unit 4- The Digestive System Flashcards
Where does the digestive system begin?
What is the digestive system?
It is a long tube that begins at the mouth and ends at the anus.
Where do we first put our food when eating?
In our mouth, also known as the buccal cavity.
What is the buccal cavity?
Our mouth.
Where does saliva come from?
Salivary glands
What is the role of the saliva?
It helps to moisten the food, making it easier to swallow, as it helps to break down the food.
Where are the saliva glands located?
Under the tongue and in the cheeks.
When we swallow food, where does it pass before travelling down the oesophagus?
The epiglottis
What is the oesophagus?
A muscular tube that allows the broken down food to enter the stomach.
It is squeezed by muscles.
What is the action called where food is squeezed down the oesophagus by muscles?
Peristalsis
What is the stomach?
A muscular sack which churns our food around and starts to chemically alter the protein in our diet.
Where will food enter once chemically altered in the stomach?
The small intestines.
Wil food still be chemically altered in the small intestines?
Yes
What fluid chemically alters our diet in the small intestines?
Bile
Where is bile produced?
In the liver
Where is bile stored?
Gallbladder
Where’s the second location that altered foods will pass through when in the small intestines?
The food will pass into a further region called the ileum.
What is the ileum covered with?
small finger like projections called villi
What is villi?
They are small finger like projections that cover the ileum which contain blood vessels.
Once the nutrients are small enough they can be picked up by the blood to be used in the body.
What is left in the small intestines after the blood vessels in the villi have collected the nutrients?
water and food substances that we are unable to break down.
Where will water and food substances that we are unable to break down in the small intestines move to?
The large intestines where most of the water will be taken back into the blood.
Where’s the dried out remains of our food and dead bacteria faeces stored?
In the rectum
Where will waste eventually be expeled from?
The anus
What is the anus?
A muscular tub that will expel waste from.
What substance changes food into forms that can be absorbed by the blood in our digestive system?
Enzymes
What is enzymes changing our foods into forms that can be dissolved into our blood called?
Chemical digestion
What is chemical digestion?
When enzymes change food into forms that can be dissolved into our blood, used by the body.
What is mechanical digestion?
It starts when we chew food, making it small enough to swallow.
Most takes place in the stomach when muscles in the wall churn our food around, breaking it into small pieces.
What do we see when we throw up?
Chyme
What is chyme?
The fluid we see when we vomit, which helps us to break food into small pieces.
What enzyme breaks down starch?
Amylase
What does starch turn to when it is broken down?
Maltose
What is the enzyme that breaks down fats?
Lipase
What do fats turn into when broken down?
Fatty acids and glycerol
What does the chemical change of food start by in the mouth?
Saliva
What is the adaptation of the villi for effective use?
The villi of the ileum wall increases the surface area so that many nutrients as possible are absorbed.
What does each villi contain?
Blood capillaries and a central vessel called the lacteal.
What is the lacteal in a villi connected to?
The lymphatic system
Where will products of digestion go after entering the blood?
They will enter the blood and will travel along the hepatic portal vein which carries them to the liver.
This is instead of taken around the body to the heart.
How many functions does the liver carry out?
over 500 different functions
What are the digestive malfunctions?
IBS
gallstones
Coeliac disease
What does IBS stand for?
irritable bowel syndrome
What is the cause of irritable bowel syndrome?
When the muscles of the gut alter their normal rhythms.
What are the symptoms of irritable bowel syndrome?
alternating bouts of constipation and diarrhoea
abdominal pain
bloating
indigestion
What are contributing factors to IBS?
stress
dietary triggers such as alcohol, caffeine, fried food and chocolate.
What are the treatments for IBS?
Cook homemade meals which are less fatty.
Exercise more frequently
Try different medications for diarrhoea or constipation.
What is the type of medicine used to treat diarrhoea?
imodium
What is the type of medicine used to treat constipation?
laxitives
What tests will the doctors do to investigate whether you have IBS?
Blood tests
Take a sample of poo to check it for any infections
Where do gallstones form?
In the gallbladder
Why do gallstones form?
Due to an imbalance in the composition of bile.
How do gallstones form?
High levels of cholesterol and bilirubin result in the formation of crystals that grow to form gallstones.
They stick to the bile ducts and cause pain and discomfort.
How big can gallstones range in size?
From specks to pebbles
What are the symptoms of gallstones?
severe abdominal pain
loss of appetite
jaundice
When is abdominal pain the mot severe for gallstones?
When bile is released after a fatty meal.
What are the risk factors of gallstones?
being female
overweight
IBS
over 40 years old
What are the treatments for gallstones?
Key hole surgery to remove the gallbladder.
Medicines
Lithotripsy- a laser that dissolves the gallstones.
What is a lithotripsy?
Helps to treat gallstones by using high frequency sound waves to vibrate apart solid objects like gallstones.
What type of disease is coeliac disease?
An autoimmune disease
How is coeliac disease an autoimmune disease?
A protein from wheat called gluten triggers an immune response which results in the villi of the ileum wall being destroyed.
What foods can we find gluten in?
Pasta
bread
cakes
What are the symptoms of coeliac disease?
abdominal pain
bloating
diarrhoea
and weight loss due to the poor absorption of nutrients
Why is there a poor absorption of nutrients for coeliac disease?
as the villi becomes flattened so reduced absorption
What is the treatment for coeliac disease?
Exclude foods that contain gluten in your diet.
