Chapter 3 Flashcards
What are the 5 chemical tastes?
1)Sweet
2)Sour
3)Bitter
4)Salty
5)Umami (MSG)
What is Flavour?
Flavour is the total sensory impression when a food is eaten
What are 4 elements of flavour?
1)Aroma (smell more sensitive than taste)
2)Texture
3)Temperature
4)Taste
Why do people like Sugar Fat and Salt?
Encourages adequate energy intake
-However can lead to overconsumption
Why do people avoid bitterness?
Discourages consumption of foods containg bitter toxins
What are the 2 roles of the digestive system?
1)Digest (break molecules of food into smaller molecules)
2)Absorb (movement of nutrients into intestinal cells after digestion)
Where does mechanical digestion begin?
Mouth
What is the role of salvia?
Softens rough/sharp foods
Salvia moistens and coats foods
What is the role of mastication?
Releases nutrients trapped inside indigestible skins
What is Peristalsis?
Wave-like muscular squeezing in the esophagus, stomach and small intestine
Where is the Sphincter muscle?
Base of esophagus
What is the role of the stomach?
Holds food, mashes and liquefies it
What is chyme?
liquefied food from mechanical and chemical breakdown in stomach
What occurs in the small intestine?
Majority of absorption and segmentation
What occurs in the large intestine/colon?
-Digestion and absorption are nearly finished
-Colon reabsorbs water and minerals
-Fibre and undigested material make up feces
-Rectum stores feces
How long does transit from mouth to rectum take?
1-3 days
What are the 3 chemical aspects in the mouth?
1)Salivary Amylase (breaks down starch)
2)Lingual Lipase (digestion of fat)
3)Salvia helps maintain teeth
Where does protein digestion occur?
Stomach
What does the stomach release for chemical digestion?
Gastric Juice
(Denature proteins and activates pepsin)
How is the digestive tract protected from the acid?
Mucus
Where does most digestion and absorption occur?
Small Intestine
What stimulates the gallbaldder to release bile (emuslifer) into the small intestine?
Hormonal Messengers (CCK stimulated by fat and protein in small intestine)
What is Bile?
Emsuilifer produced in liver and stored in gallbladder released into the small intestine
What is pancreatic juice?
contain enzymes and bicarbonate
-enzymes: digests carbs, protein and fat
-Bicarbonate: neutralizes stomach acid
What does pancreatic and intestinal enzymes break down?
Carbs
Proteins
Fats
What remains the digestive tract?
Water
Fibre
Minerals
What are microbiota?
Refers to the mix of microbial species of a community for example those in the digestive tract
What are probiotics?
Consumable products containing live microorganisms in sufficient numbers to alter the bacterial colonies of the body in ways to believed to benefit health
What are prebiotics?
Substances that may not be digestible by the host such as fibre but serves as food for probiotic bacteria and thus promotes their growth
Where is starch digestion stopped?
pH of the stomach (starts in mouth)
Where are proteins, starch and fat broken down?
Small Intestine
Where are fibres (if possible), fluid and some minerals absorbed?
Large Intestine (colon)
What is small intestine lined with that help absorption?
Villi and Microvilli that increase SA
How is absorption in the intestine selective?
Based on current needs of the body
How does absorption work?
-Nutrients pass through cells of the villi
-Blood and lymph then transport nutrients to the body’s cells
What do blood vessels do in terms of absorption?
Transport most of the products of carbs and protein, vitamins and minerals to the liver
What do lymphatic vessels do in terms of absorption?
Transport products of fat digestion later delivered to bloodstream
How is the digestive system sensitive to poor nutrition?
1) The absorption surface of the small intestine shrinks
2)Without fibre GI tract becomes weak (exercise)
3)Malnutrition itself impairs digestion and becomes self-perpetuating (vicious circle)
What are seven potential problems with digestion?
1)Belching, Gas and Hiccups
2)Heartburn/GERD
3)Choking
4)Dysphagia
5)Constipation
6)Diarrhea
7)Irritable bowel syndrome (IBS)
What is GERD?
Gastroesophageal Reflux Disease: Severe and chronic exposure of the esophagus, throat and mouth, or airway to stomach acids and enzymes causing inflammation and injury
What is Heartburn/GERD?
Reflux of acidic of stomach contents into the esophagus
What is a potential solution for heatburn?
Antacids that neutralize stomach acidity
What are the problems with antacids?
-Produces more acid to restore conditions
-Interfere with ability to absorb nutrients
-Cause indigestion and diarrhea
-Mask the symptoms of an ucler or GERD
What is a Ulcer?
An erosion in layers of cells that from a lining
How is a Ulcer treated?
Antibiotics
What is a Hernia?
A protrusion of a organ or body part through the wall of the body chamber that normally contains the organ.
How are hernias treated?
Surgery
What is choking?
Food is lodged in the trachea and blocks the passage of air
What is Dysphagia?
Difficulty Swallowing
What is Constipation?
Infrequent, difficult bowel movements
What causes constipation?
diet,inactivity,dehydration, medication
How to prevent constipation? x4
1)Defecate when needed
2)Consume Sufficient Fibre
3)Drink Fluids
4)Be physically active
What is Diarrhea?
Frequent bowel movement
What causes diarrhea?
Diet, stress, irritation of the colon
What is IBS (irritable bowel syndrome)
Frequent bouts if diarrhea and constipation
Where does the liver pull waste from?
Blood
What are the two paths waste after the liver processes?
1)Sends them to the digestive tract with bile and to leave the body with feces
2)Prepares them to be sent to the kidneys for disposal in urine
What do kidneys do in terms of the excretory system?
Waste and Water removal
Filter blood and waste and water becomes urine
Where is the excretion or retention of sodium occur? And why is it improtant
Kidney
important for blood pressure regulation
What regulates fluid volume and concentrations of substances in the blood and extracellular fluids?
Kidney
How are kidney function regulated?
Hormones
What occurs when we have extra nutrients?
Store it
How are excess energy-containing nutrients stored?
Glycogen and Fat
How are excess carbohydrates stored?
Glycogen
How are excess fat proteins and carbohydrates stored?
Fat
Where is excess fat stored?
Adipose Tissue
Why are glucose and fat storage systems important?
Ensure that the body cells have a source of energy
What happens to the storage of some nutrients if they reach toxic levels?
Stored without a limit. Vitamin D
What occurs to the storage of nutrients that are usually rapidly depleted?
Stored in small amounts. Vitamin C
