Exam #2 Flashcards
What are the 4 main components of the digestive system?
- Gastrointestinal tract
- pancreas, gall bladder, liver,
- enzymes, hormones, nerves and blood
- Mesentery
Where does the digestive process begin?
Before food even hits your tongue. Glands produce saliva.
Once inside then mushes it to bolus. Enzymes in the saliva break down any starch.
What is bolus and what does it become in the stomach?
It is a yellowish-green liquid that breaks down fat. It becomes chyme.
Where does protein digestion begin (what is the enzyme that starts the process)?
Begins with the action of an enzyme called pepsin. Pepsin is the active protein-digesting enzyme of the stomach. Then once it reaches the stomach the enzyme protease breaks the protein to smaller chains of amino acids.
Mouth
Chews food and mixes it with saliva
Salivary glands
Produce saliva which contains a starch-digesting enzyme
Pharynx
Swallows chewed food mixed with saliva
Esophagus
Moves food to the stomach
Stomach
Churns and mixes food; secretes acid and a protein-digesting enzyme
Liver
Makes bile, which aids in digestion and absorption of fat
Pancreas
Releases bicarbonate to neutralize contents; produces enzymes that digest carbohydrate, protein and fat`
Gallbladder
Stores bile and releases it into the small intestine when needed
Small intestine
Absorbs nutrients into blood or lymph; most digestion occurs here
Large intestine
Absorbs water and some vitamins and minerals; home to intestinal bacteria; passes waste material
Anus
Opens to allow waste to leave the body
Food that enters the GI tract is still considered external to the body until it is absorbed by the _____ (muscosal cells) in the ______
Mucosa, lumen
The lymphatic system
Maintains balance of fluid between the blood and tissues, known as fluid homeostasis.
Forms part of the body’s immune system and helps defend against bacteria and other intruders.
Facilitates absorption of fats and fat-soluble nutrients in the digestive system.
Pancreatic amylase
Digests carbs into sugars
Pancreatic proteases
digests proteins into amino acids
Pancreatic lipases
Digests fats into fatty acids
Empty calories
Food that contains energy but few additional nutrients
Refined sugars
Contain calories but lack fibre, phytochemicasl and other nutrients
What are carbohydrates? (hint: plant + sun)
- Leaves capture sun’s energy + Carbon dioxide & water
- Plants convert glucose to starch
- Humans eat plants and covert starch back to glucose
- ‘Glucose’ is a primary fuel we use for energy (CHO)
Whole grains
Contain the: endosperm(starch, protein, and vitamins and minerals), bran (fibre, vitamins and minerals), and germ (oil, vitamin E)
Refined grains
Only contain the endosperm (starch, protein and vitamins and minerals)
Polysaccharides
are made up of more than two sugar units linked together
Monosaccharides and disaccharides are classified as _____ _________
Simple carbohyrates
The most common monosaccharides in our diet are ______, ________ and ________.
glucose, fructose and galactose
The most common disaccharides in our diet are _______, _______ and _______
maltose, sucrose and lactose