Digestive System Flashcards
what is Catabolism?
The breakdown of larger molecules to release energy
What is Anabolism?
The building of larger molocules to store energy
What is Metebolic rate?
The rate at which the body converts stored energy into working energy
what is ingestion?
When food enters the mouth
What is digestion?
Breakdown of food into smaller molecules
What are the two kinds of digestion?
Mechanical and Chemical
What is mechanical digestion?
The pysical breakdown of food into smaller peices (ect. mouth and stomach)
What is chemical digestion
The breakdown of large molecules using water and enzymes
what is absorption
Nutrients being absorbed into the bloodstream
what is egestion?
The removal of waste products.
Nutrients can be divided into two groups:
Organic compounds and Inorganic compounds
Organic compounds:
Made of C, H, O, Needs to be broken down before absorption
Inorganic Compounds:
can be absorbed directly into the blodd streem (no digestion needed)
Proteins are made from:
a long chain of amino acids connected by Peptide bonds
Proteins are responsible for:
Building and reparing muscle
Growing and developing
Enxymes and Hormones
Incorporated into cell membrane
Carbohydrates (Polysaccharides) are made from
A long chain of sugar units connected by Glycosidic bonds
Carbohydrates (Polysaccharides) are responsible for:
The main source of energy
Fats / Lipids are made from:
Fatty acids and glycerol connected by an ester bond
Fats / Lipids are responsible for:
Cell membranes and a source of longer term energy storage
What are Enzymes?
Biological catalysts (Proteins) that regulate the rate of a chemical reaction within the body (metabolism).
Proteins that regulate your rate of metabolism.
Enzyme structure (Active site)
The active site is the area with a specific shape, this allows for only one specific substrate to bind with the enzyme
How Enzymes work
Substrate sticks to enzyme, breaking, rearraging or rebulding the substrate, then releasing the new substrate
what is Catalysis
The breaking, rearraging or rebuilding of a substrate
The Mouth
Mechanical (chewing moving food) chemical (siliva, Amylase)
what is Amylase used for
Alylase is found in Salivia, It breaks down Polysaccharides into disaccharides.
Bolus
Moist ball of food
The Epiglottis
Covers the trachea when swallowing, it prevents food from entering the lungs
The Esophagus
A long muscular tube that connects the mouth to their stomach
Esophagus (peristalsis)
Smooth muscle that produces a wave of contractions that push food to the stomach.
The stomach
an expandable “Bag”
Ph of 2, makes mucus to protect from acidity
what is Rugae?
small folds in the stomach that allow for expansion.
Sphincters
Are the “entrance and exit” of the stomach
Esophageal; controls food entering
Pyloric: Controls food leaving n
Stomach: Chemical digestion
Secretes gastic juices that disolve food
Stomach: Mechanical Digestion
Churning to mix food
Pepsin
pepsin is an enzyme that breaks down proteins, If the cells linning the stomach where to create pepsin it would break down the stomach membrane aswell.
pepsinogen
an inactive form of pepsin, that mixes with HCI and converts to the active form…Pepsin.
Small Intestine
Primary site of absorption and digestion
3 main sections
1. DUODENUM
2. Jejunum
3. Ileum
Small intestine: Duodenum
10 inches long (adults)
where chemical digestion happens
Has glands and microvilli
Small intestine: Jejunum & Ileum
Finger like projections called microvilli (for increasing surface area = more nutrients)
Main responsibility: Absorption of nutrients
The large Intestine
3 sections:
Ascending
Transverse
Descending
Role: water and vitamin absorption
