Download Integumentary System Skeletal System Muscular System Digestive

Integumentary, Skeletal, Muscular, Digestive, and Excretory Systems
Notes
Integumentary System
Layers of the skin:
-Epidermis: outer layer of the skin
-Dermis: under the epidermis, contains many small structures
such as blood vessels, nerves, hair follicles, muscle fibers
(attached to hair follicles), oil glands, and sweat glands
-Hypodermis: attaches the skin to bone and muscle
-hair and nails protect your skin, eyes, and nose
-helps maintain body temperature
Skeletal System
-bones are made of living cells and tissues
-bones protect and support your body and store fat
-Red marrow in bones makes red and white blood cells
Muscular System
-muscles can be voluntary or involuntary
-smooth and cardiac muscles are involuntary
-skeletal muscles can be both voluntary and involuntary
-skeletal muscles work in pairs to cause smooth, controlled
movements
-muscles contract and relax to cause movement
Digestive System
Physical and Chemical Changes
Physical Change
-a change in which the identity of a substance does not change
-change of state (solid, liquid, gas)
-change of shape or size (if you cut paper, it is still paper)
-a mixture where the substances do not combine chemically (sugar
and water)
Chemical Change (Reaction)
-a chemical reaction where substances combine to make a completely
new substance with different properties
-the identity of the substance is changed
-when you burn a piece of wood, the heat chemically changes the
wood and oxygen into ash and smoke
-oxidation (rust)
-signs of a chemical change: gas bubbles, change in color, heat,
formation of a solid, sound, odor
How the Body Breaks down Food
Mechanical Digestion
-process that breaks large food particles into smaller particles by
chewing and smashing (smaller parts of the same food item)
-food is crushed and liquefied by the movement of the teeth, tongue,
and peristaltic contractions (waves of involuntary muscle
contractions) of the stomach and small intestine
-this creates a greater surface area for digestive enzymes to work on
for chemical digestion
Chemical digestion
-process that breaks large food particles into smaller molecules that
can be taken in by cells (change in the identity of the substance)
-many organs in the body are involved in breaking food into particles
that can be absorbed
-enzymes in saliva start to break down starch into sugars
-enzymes and acids in stomach break down food into smaller
molecules (like proteins, carbohydrates, and lipids)
-in the small intestine, more enzymes are secreted to break down the
molecules into even simpler ones (for example, lipids into fatty acids)
-the nutrients are then absorbed into your bloodstream through the
villi in the small intestine
-the liver, pancreas, and gall bladder produce and store bile and
digestive enzymes
-the pancreas also produces insulin
-the liver also stores nutrients and filters blood
Types of Energy
Kinetic-energy of motion
Mechanical-energy of matter because of its motion or position
Radiant-energy of light (electromagnetic waves)
Thermal-energy of temperature (particles in hot water move
faster than particles in cold water)
Electrical-energy produced by electrical charges (movement of
electrons)
Potential-stored energy
Gravitational Potential Energy-energy based on an object’s
position above the Earth
Chemical-energy stored in matter because of its chemical
makeup (food, fossil fuels)
Energy Transformations
-the energy in matter can change, or transform, from one form to
another
-energy cannot be created or destroyed, it just changes forms
-when you “use” energy, you are really just transforming it to another
form
-in a flashlight, the chemical energy of the battery is converted into
electrical energy which is then converted into radiant (light) and
thermal energy
-radiant energy from the sun is converted into chemical energy stored
in plants during photosynthesis
-often in energy transformations, some energy is “lost” to thermal
energy (this means that heat is given off during an energy
transformation even though heat is not needed)
Energy Transformation inside of you
-the food you eat is chemical energy
-your digestive system breaks the food down into molecules that are
the nutrients and energy you need for survival
-the chemical energy in your food is converted to different chemical
energy and thermal energy
-the thermal energy is given off as heat
-the chemical energy (molecules such as carbohydrates) travels
around your body in your circulatory system until it is used by various
cells
-the cells then use that energy to allow body movement
-this is when the chemical energy is transformed into mechanical
energy
-skeletal muscle cells contract and relax to allow movement
-blood cells travel through the blood vessels to provide more energy
and nutrients to other cells
-smooth muscle cells in the digestive system move food along to
continue the process of energy conversion
The human body is able to convert chemical energy stored in food into
mechanical energy so a person can move and thermal energy given
off as heat.
Excretory System
-kidneys filter waste from the blood
-water, salt, and urea are excreted through the bladder
-sweat glands can release urea