Download Digestive-Excretory Test Review Key

Review Key: Digestive and Excretory Systems
Study Chapters 1-5 in human body book as well as any additional activities, labs, or diagrams that we have
completed since we began this unit.
1.
What are the functions of the digestive system?
Breaking down food into molecules the body can use
Absorbing food molecules into the blood
Eliminating undigested wastes from the body
2. Where does digestion begin? Mouth
3. What are the waves of contraction as food is pushed down the esophagus called? peristalsis
4. How does the structure of teeth relate to their function?
Front teeth are thinner and used for cutting. Molars are flatter & wider for grinding.
5. What is the purpose of mucus in the stomach?
To provide a protective lining from the hydrochloric acid in the stomach
6. What is the advantage of the stomach being a muscular structure?
It is able to churn and mix food with digestive juice
7. What is the purpose of villi?
Enables the small intestine to absorb large amounts of nutrients
8. Where does most chemical digestion take place? Small intestine
9. What is the main function of the excretory system? Eliminate metabolic wastes from the body
10. What are the main substances found in urine? Urea, excess water, salts
11. What is a nephron? filtering tubes in the kidneys
12. Describe the filtration & urine production process in the kidneys.
 Urea travels from liver to kidney in blood
 As blood enters the kidney, it is forced through capillaries filtering out urea, excess water,
and salts as they pass through millions of filtering tubes called nephrons.
 Wastes that remain in the nephrons are considered urine.
13. Which excretory organ eliminates water and some chemical wastes through perspiration? skin
14. How do the kidneys help maintain water balance on a hot day?
By keeping water in the bloodstream to help with hydration
15. Use the diagrams below to identify structures for the chart on the back. If a structure is not found in the
diagrams below, please write NH for Not Here.
Organ
1.Mouth
System
Dig. Or Exc.
D
Letter
on
Picture
Function(s)
Ingestion, mechanical
digestion, chemical
digestion, absorption or
elimination
NH
Mechanically breaks down food by chewing
Wets the food with saliva
Chemically breaks down food with enzymes in saliva
CD
I/MD/CD
2.Saliva
D
NH
fluid that is released to help break down food
chemical digestion- enzymes in saliva
mechanical digestion- soften the bolus for easier swallowing
3.Teeth
D
NH
start tearing and crushing the food down into small enough pieces so that it
can fit down our throats
MD
4.Epiglottis
D
NH
A flap that closes over the top of the trachea (windpipe) when swallowing,
so that food does not enter the respiratory tract
----
5.Esophagus
D
A
Involuntary smooth muscles contract and push food toward the stomach
(peristalsis)
MD
D
B
The lining releases digestive juice, which contains:
• Pepsin- Enzyme that breaks down protein
• Hydrochloric Acid (HCl) - Strong Acid to kill any bacteria you may have
ingested
Thick stomach muscles create a churning motion to mechanically digest food
MD/CD
D/E
NH/NH
Blood Vessels are found within the villi of the small intestine so they absorb
nutrients and deliver to the entire body
A
6. Stomach
7. Blood
8.Pancreas
Attached near the first part of the small intestine
Produces enzymes that help breaks down starches, fat and proteins that
goes into the small intestines
Does not break down fiber
Dig- Produces Bile- breaks up fat particles into small droplets
Exc- Produces urea (compacted nitrogen produced in the breakdown of
protein); Regulates sugar in blood; Breaks down old red blood cells and
poisons and sends them to the kidneys for disposal
D
C
D/E
G/NH
D
NH
Stores bile until sent to small intestine
Helps with CD
D
E
Peristalsis to push the food through
Chemical Digestion through enzymes
Absorption of nutrients to the blood
MD/CD/A
D
F
large amounts of water are removed
A
13. Rectum
D
D
Stores solid wastes (feces) until ready to exit the body
E
14. Anus
D
NH
Where solid wastes (feces) exits the body
E
15. Kidneys
E
A
Main organ of the excretory system – filters blood & regulates water balance
E
16. Ureters
E
B
The nephrons move urine to tubes (ureters) that connect the kidneys to the
bladder
E
E
C
Muscular, stretchy organ that stores urine for disposal
E
18. Urethra
E
D
A tube where urine leaves your bladder and exits the body
E
19. Skin
E
NH
Releases Urea, Salts, Water, & Heat through sweating
E
20. Lungs
E
NH
Releases Carbon Dioxide, Water & Heat through exhalation
E
9.Liver
10.Gallbladder
11.Small
Intestine
12. Large
Intestine
17. Urinary
Bladder
Helps with CD
Helps with CD