Mr. T's Science Scene

Inside the Living Body, Part 1

Inside the Living Body can be found (as parts) on YouTube.  Simply search for National Geographics Inside the Living Body.

The movie follows a single human girl from her birth, into infancy, toddlerhood, and elementary school.  Then she moves into the teens, adulthood, and finaly old age.  The movie is about the changes that the body systems go through and it is these changes that the student should focus on.

Here are a summary of notes for the notes packet that goes with the movie (if you couldn't write and watch or if the movie went quicker than you could write down notes):

2.  The respiratory system starts up.  While in the womb the lungs are unused.  The oxygen that the baby uses for cellular respiration comes from the mother and the oxygen in HER blood- which, of course, exchanges nutrients, waste, oxygen with the baby through the placenta.  Once the baby is born, adrenaline "shocks" the lungs into spasming and they continue to breath until the day the person dies.

3.  In order for the baby to keep warm they are insultated with brown fat.  This type of fat has heat producing cells and helps to keep the baby warm after childbirth.  This brown fat, eventually, melts away.  By the way, this is the same fat that hibernating animals use to survive the long cold months providing both food and warmth. . . . . READ MORE

Inside the Living Body, Part 2 and 3

Inside the Living Body can be found (as parts) on YouTube.  Simply search for National Geographics Inside the Living Body.

The movie follows a single human girl from her birth, into infancy, toddlerhood, and elementary school.  Then she moves into the teens, adulthood, and finaly old age.  The movie is about the changes that the body systems go through and it is these changes that the student should focus on.

Here are a summary of notes for the notes packet that goes with the movie (if you couldn't write and watch or if the movie went quicker than you could write down notes):

11.  The major hormone for females is estrogen.  Estrogen is responsible for the development of breasts and reproductive organs/cells.  During puberty, an egg will be released from one of the ovaries and float into the fallopian tubes.  If it is fertilized by a sperm an pregnancy may develop.  If the egg is not fertilized then the female's body will get rid of the unused egg and lining of the uterus during menstration.

In males the major hormone is testosterone.  Testosterone is responsible for a deeper voice, increased muscle mass, a larger heart, and the maturity of sperm cells.

In both males and females the hormone Kisspeptin is secreted from the hypothalamus to signal the reproductive organs maturity and puberty.

12.  Hair is modified dead skin cells that pile up on one another and grows from a hair folicle.

13.  Muscles change over time when we use them.  We actually tear the thin muscle fibers apart when we work out or use our muscles and they grow back double. . . . . . READ MORE

Body System- Basic Information (Part 1) . . . . . . READ MORE

Body System- Basic Information (Part 2) . . . . . . READ MORE

Skeletal / Muscular Systems  (Skeletal Concept Movie)

The skeletal and muscular systems are intimately connected.  Without your skeletal muscles you body (your skeleton) would be unable to move.  The skeleton consists of roughtly 206 bones that serve to give you a shape/structure and protect your soft internal organs.  Another role of the bones is to produce red blood cells which are important in moving oxygen from your lungs to ALL the cells of your body.  Some of the more well known bones are the ribs, skull, spine, pelvis, femur (largest bone in the upper leg), and the jaw (or mandible).  

The skeleton is like a suit of armour and, like a suit of armour, needs joints to bend.  Without joints, you skeleton would simply be a rigid cage that would be unable to move.  There are a number of difference joints.  They are as follows:

A.  Ball and Socket joints.  These joints are found in your shoulders and hips.  They allows the bones to twist and move in a circular or sphereical motion.

B.  Hinge joints:  These are found in your fingers, knees, wrists (sort of), and elbows.  A hinge joint allows movement in one direction and bends the joint- usually forwards and backwards.

C.  Slip joints:  Slip joints are in your spine and allows you to bend and move from side to side.  They are vey flexible.

D.  Fixed joints:  Any part of your body where there was a joint that fused together is a fixed joint.  The do not move.  Fixed joints are found in your skull and your pelvis.

E.  Saddle joint:  A saddle joint is very special and is only found in your thumb.  This joinst lets your thumb move from side to side as well as up and down.  It is a really important joint for holding things and probably contributed greatly to our evolution.

Lastly, your skeleton is held together with LIGAMENTS.  Ligaments are found at all moving joints and hold the bones that make up the joint together.  You have ligaments all over your body but your shoulder, elbow, and knees are common areas where ligaments hold your skeleton together.

The muscular system consists of three types of muscles: . . . . READ MORE

Nervous Systems

In order to survive as an organism you MUST do two things: receive information and process that information.  Both of these very important jobs are done by your nervous system!  The nervous system has two parts to it; they are:

A.  The Central Nervous System (CNS)

This system is easy to remember because the whole thing is in the center of your body and consists of the brain and the spinal cord.  It is extremely important because it contatins your brain which influences EVERYTHING your body does, it learns and holds memories, and has cells that will not renew themselves.  The spinal cord runs down the center of your spine and is responsible for moving electrical impulses up AND down at the same time- bringing new "information" up to the brain and sending down "action impulses" to the body.

B.  The Peripheral Nervous System (PNS)

Peripheral means "to the sides" and that is where this part of the nervous system goes- to the sides of your body; out from the spinal cord.  Sensory nerves are nerves that are attached to your senses and bring new "information impulses" up to your brain for processing.  Motor neurons are nerves that carry "action impulses" to your body- primarily to your skeletal muscles to make you move. . . . . READ MORE

Digestive System

One of the more familiar systems is the digestive system.  We use this system to break down the food we eat into usable nutrients for our body's cells.  It also gets rid of solid waste.  This system consists of the following:

Mouth:  Place of mechanical (teeth/chewing) and chemical digestion (saliva).  It is the beginning of the "food tube"

Esophagus:  Muscles in the esophagus push the food down to the stomach (peristalsis) with smooth muscle.  Gravity has little to do with it!

Stomach:  A sac which holds and chemically breaks down the food with HCl acid.  Some mechanical digestion but mostly chemical digestion.  It is in the stomach that the food is turned into a nutrient rich substance called Chyme (think grey milkshake).

Small Intestine:  The stomach and small intestine are connected at the duodenum (LE).  This is the fancy name for the beginning of the small intestine.  Here the chyme is sprayed with bile.  Bile is produced in the liver, stored in the gall bladder, and sprayed from the gall bladder through a tube connected to the small intestine.  The bile is your body's "dish soap".  It breaks down large fat blobs into small fat blobs that can be handled by the small intestine's villa.  This is mechanical digestion. . . . . READ MORE


Enzymes are chemicals (mostly proteins) that lower the activation energy needed to perform some chemical reaction.  The activation energy is the energy required to make the chemical reaction happen!  Without enzymes, our bodies would still undergo chemical reactions but they would be so slow that we would not function correctly or in enough time to do us any good.  For example, we would still digest lunch BUT it would take us days instead of hours.  

An enzyme has a specific active site shape that will only receive certain chemicals- called reactants or substrate(s).  These substrates usually come in two forms- seperate and need to be bonded together or whole and need to be broken apart. . . . . READ MORE

Respiratory System

The respiratory system consists of the following parts:

A.  Nose and Mouth

B.  Trachea: open tube down to your lungs

C.  Bronchi:  Place where the trachea "splits" in two and branches into the left and right lungs

D.  Bronchioles:  The bronchi become a network of fine tubes that spread all over the inside of the lungs.

E.  Alveolies:  At the end of the bronchioles are millions of tiny, grape clustered sacs where oxygen and carbon dioxide is exchanged.

F.  Lungs:  The lungs are simply large organs designed to hold all the bronchiole tubes, alveoli, and veins and arteries that are coming from and going to the heart.

G.  Diaphram:  The sheet-like muscle that seals the chest cavity and, when flexed, allows air to be forced into the body (see below).

Breathing is done be only a few organisms on the planet; mammals, birds, and reptiles. . . . . READ MORE

Circulatory System

In order for oxygen to get to the cells, for carbon dioxide to be carried away from the cells, for sugar to get to the mitochondria you need a circulatory system!  This system consists of the heart, the blood vessels, and the blood.

The heart is a four chambered organ that completely separates the "bad" blood and the "good" blood.  By "bad" blood we mean that the blood is full of carbon dioxide.  By "good" blood we mean blood that is full of oxygen.  When the two kinds of blood DON'T mix we are able to get fully oxygenated blood to our cells for energy production.  We are able to make so much energy, that we have some left over to keep us (internally) warm.  This makes us (mammals, birds, and retiles) warm blooded.

So the heart has four chambers and when you look at it in a picture you need to remember that left and right are SWITCHED!  Knowing that lets begin the flow of blood, follow it around the body, and back to the heart.

1.  The bad blood enters the heart through the right atrium from the Superior and Inferior Vena Cavas.  The blood has come from the body and is full of carbon dioxide.

2.  The bad blood then gets pumped into the right ventricle.  

3.  From the right ventricle the heart pumps the carbon dioxide filled blood through the pulmonary artery and to the lungs.

In the lungs the carbon dioxide diffuses into the alveoli and is exhaled.  At the same time the oxygen diffuses into the blood. . . . . READ MORE

Endocrine System

The endocrine system is a system of glands which secrete hormones to control the body and react to outside stimuli.  This system is very much like the nervous system with a few differences:

Endocrine System:  Uses glands and hormones

Nervous System:  Uses nerves and electrical impulses

Endocrine System:  In general, works slowly (especially when compared to the nervous system)

Nervous System:  Works very fast- almost immediately!

Endocrine System:  Affects a much more general and wholistic portion of the body.

Nervous System:  Affects a very specific portion of the body- mostly the skeletal muscles. . . . . READ MORE

Excretory System

The excretory system is a weird system that is composed of other systems that already to the "job" of the excretory system.  The excretory system is responsible for getting rid of non-solid waste.  Non-solid waste is water, carbon dioxide, heat (?), etc.  There are ALREADYsystems that do this.  They are:

Respiratory system (gets rid of carbon dioxide)

Urinary system [bladder, kidneys, ureters, urethra] (gets ride of water)

Integumentary system [skin and hair] (gets rid of heat and water)

So technically, the organs of the excretory system are the skin, lungs, bladder, kidneys, ureters, urethra- but these are all organs of "regular" systems already.

Ultimately you need to know that the excretory system (by way of other, established systems) gets rid of non-solid waste.  The digestive system gets rid of solid waste (pooh!). . . not Winnie the! . . . . READ MORE

Reproductive System (Reproductive Concept Movie)

Reproduction of organisms falls under two different and distinct processes:

1.  Sexual reproduction.  This form of reproduction uses sperm and egg cells and a process of fertilization where the DNA of the sperm merges with the DNA of the egg.  It requires a male and female.  Sexual reproduction may be internal (mammals, birds, repiles) or external (amphibians, fish, plants).  The pros of sexual reproduction are the mixing of the DNA which causes variation.  Variation is a prime factor in a species continued evolution and existance in a changing environment.  The cons of sexual reproduction is that it takes a lot longer to produce offsping- relatively.

2.  Asexual reproduction.  Asexual reproduction is mitosis, "cloning", or "copying".  This form of reproduction DOES NOT use egg or sperm cells.  There is one "parent" cell which copies its DNA and splits- mitosis.  The pros to asexual reproduciton is speed!  News cells are formed at a rapid and exponential rate.  The cons of asexual reproduction is that all the "offspring" are the same as the "parent".  This is bad because if a factor is able to kill one cell it can, theoretically, kill all of them.

The male reproductive system exists to make and deliver sperm cells to the female reproductive system.  A male can make sperm cells their entire life.  It consists of the following parts: . . . . READ MORE

Reproductive System- Fertilization (Reproductive Concept Movie)

Fertilization of the egg by the sperm cell is necessary for the production of offspering.  Without it, there will be no offspring and no future species- the species will die out.  

(all numbers are made up but make the point)

During sex the male will release millions of sperm into the female reproductive system- say 10 million sperm.  Immediately, the chemicals of the vagina will kill off most of the sperm.

Those that survive will swim through the cervix and into the uterus- say 1000 sperm cells.

At the top of the uterus the sperm cells will either go left or right into the fallopain tubes- say 100 sperm cells.

There is no real "rhyme or reason" but some  sperm will go left and some will go right.  Say, 60 go left.  There may or may not be an egg in that fallopian tube.  There isn't (in this example) and those 60 sperm will die.  The other 40 will go right where there is an egg.

Those 40 sperm cells swim to the egg where only 10 make it. . . . . READ MORE