GRADE: Seventh

CONTENT STANDARD: Life Science

CONTENT TOPIC: Living Systems

CONCEPT: The human body is composed of different biological systems that are interrelated and dependent upon one another.

CONTENT OBJECTIVE: 7D3.00 To understand the structure and function of body systems and their inter-relationships

INSTRUCTIONAL OBJECTIVES: The learner will:

3.01 relate the skeleton to the tissues of ligaments and tendons.
3.02 draw and label the major bones of the skeletal system.
3.03 determine the importance of points in the skeleton to movement.
3.04 discuss the relationships of the muscular systems and skeletal system concerning movement.
3.05 name the parts of the respiratory system.
3.06 associate exhaling with the process of elimination.
3.07 identify the skin as an organ of excretion.
3.08 define digestion and list the organs of the digestive tract.
3.9 draw and label the parts of the digestive system.
3.10 discuss the exchange of substances between villi of the small intestine and capillaries of the circulatory system.
3.11 define behavior and examine the systems that control it.
3.12 learn the different divisions within the nervous system.
3.13 determine the rate of the endocrine system to the control of the body.
3.14 draw the glands of the endocrine system and define the major functions of the hormones they produce.
3.15 draw and label the human heart.
3.16 differentiate between arteries and veins.
3.17 list the type of blood cells and the function for each.
3.18 relate all systems to the transfer of their products and needs through the circulatory system.

I. Movement
A. Bones
B. Muscles
II. Elimination of Waste
A. Respiration
B. Excretion Organs
C. Skin
III. Digestion
A. The system
B. The process
IV. Control and Regulation
A. Nervous System
B. Endocrine System
V. Circulation
A. Heart
B. Blood vessels
C. Various blood cells

TN COMPONENT OF SCIENCE: Unifying Concepts of Science

TN GOAL:

To enable students to acquire scientific knowledge by applying concepts, theories, principles and laws from life/environmental, physical and earth/space sciences.

2.2 FORM AND FUNCTION - Form may determine the function of a material or a system, and function may alter form.

2.2a How an object functions is related to its form.

BENCHMARK: Specialized structures perform specific functions.

TIME REQUIRED:

Two weeks of instructional and activity time

Clock with second hand

Acne, artery, automatic nervous system, capillaries, cardiac muscle, cerebellum, cerebrum, cranial nerves, ductless glands, human anatomy, joints, ligaments, malfunction, medulla, metabolism, ossification, peripheral nerves, perspiration, smooth muscle, striated muscle, soluble, urea, urine, veins, villi

For the next few days we will be looking at the various systems of the human body. We will relate these systems to each other and to the impact they have on your well-being. Has anyone ever had the 24-hour flu? (response) How did the malfunction of your digestive system affect your life? (response) Does one upset system cause havoc in other systems in your body? (volunteer answer - responses will vary)

For the next several days we will be examining human anatomy, the structures of the human body and how they work together to keep the body alive.

The skeletal system and the muscular system work together to cause movement and locomotion. The purposes of the skeletal system are:

1. support and protect internal organs.

2. a place for muscles to attach for movement.

The joints in the skeletal system allow the system to bend and rotate. This use of joints allows free and quick movement. (Have students try to walk and sit without bending joints-IMPOSSIBLE!!)

Ligaments are tough tissues within the system that hold the bones to bones. The part of the skeleton that will give under pressure is called cartilage. (Have students push or bend nose and ears )

What would it be like to try and sleep on bone ears? (Answers will vary.)

Ossification of bone cells begins before birth. This process deposits minerals in the skeleton, giving the system strength. This process replaces most of the cartilage-like tissue with a much stronger tissue able to withstand pressure put on the body during movement. The muscular system is composed of cells and tissues that contract and relax. This contraction and relaxation causes the push and pull that results in movement. There ere two major categories of muscles: 1) Voluntary muscle- that we are able to think about and cause motion and 2) Involuntary muscles that are not controlled consciously.

What would your life be like if you had to think heart beat 40-60 times a minute? (Answers will vary - no sleep, no relaxing or playing, could think of nothing else.)

There are 3 different types of muscle tissues in the body. The striated muscles that are attached to bones and are voluntary. The smooth muscles are found in internal organs. These work within other systems such as the digestive systems and the circulatory system. They are involuntary. The third type of muscles are the cardiac muscles that are found in the heart only. These cardiac muscle tissues are involuntary and work as part of the circulatory system to cause heartbeat.

What other body systems directly depend on the muscular system? (Circulatory - heart, blood vessels; respiratory - diaphragm; digestive - smooth muscles in stomach and intestines; excretory - smooth muscles . . .)

The respiratory systems in humans causes air to move in and out of the body. There is a direct 'hook up' between the respiratory system and the circulatory system. This hook up allows an exchange between the two systems. The muscles of the diaphragm, below the lungs contracts to allow air to go into the lungs and relaxes to cause air to be pushed out of the lungs.

(Demonstrate - Use of bicycle air pump to show how a diaphragm pumps air in and out of lungs.)

(Have students draw and label the human respiratory system.)

The excretory system is actually parts of several systems. The kidneys filter all the body's blood as it passes through during circulation. It removes urea, water, and salt from the blood. The combination is urine which drains from the kidneys into the bladder where it is stored until removal from the body.

What happens to the body when the kidneys fail? (Poison builds up in the blood and can cause death!)

Why is it illegal in wrestling and football to kidney punch or clip? (Kidney damage could result.)

The skin is a very large organ for excretion. The waste the skin eliminates is called perspiration . The secretion of perspiration also aids in the cooling of the body.

The skin must be kept clean because bacteria live off of perspiration. If these bacteria are allowed to build up on the body they produce a waste known as body odor. The dirt and grime of skin can also add to the teenage problem of blackheads and acne.

The digestive system is the human body system that digests food into a soluble form. This form can be used by body cells as energy. The human body has a very "sophisticated" system developed to do this chemical process. Several organs that are not a part of the actual food tube contribute to the process. The formula for digestion is:

Food + H₂0 + Digestive Enzymes---> Soluble food + Enzymes

The enzymes involved in the digestion process are produced in glands. The salivary glands of the mouth start digestion. The glands lining the stomach secrete enzymes also, the pancreas and liver secrete enzymes into the stomach. The glands of the small intestine produce enzymes that help to finish the process. In the small intestines are thousands of villi that contain capillaries. Here is where soluble food diffuses out of villi into the blood stream. It then circulates to all body cells. Any undigested food collects in the large intestine, another excretory organ. The solid waste in the large intestine is eliminated from the body.

The nervous system is considered to be THE body controller. Actually this system work with the endocrine system to control and regulate body activities. The nervous system consists of several branches or systems working together for control.

The central nervous system is composed of the brain and the spinal cord. These two organs control the voluntary and involuntary actions of the body.

There are three parts to the brain. The cerebrum, which is the largest part of the brain. It controls things such as thinking, being aware, memory, learning, some voluntary movements and the five senses. The cerebrum is so well developed in humans that it causes man to be superior to all other animals. The cerebellum, maintains balance and muscle coordination . It is not as well developed in humans as in other animals.

Why would you get dizzy if hit on the head? (The blow could interfere with balance )

Why do squirrels have a better sense of balance than man? (They have a more developed cerebellum, thus can walk on tree branches and wires )

The medulla is at the stem of the brain and controls many involuntary actions, the secretion of glands and connects the brain to the spinal cord. The spinal cord is a thick rope of nerves that connects the brain to the rest of the body parts. Thirty-one pairs of nerves branch from the spinal cord. The cranial nerves branch into the head and the peripheral nerves branch to the other body parts. These nerves carry messages to and from the body to allow the nervous system to become aware of what is happening in the body.

The autonomic nervous system involves nerve cords on each side of the nervous system. This portion of the system regulates such involuntary actions as heartbeat, the release of hormones from glands and the action of smooth muscles in the digestive system.

The endocrine system is composed of ductless glands which produces hormones. These hormones are secreted directly into the blood streams and travel to all body parts. The main controller is a gland located in the base of the brain, the pituitary gland . It controls the other endocrine glands plus makes and secretes growth and reproductive glands. The thyroid gland is located in the throat. It regulates body metabolism. The parathyroid gland is located on the thyroid gland and regulates the calcium and phosphorus levels in the body.

The pancreas located in the abdomen contains cells called Islands of Langerhans that secrete the hormone insulin. This hormone regulates the level of sugar in the blood. Damage to these cells results in the disease called diabetes.

How is diabetes treated? (Diet, exercise and the intake of artificial insulin)

The adrenal glands are located on the kidneys. These are called the "emergency glands" because they prepare your body for emergencies.

How do you feel during and after a near accident or fright? (Very excited or nervous followed by a feeling of weakness or shakiness )

The testes and ovaries are endocrine glands that change the human body from a child into an adult. These glands control the formation of eggs and sperm for reproduction. They also cause the secondary sexual changes of the body in boys and girls.

Circulation, or the circulatory system, is related to all of the other systems because this system is the body's way of getting materials to and from all body parts. This system works 24 hours a day throughout a person's lifetime.

The purposes of the circulatory system are to transport:

1. oxygen from lungs to cells

2. soluble food from small intestines to cells

3. carbon dioxide from cells to lungs

4. water from cell to kidney

5. hormones and antibodies to all cells

The heart is the pump for this system. It is composed of cardiac muscle. The path of blood through the heart is connected to the lungs where oxygen is picked up and carbon dioxide is released. The tubes carrying blood away from the heart to the body parts are called arteries. These arteries are connected to microscopic tubes called capillaries. These microscopic tubes come in direct contact with body cells where the exchange of materials occurs. The blood then travels back through veins to the heart to start the cycle again. As the blood flows through the various organs mentioned it either picks up or releases the products involved with each organ.

The blood is composed of plasma, the liquid part of the blood, and three main types of cells. Red blood cells are the largest and most numerous. They carry the oxygen picked up in the lungs and carry CO₂ picked up from cells. The white blood cells are small and not as numerous as red blood cells. These are the cells that help fight off invaders (germs) that enter the body. The platelets are the blood cells that help blood clots form when an injury occurs. These platelets work with calcium, vitamin K and a protein called fibrinogen.

The types of helpful clots are scabs and bruises to stop the flow of blood. Some clots can do damage, such as those that cause heart attacks and strokes.

A hemophiliac lacks the ability to absorb and keep vitamin K in the blood. How would this affect the person's life? (The blood could not clot and would restrict the life of the hemophilic. Discussion of how it would restrict the person will vary.)

Speed up blood flow.

(Have students find their pulse. Do not use thumb, it is easy to find in the neck or temple. At their desk have students take pulse for 1 minute and write it down. Have students stand up and jog for one minute. When they are finished jogging, have them find and count their pulse again. Compare blood flow while resting and while exercising. Also, discuss the energy or calorie increase needed by the body during exercise.)

Materials - light microscope, prepared slides of red blood cells, white blood cells, cross-section of veins and artery.

The study of our systems and their relations to one another has involved several days and several activities. Help me name one of the systems we have studied and the other systems working with it (Answers will vary.)

acne - an outbreak on the skin, common problems during puberty

artery - blood vessel carrying blood away from the heart

autonomic nervous system - nerves associated with spinal nerves

capillaries - microscopic blood vessels that are in direct contact with body cells

cardiac muscle - muscle of the heart

cerebellum - part of brain for balance and muscle coordination

cerebrum- largest part of human brain

cranial nerves - nerves in face and head

ductless glands - glands that secrete their product directly into the blood stream

human anatomy - study of the structure of the body

joints - where two bones meet

ligaments - holds bone to bone at a joint

malfunction - does not function correctly

medulla - stem of the brain, controls many involuntary actions such as the secretion of glands, connects the brain to the spinal cord

metabolism - rate at which cells use food

ossification - process of depositing calcium around bone cells for strength

peripheral nerves - nerves connecting the spinal cord to body parts

perspiration - excretion from skin to cool the body, commonly called sweat

smooth muscle - involuntary in organs

soluble - form of food that is small enough to diffuse through a cell membrane

striated muscle - voluntary muscles

urea - waste filtered from the blood by the kidneys

urine - a combination of urea, water and salt filtered from the blood

veins - blood vessels that carry blood back toward the heart

villi - tiny finger-like projections in the walls of the small intestine

This is the time this file has been accessed since 04/02/98.

The University of Tennessee at Martin is not responsible for the information or views expressed here.

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