Digestive System Flashcards
3 phases in Digestive System
1) Digestion
2)Absorption
3) Elimination
Organ which absorbs water and vitamin K from digested food
Large intestine
Organ which produces enzymes that break down nutrients
pancreas
Tiny blood vessels transport absorbed nutrients
capillaries
Cells which produce hydrochloric acid (HCI)
parietal cells
cells which produce pepsin
chief cells
Pepsin function?
break downs proteins
How is the energy of food measured?
Calories (food calories)
Calories are found in which 3 main nutrients in food?
carbs (sugars and starches)
proteins
fats (lipids)
Peristalsis
the muscular contractions that push food through the digestive system
mechanical digestion
teeth and muscular contractions in stomach break down food into smaller partials PHYSICALLY
chemical digestion
powerful chemicals break down food
Pancreases produces which 3 digestive enzymes?
amylase
lipase
protease (trypsin AND chymotripsin)
Amylase is an enzyme produced from the…
pancreas
Trypsin is an enzyme produced from the…
pancreas
Lipase is an enzyme produced from the…
pancreas
The enzyme Amylase breaks down…
complex carbs –> simple carbs (sugars)
The enzyme Trypsin breaks down…
proteins into amino acids
The enzyme lipase breaks down… (2)
fats into fatty acids and monoglycerides
When food chunks turns into a liquid in the stomach’s churning process, it becomes
chyme
why are fat molecules difficult to break down?
fat does not mix well with water based enzymes
What allows lipase to work on breaking down fat?
fat to be broken down into smaller droplets
How can fat be broken down into smaller droplets allowing lipase to do its job
bile allows it to be broken down more
What is bile
yellowish green digestive fluid which breaks down fats
where is bile produced
liver
where is bile stored
gallbladder
Which organ allows NUTRIENTS and WATER to pass through walls
small intestines
Which small organs transport absorbed nutrients into the bloodstream
capillaries and lymphatic vessels
Capillaries absorb…
sugars, amino acids and water
Lymphatic vessels absorb…
fatty acids
Duodenum
the first part of the small intestine
What is the primary function of the digestive system?
To break down food into nutrients that the body can absorb.
True or False: The digestive system includes both mechanical and chemical processes.
True
Fill in the blank: The digestive system begins in the ______.
mouth
What is the role of saliva in digestion?
Saliva contains enzymes that begin the breakdown of carbohydrates.
Which organ is primarily responsible for nutrient absorption?
Small intestine
What are the three main sections of the small intestine?
Duodenum, jejunum, ileum
Multiple choice: Which of the following organs produces bile? A) Pancreas B) Liver C) Gallbladder
B) Liver
What is the function of the stomach in the digestive process?
To store and mix food with gastric juices for digestion.
True or False: The esophagus is responsible for the absorption of nutrients.
False
What is the role of the pancreas in digestion?
To produce digestive enzymes and bicarbonate to neutralize stomach acid.
Fill in the blank: The large intestine is primarily responsible for ______.
water absorption and waste elimination.
What is the purpose of the rectum in the digestive system?
To store feces before elimination.
Multiple choice: Which enzyme breaks down proteins in the stomach? A) Amylase B) Pepsin C) Lipase
B) Pepsin
What is peristalsis?
The wave-like muscle contractions that move food through the digestive tract.
True or False: The gallbladder stores bile produced by the pancreas.
False
What is the primary role of dietary fiber in digestion?
To promote regular bowel movements and aid in digestion.
Fill in the blank: The ______ is a muscular tube that connects the throat to the stomach.
esophagus
What are villi and their function?
Tiny finger-like projections in the small intestine that increase surface area for absorption.
Multiple choice: Which part of the digestive system is responsible for the fermentation of undigested food? A) Stomach B) Large intestine C) Small intestine
B) Large intestine
What is the significance of the liver in digestion?
It processes nutrients absorbed from the small intestine and produces bile.
True or False: The digestive process begins in the stomach.
False
What is the role of the small intestine in the digestive system?
To further digest food and absorb nutrients into the bloodstream.
Fill in the blank: The ______ is the last section of the digestive tract.
anus
What is chyme?
A semi-liquid mixture of food and digestive juices in the stomach.
Multiple choice: Which vitamin is primarily absorbed in the large intestine? A) Vitamin C B) Vitamin K C) Vitamin B12
B) Vitamin K
What is the function of gastric acid?
To create an acidic environment for enzyme activity and to kill pathogens.
What are the three main sections of the small intestine?
Duodenum, jejunum, and ileum.
True or False: The primary function of the small intestine is the absorption of nutrients.
True.
Fill in the blank: The small intestine is approximately ______ meters long in adults.
6 to 7 meters.
Which section of the small intestine is primarily responsible for digestion?
Duodenum.
Protease (enzyme of three produced in pancreas) come in two types…
trypsin
chymotrypsin
Feedback loops
the output of a process influences the input a cycle helping maintain stability (homeostasis)
Homeostasis
maintenance of relatively stable internal environment
Stimulus
a change in environment causing a response
two types of feedback loops
1) positive feedback loops
2) negative feedback loops
Positive feedback loops
response amplifies the change moving system FURTHER FROM original state
Negative feedback loops
response that brings conditions back to original state (make less)
True or False:
Positive feedback loops are stable systems
False.
Positive feedback loops are inherently UNSTABLE systems
True or False
Positive feedback loops are unstable systems (why)
True.
- Can lead to runaway process because there might be no counter-balancing reaction
- conditions
- amplifies
- can potentially harm
True or False
Negative feedback loops are unstable
False
Negative feedback loops are stable
True or false
negative feedback loops are stable
TRUE
Most biological feedback systems are…
negative feedback systems
Excretory system
excretes wastes from the body, regulating the amount of water and ELIMINATES FROM BLOOD the wastes produced by METABOLISM
Define Excretory system
Body system that removes metabolic wastes from the body
name the major digestive system parts in order
after stomach list the accessory organs of digestive system
- oral cavity
- esophagus
- Stomach
Accessory organs
- Liver
- Gall bladder
- pancreas
- small intestine
- large intestine
- anus
Kidneys function
filters blood and regulate water balance
Other organs that are involved in excretion
skin, lungs, liver
Skin excretion does…
the removal of excess water and salt via sweat
Lungs in exertion does…
the removal of carbon dioxide which is exertion by exhaling
liver in exertion…
breaks down toxic substances in blood and convert convert nitrogenous waste in urea
Urinary tract function
major part of excretory system
filters wastes and water from blood and eliminates them from the body
Urinary tract organs in order
kidney
ureter
bladder
urethra
Kidneys produce
waste called urine using nephrons
What do digestive enzymes do?
create chemical reactions that help break down food, building muscle, and more
Enzymes are
a protein found within a cell which create chemical reactions
The three enzymes produced in the pancreas
Amylase
Protease
Lipase
Where are digestive enzymes created
pancreas
Amylase breaks down…
starches and carbs into sugar
protease breaks down…
protein into amino acids
lipase breaks down …
lipids (fats oils) into glycerol and fatty acids
Amylase is produced in pancreas but also in the…
salvary glands
Protease is produced in
the stomach, pancreas and small intestine
Pepsin is located and does what function
in the stomach, main digestive enzyme attacks proteins
Lipase is produced in …
pancreas and small intestine
True or false
enzymes are proteins that help slow down metabolism
false
they help to speed up metabolism
Enzymes have a active site, the substance an enzyme works on is called…
substrate
the enzyme and substrate must fit to work
How do temperature and pH affect enzymes?
when the conditions are not right for the enzyme, IT CHANGES SHAPE
causing it to not fit in substrates which means it don’t work
pH and enzymes
enzymes work in a environment not too acidic or basic.
temperature and enzymes
Enzymes works best at 98.6, as it increases enzyme reaction increase
Common enzymes made in small intestine
lactase (breaks down lactose)
sucrase (breaks down sucrose)
do enzymes slow down or speed up chemical reactions?
enzymes speed up chemical reactions, they act as catalysts
Activation energy meaning
the amount of energy needed to get a chemical reactions started
How is reactions rates sped up?
by lowering activation energy
all reactions require…
activation energy
Steps of how enzymes lower the activation energy needed… (4)
- orienting substrates correctly (for successful collision)
- straining substrate bonds (easier to break)
-providing a favorable microenvironment (acidic or basic residues)
- participating directly in the chemical reactions (forming temporary covalent bonds with substrates)
Enzyme-substrate complex
the temporary association between enzyme and substrate which lowers the activation energy
what happens after the enzyme substrate complex?
products are released and enzymes return to its original shape
competitive inhibitors
?
bind to the active site COMPETING w SUBSTRATE
structured similarly to substrate and prevents substrate binding
noncompetitive inhibitors
?
bind to different site on enzyme (allosteric)
changes enzymes shape, altering the config
so SUBSTRATE CANNOT BIND EFFECTIVELY
impact on enzyme activity with competitive inhibitors ?
increases the substrate concentration
does not affect maximum reaction rate
noncompetitive inhibitors affect on enzyme activity
decreases substrate concentration while not affecting the maximimum rate
