The HUMAN BODY
Chapter 30
Digestive and Excretory Systems
Chapter 30.1 Organization
• Objectives
– Describe how the human
body is organized.
– Explain homeostasis.
ORGANIZATION
•
•
•
•
•
Cells
Tissues
Organs
Organ Systems
Organisms
Tissue Types
• Muscle Tissue- can contract
and shorten for movement
• Connective Tissue- provides
support and connects all parts
of the body
• Nerve Tissue- carries
messages back and forth from
body to brain and spinal cord
• Epithelial Tissue- forms a
protective surface inside and
outside of the body (glands,
too)
Organ Systems
• Organs made of tissue make up
the organ systems:
• These systems are interconnected
–
–
–
–
–
–
–
–
–
–
–
Skeletal
Muscular
Integumentary
Digestive
Circulatory
Respiratory
Excretory
Immune
Endocrine
Nervous
Reproductive
Homeostasis
• Process by which
organisms keep
internal conditions
relatively constant
(balance)
– Ex. Shiver when
cold to heat up
Check-in
What tissue type:
– Carries messages between brain and body
• Nervous tissue
– Provides support and connects parts of body
• Connective tissue
– Contracts and shortens for movement
• Muscle tissue
– Forms protective surface
• Epithelial tissue
Chapter 30.2 Food Nutrition
• Objectives
– Identify essential nutrients
needed by your body and
explain how each is
important
Nutrition
• Food supplies us
with the following:
– Energy
– Materials for body
processes
• Growth
• Repair
• Maintenance
Nutrients
•
•
•
•
•
•
Water
Carbohydrates
Fats (Lipids)
Proteins
Vitamins
Minerals
Check-in
• What two things does food supply us with?
– Energy and raw materials for body processes
• What is the most important nutrient?
– Water
• Organic molecule that regulates body processes
– Vitamins
• Main source of energy
– Carbohydrates
Chapter 30.3 Digestive System
• Objectives
– Describe the organs of the
digestive system and their
functions.
– Explain what happens during
digestion.
– Describe how nutrients are
absorbed and wastes are
eliminated.
Digestive System
• Function: To break down
and absorb nutrients from
food to provide the body
with energy
Types of Digestion
• Mechanical Digestion:
– Food is physically
broken into smaller
pieces
– Ex. Teeth
• Chemical Digestion:
– Food is changed at the
molecular level
– Ex. Gastric Juices
Path of Digestion
• Mouth
– Mechanical: use teeth and
tongue to mechanically break
down food
– Chemical: saliva breaks
starchessugars
• Esophagus
– Passage from mouth to stomach
– Adds mucous to ball of food
Path of Digestion
• Stomach
– Chemical: Gastric juices
(Pepsin and Hydrochloric
Acid) to break down
proteins
– Mechanical: Stomach
churns food into a soupy
substance: chyme
Path of Digestion
• Small Intestine
– Food is broken down with various juices
and then the nutrients are absorbed
*lined with villi- finger-like projections that
increase surface area for absorption
– Mechanical: Bile from the liver/gall
bladder emulsifies fats (breaks into globs)
– Chemical: Intestinal and Pancreatic juices
break down fats, carbohydrates, and
proteins
Path of Digestion
• Large Intestine
– Absorbs water and
vitamins from
undigested waste
• Rectum
– Storage area for waste
• Anus
– Place where waste
exits the body
Accessory Organs of Digestion
• Salivary Glands
– Produce salivary amylase to break
down carbohydrates
• Liver
– Produces bile to emulsify fats
• Gall Bladder
– Stores the bile made by the liver
• Pancreas
– Produces pancreatic juices to
break down fats (Lipase), carbs
(Amylase), and proteins (Trypsin)
Digestion Video
http://www.youtube.com/watch?v=XxvRbxhqoZk&feature=r
elated
Check-in
• Type of digestion in which food is
physically broken into smaller pieces
– Mechanical digestion
• Trace the path food takes on its trip through
the digestive system
– Mouth esophogusstomachsmall
intestinelarge intestinerectumanus
Check-in
• Where are proteins digested (and by what)?
– Stomach (gastric juice – pepsin/HCl),
Sm. Intestine (pancreatic juice – trypsin)
• Where are carbs digested (and by what)?
– Mouth (amylase),
Sm. Intestine (pancreatic and intestinal juice)
• Where are fats digested (and by what)?
– Sm. Intestine (pancreatic juice)
Check-in
• Where is bile made / stored?
– Made in liver and stored in gall bladder
• Where are nutrients absorbed?
– Small intestine (major of nutrients) and
large intestine (water and vitamins)
• Describe the mechanical digestion in each
organ of digestive system.
– Mouth (chewing), stomach (churning by
muscles), Sm. Intestine (bile emulsifies fat)
Chapter 30.4 Excretory System
• Objectives
– Describe the organs of the
excretory system and their
functions.
– Describe how the kidneys
maintain homeostasis.
EXCRETORY SYSTEM
• Function
– Removes various wastes
from the body to maintain
homeostasis
– Ex. Urine, Sweat, Breath
Video clip
Main Excretory Organ
• Kidneys– filter waste (urine) from
blood
• enters through renal artery
• exits through renal vein
*Nephrons- individual filtering
units of kidney
– maintain blood pH
– regulate blood volume
Other Excretory Organs
• Liver- filter wastes
from blood,
detoxifies
• Skin- excretes
sweat, oil
• Lungs- remove
H2O and Carbon
Dioxide
Check-in
• What are the functions of the kidney?
– Filter wastes from blood, regulate blood pH,
regulate blood volume
• What organ excretes carbon dioxide and
water?
– Lungs
• What organ detoxifies the blood?
– Liver