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
Complex carbs:
Glycogen:
- Polysaccharide
- Highly branded chains of glucose
- found in muscle and liver
- broken down quickly when body needs glucose
Starches:
- either straight chains or branches chains of glucose. Ex) pasta
Fibre:
- straight or branched chains of monosaccharides, but the bonds that link the sugar units cannot be broken by the human digestive enzymes. Ex) broccoli
During Digestion _______ break down _____ and _____ into _________
Enzymes, starches, sugars, monosaccharides
____ ____ starts breaking down Starch into shorter__________
Salivary amylase, polysaccharides
Pancreatic Amylases completes the breakdown of _____ into __________ and short chains of sugar units call ______________
starch, disaccharides, oligosaccharides
______ attached to the brush border of the ______ villi complete digestion of carbohydrates into monosaccharides
Enzymes, small intestinal
____ _____ and other indigestible carbs are partially broken down by bacteria to form _____ __________ ________
Soluble fibre, short chain fatty acids and gas
________ and any ____ that are not digested and/or absorbed are excreted in the feces.
Insoluble fibre, carbs
Glucose
Used for quick energy or is converted to glycogen and stored in the liver and muscles.
Recommended Dietary Allowance (RDA) for carbs
130g/day
5-6grams per kg of body weight
If you have ‘adequate’ carbohydrate intake…
Protein is reserved for building & maintaining muscles and organs.
If you have ‘inadequate’ carbohydrate intake…
Need energy from somewhere, causing body to make glucose from proteins.
Can cause muscle atrophy
The carbs in foods we eat provide _____?
Glucose
Insulin pathway
Increased blood glucose –> insulin secretion –> glucose taken into cells –> decreased blood cells
Glucagon pathway
Decreased blood glucose – . glucagon secretion –> Glucose released from liver –> increased blood glucose
Fructose is found in?
Fruit and honey
Glucose is ?
The simplest sugar (photosynthesis)
Glucose + fructose = sucrose
Fructose is…
Metabolized primarily by the liver. immediate effect on triglycerides (fat in blood and stored in fat cells) Leads to a fatty liver Decreased insulin sensitivity Increased levels of uric acid (Gout)
Glucose is…
Metabolized by the brain, muscles, fat tissue and the liver
Enters the blood stream fast
Triggers insulin release.
High fructose corn syrup
From cornstarch (chains of glucose)
Enzymes are added to covert glucose to fructose
HFCS is 42-55% fructose
4 Serious health issues related to sugar
- High blood pressure
- High cholesterol
- Excess sugar is converted to triglycerides (fat in bloodstream) - Liver disease
- extra sugar stimulates triglyceride production in liver - Diabetes
Type 1 Diabetes
Elevated blood glucose, absolute insulin deficiency.
Autoimmune destruction of insulin-secreting cells in the pancreas
5-10% of diagnosed cases
before the age of 30
What is ketacidosis
low insulin levels which leads to low glucose inside of cells leading to ketone formation & high blood acidity.
Type 2 Diabetes
- insulin resistance; relative insulin deficiency
- 90-95% of all cases
- Extra sugar spikes insulin from pancreas
- Spiking too often leads to resistance to the process
Insulin loses its ability to draw sugar from bloodstream - Sugar hangs out in blood and corrodes the arteries… Leading to diabetes and cardiovascular disease
What happens to blood glucose levels in people with diabetes 8 hours after fasting:
Normal blood glucose is less than 100 mg/100 ml blood
Prediabetes = a fasting blood level from 100 to 125 mg/100 ml
Diabetes = a fasting level of 126 mg/100 ml or above
What happens to blood glucose levels in people with diabetes 2 hours after consuming 75g of glucose:
Normal blood levels are less than 140 mg/100 ml
Prediabetes levels are from 140 to 199 mg/100 ml
Diabetes levels are 200 mg/100 ml or greater
4 Key modifiable risk factors for type 2 diabetes
Physical Inactivity - exercise enhances muscles using sugar Unhealthy eating - consumption of too many simple cards Tobacco smoking - Kills your pancreas and affects insulin production Overweight and Obesity - toxins interfere with insulin production and process Family history
What is considered a healthy WHR? (waist to hip ratio)
Is a hip/waist measurement 0.9 or less for men
- 85 or less for women
* Will I need to know the BMI measurement chart?**
In 2008/2009 how many Canadians had diabetes?
2.4million or 6.8%
five risk factors that increase the likelihood of developing:
heart disease, diabetes, and stroke.
The five risk factors are:
- increased blood pressure (greater than 130/85 mmHg)
- high blood sugar levels (insulin resistance)
- excess fat around the waist
- high triglyceride levels
- low levels of good cholesterol, or HDL
Our bodies can move about _______ of glucose through our blood every hour, which is the equivalent of a piece of fruit.
20 grams
Glycemic load
compares food portions
Fibre
Cannot be broken down in digestive process
Absorbed in small intestine… then passes thru to the large intestine, virtually unchanged
Benefits of fibre
Promotes Bowel Regularity
Weight Control & Reduces Obesity
Reduction of Constipation, Hemorrhoids
Reduction of Diabetes (key-blood glucose regulation)
Reduction of Colon Cancer (key-phytochemicals)
Reduction of Heart Disease (inhibits cholesterol absorption)
Water soluble fibre
Found ‘inside’ plant cells
(Citrus fruits, apples, bananas, carrots, barley, beans, oat products)
Promotes heart health by binding fatty acids cholesterol & excreting it
Regulates blood sugar levels (lower risk of Type 2 Diabetes)
Water insoluble fibre
From ‘structural part’ of plants (or the outside)
Whole grains, bran, wheat, rye, rice
Vegetables like broccoli & celery
Promotes intestinal health
Binds toxins, promotes regularity
How much fibre should one eat per day?
25 – 35 grams per day
(Men = 35 g/day; Women = 25 g/day)
(Age + 5 grams) per day
(i.e. 7 year old = 7 + 5 = 12 grams)
Lactose intolerance
Low levels of small intestine enzyme lactase
The disaccharide lactose cannot be broken down into monosaccharides
Lactose passes into the large intestine where it is digested by bacteria
What is gluten?
Gluten is one of the proteins found in grain products:
wheat, barley, rye
Celiac disease is a _____?
autoimmune disease
Gluten intolerance?
also known as non-celiac gluten sensitivity, has similar symptoms to celiac disease.
Wheat allergy experience:
a response (by the immune system) to a number of food proteins found in wheat, including gluten.
What is the liquid produced by the liver that aids in the digestion and absorption of fat? Where is it stored?
Bile - helps the body absorb fat into the bloodstream. It is stored in the gallbladder.
What is part of the digestive tract is responsible for the final deconstruction of proteins into amino acids, carbohydrates into glucose and fats into fatty-acids & glycerol? What are the Pancreatic enzymes for each macronutrient?
Small intestine -jejunum and ileum.
Pancreatic amylase - carbs
Pancreatic proteases - protein
Pancreatic lipases - fats
Bicarbonate - in the small intestine
neutralizes the acid in the chyme (from the stomach)
