTE FROM BLOOD, ORGANS, OR THE BODY

*THE KIDNEYS ARE THE MAJOR EXCRETORY ORGAN, BUT THE LUNGS, SKIN, RECTUM, ANUS, AND LIVER ARE ALSO IMPORTANT.

*THE KIDNEY USES SMALL UNITS CALLED NEPHRONS TO FILTER THE BLOOD AND PRODUCE URINE.

*THE URINE IS THEN HELD IN THE BLADDER UNTIL RELEASED.

*THE LUNGS RELEASE WASTE GASES (CARBON DIOXIDE).

* THE SKIN PRODUCES AND RELEASES PERSPIRATION (SWEAT).

*THE LIVER CLEANS BLOOD TOXINS THEN PRODUCES UREA WHICH CAN THEN BE FILTERED BY THE KIDNEYS.

Urinary Prat of Excretion #9

Draw the System and Label

Skin #10

- Skin is part of the Excretory and Integumentary System

of the Human Body.

- Skin covers the body;

prevents the loss of water;

protects the body from infection and injury;

helps to regulate body temperature;

gets rid of wastes (sweat);

receives information from the environment; and

produces vitamin D.

- Not only does sweat remove waste material, it cools the body by the process of evaporation. As water sits on the skin it heats and evaporates into water vapor. The process of evaporation cools the body several degrees.

- Ever heard of the Heat Index during summer. It is harder for the sweat to evaporate on Hot, Humid days, making the air temperatures on your body feel hotter than they actually are.

Infectious Disease #11

Infectious Disease – can pass from one organism to another

Important Scientists:

  • Louis Pasteur – showed that microorganisms cause certain kinds of diseases – killing them could prevent the spread of those diseases
  • Joseph Lister – microorganisms cause infections – used carbolic acid to disinfect
  • Robert Koch – each infectious disease is caused by a particular microorganism
  • Alexander Fleming – discovered penicillin (1st antibiotic)
  • Jonas Salk – polio vaccine

Pathogen – materials that cause disease; get inside the body and damage its cells

  • Bacteria – single celled (tetanus, strep throat, food poisoning, etc)
  • Viruses (non-living) – must reproduce inside living cells (polio, measles, small pox, chicken pox, AIDS, rabies, flu, common cold)
  • Fungi
  • Protists

How Diseases Spread

  • Person-to-person: direct contact; air
  • Contaminated Objects: water, food, dirty towels, silverware, etc…
  • Animal Bites: rabies (affects the nervous system); Lyme disease (ticks); malaria (mosquitoes)
  • Naturally in the environment: tetanus; botulism

Pathogens - Bacteria #12

All Bacteria are Prokaryotes – cells have NO nucleus or other membrane bound organelles!

Bacteria Classification

Are first classified by their shape:

Round (spherical) – Cocci

Rod – Bacilli

Spiral – Spirilla

Bacteria Fun Facts

1. Most bacteria are helpful. Some uses are:

Fuel and Food production

Environmental recycling and cleanup as decomposers

Production of Medicines

2. Bacteria reproduce by BINARY FISSION – the process by which one cell divides to form two new cells. Why is the above processes important to bacterial survival?

3. Bacteria can also cause infectious disease. Common bacterial infectious diseases are:

Food Poisioning – Botulism and Salmonella spread by eating undercooked infected foods, causes severe abdominal pain

Tetanus – Tetani bacteria lives in the environment so gets into cuts easily, causes lockjaw

Strep Throat – Streptococcus bacteria causes throat soreness and high fever. Highly contagious!

4. Bacteria can be fought with antibiotics (passive immunity) and vaccinations (active immunity), but the vaccinations usually don’t last for a lifetime.

The Virus #13

CHARACTERISTICS

  • Have DNA
  • Have a protein coat that surrounds the DNA, called a capsid
  • They come in various shapes – some have a flat or spiked envelope around the capsid
  • Shapes include: rod, polyhedral, spiked, and the unusually shaped bacteriophage.

A virus cannot function without a host cell. It must be in the host cell in order to replicate.

Therefore, is a virus living or not?

Some viral diseases in humans:

  • Small pox
  • Polio
  • Measles
  • AIDS (caused by HIV)
  • Mumps
  • Flu
  • Yellow Fever
  • Colds

There is no known cure for a virus. It just has to run its course. You can treat the symptoms, but you can’t kill the virus.

Virus – mean poison in Latin

Non-infectious (Intrinsic) Disease#14

These are diseases you can’t catch from another person or another organism. You simply have them from birth or get them somehow during your life. Some are the result of poor lifestyle choices (like Diet and Exercise), others are the result of our own body cells mutating, and many are just unlucky!

Such common diseases are:

Allergies – your body is overly sensitive to a foreign substance

Asthma – respiratory disorder where air passages narrow making it hard to breathe

Diabetes – failure of the pancreas to produce enough insulin, or your body’s cells can’t use the insulin properly. This results in high glucose levels in the blood, which can damage the kidneys. Also the body’s cells aren’t getting the sugar they need to make energy.

Cancer – cells in the body multiply uncontrollably destroying healthy tissue in the process

Heart disease – nation’s leading disease killer, many types and forms of heart disease but it’s generally associated with heart attacks and artery blockages

Crohn’s disease – digestive tract inflammation of unknown cause

Parkinson’s disease – A degenerative brain disorder caused by damage to the cells of the brain that produce a neurotransmitter called dopamine. Without dopamine nerve impulses can’t travel over synapses. Parkinson’s causes movement problems.

Generally there are no cures with medicine! Sometimes surgery will help or medicines will delay the progression of the disease.