Digestion And Healthy Eating Flashcards
How is the small intestine suited to its job?
It is long and thin as well as being folded to increase the surface area, thereby increasing the absorption
These folds are called villi. The cells that make up villi also have small projections called microvilli
What is the singular form of villi?
Vilus
What are held in the pits between the villi?
Secretory glands to secrete mucous and enzymes
How does the food move along the small intestine?
Peristaltic movements that slowly push the food along the tube
What is the purpose of the lacteal?
To transport fat through your lymph system
What is emulsified fat?
It is fat that has been surrounded by bile (a detergent layer)
How is emulsified fat transported?
Hydrophilic outer layer loves water, so is water soluble. The fat will travel through your system until it gets to the liver where it is processed
What is the common bile duct?
The place where the tubes from the gall bladder, liver and pancreas meet. The tube injects bile and pancreatic juice into the first part of your small intestine
What is chyme?
The dissolved foodstuffs that is moving from the stomach to the small intestine
What kind of muscles perform peristalsis?
Circular muscles
Longtitude all muscles
What is digestion?
The process whereby food is broken down- by mechanical and chemical means- into water soluble molecules so that they can be used to create nutrients that can be assimilated into the blood stream
What is mechanical digestion?
When food is churned or squashed in order to break it down
What are examples of mechanical digestion?
Chewing in the mouth
Cheeks hold the food in place
Churning in the stomach (to mix the food)
Peristalsis- oesophagus/intestine (to move the food)
What is peristalsis?
When muscles contract and expand to push food down a tube
What is chemical digestion?
When the chemical composition of food is changed to break it down
What are examples of chemical digestion?
Enzymes in saliva
Hydrochloric acid in stomach
Enzymes are proteins made by amino acids
What is amylase?
The enzyme that breaks down starch
What is starch?
Amylose
Carbohydrates
What are the eleven organs of digestion?
Oral cavity Pancreas Large intestine Appendix Oesophagus Liver Stomach Gall bladder Small intestine Rectum Anus
What is the pharynx?
The valve that is between the oesophagus and windpipe
What does the pharynx do?
It prevents food from going down the windpipe
What is a bolus?
A ball of food that is pushed down the oesophagus into the stomach
What is in the oral cavity?
Teeth
Salivary glands
Tongue
What do the teeth do?
They grind food
What does the tongue do?
It pushes food underneath the teeth Forms a bolus Pushes the bolus down the throat Tastes the food Cleans teeth
What kind of digestion happens in the oral cavity?
Mostly mechanical Some chemical (amylase)
What happens in the oral cavity?
Moisture is added to the food
What are the three salivary glands?
Parotid gland
Sublingual
Submandibular
What does the pancreas do?
Secretes:
Hormones
Digestive enzymes
What do the hormones-secreted by the pancreas- do?
Control blood sugar levels
What does the large intestine do?
Extracts moisture and any nutrients that are left after the food has passed through the small intestine
Absorbs vitamin k
What does the appendix do?
Nobody knows…
What does the oesophagus do?
Tube that pushes food from the mouth to the stomach
How does the oesophagus move the bolus from the mouth to the stomach?
Through peristalsis
What does the liver do?
Secretes bile and digestive enzymes
Bile helps to emulsify fats
Liver is responsible for filtering toxins from the bloodstream
What does the stomach do?
Mixes food with hydrochloric acid
Hydrochloric acid breaks down proteins
Stomach churns the food
What kind of digestion happens in the stomach?
Mechanical-churning
Chemical-acid
What does the gall bladder do?
Stores the bile and enzymes that are secreted by the liver
It will release this mixture when it is needed by the stomach
What does the small intestine do?
It is responsible for digestion
Absorbs nutrients, lipids and other useful substances
Sends necessary substances to be assimilated into the bloodstream
What does the rectum do?
Stores waste products (faeces that need to be removed)
What does the anus do?
Expels waste products
What is the function of saliva?
Contains enzymes that help to break down food
Help to make food water soluble
Lubricates the mouth-helps with swallowing and chewing
How does emulsify fats?
Surrounds the fat molecule with a “detergent”
The outer layer of the bile is hydrophilic -likes to be in water
This enables fat to be assimilated into the bloodstream
What is the cecum?
The part of the large intestine that connects to the small intestine
What is the colon?
Another name for the large intestine