LO3

Question 1

Order of digestion structure

Answer 1

Mouth, salivary glands, oesophagus, stomach, pancreas, liver, gall bladder, small intestine, large intestine, rectum.

Question 2

Order of digestion.

Answer 2

Food into our buccal cavity: grind food down using our jaw, teeth and tongue: saliva rom salivary gland helps moisten the food and make it easier to swallow: food slides past the epiglottis and enter the oesophagus: this is a muscular tube which squeezes food using muscles (peristalsis).

Stomach is a muscular sack that churns our food, starts to chemically alter protein in our diet: after food leaves our stomach (chyme), enters the small intestine (duodenum) chemical alteration takes place aided by fluids fro liver and pancreas: bile made by the liver and stored in the gallbladder, passes down to the bile duct to the gut.

Altered nutrients pass into further regions of the small intestine (ileum): covered in villi, contain blood vessels: nutrients are small enough to be collected by bloodstream.

Water and food substances we can’t breakdown remain in the gut: move into large intestine or colon

Dried out remains of food and dead bacteria form faeces: stored in rectum: muscular tube eventually gets rid of waste through anus.

Question 3

Mechanical and chemical digestion

Answer 3

Nutrients from food have to be changed into forms that can be absorbed by the blood or dissolve in water of plasma.

Enzymes are used to chemically change nutrients into smaller, soluble units: chemical digestion.

Food must be small enough for enzyme molecules to get at the nutrients, food must be physically broken down: mechanical digestion.

Question 4

Mechanical digestion

Answer 4

Chewing action: teeth breakdown large pieces of food into smaller ones that can be swallowed

Stomach: churns food to break it down.

Small intestine: bile emulsifies lipids: helps with mechanical digestion of fats

Question 5

Chemical digestion

Answer 5

Nutrients are broken down by enzymes into smaller molecules that can be absorbed into the blood and used by cells.

Buccal cavity: food is dissolved by saliva: contains salivary amylase

Stomach: chemical reaction stops because low ph causes acidic environment (hydrochloride acid denatures enzyme)

Stomach acidity cause chyme to have a lower PH: which prevents other chemical digestions due to denaturing of enzyme: chyme must be neutralised by bile from pancreatic juices.

Pancreas and walls of duodenum: supply more digestive enzymes.

Question 6

Absorption: adaptation of intestine wall

Answer 6

• absorption: how nutrients from food are absorbed into the bloodstream: occurs in small intestine
• villi and microvilli increase surface area: enable efficient absorption
• villi contain blood vessels and lacteals
• nutrients enter by diffusion

Question 7

Role of liver in assimilation

Answer 7

• assimilation is the movement of digested food molecules into cells of body where they are used up
• excess glucose in blood reaching the liver, converts glucose into glycogen, to be stored for respiration
• the liver is where toxins such as alcohol are broken down.

Question 8

IBS symptoms

Answer 8

• stomach pain and cramping
• change in bowel habits, diarrhoea or constipation
• bloating and swelling of the stomach
• Excessive wind
• sudden need to go to the toilet
• mucus passing through anus

Question 9

IBS biological explanation

Answer 9

• IBS causes food to move slower or faster through the digestive system: if it moves to quickly, causes diarrhoea because not enough water is getting absorbed: if it moves slowly, causes constipation because too much water is absorbed, makes faces hard.

Question 10

IBS causes

Answer 10

• linked to increased sensitivity of gut to certain food
• related to problem of digesting food
• triggered by something a person ate or drank

Question 11

Coeliac disease symptoms

Answer 11

• indigestion, stomach pain, bloating, diarrhoea or constipation, anaemia
• feeling tired all the time as a result of malnutrition
• children not growing at expected rate, adults experiencing unexpected weight loss

Question 12

Coeliac disease biological explanation

Answer 12

• autoimmune condition: immune system mistakes parts of body as foreign and attacks it
• immune system mistakes gliadin, substance found in gluten, as a threat and attacks it.
• this causes damage to villi: become flattened: body’s absorption of food and nutrients is distrusted

Question 13

Coeliac disease causes

Answer 13

• runs in the family
• associated with genetic mutations: responsible for development of immune system
• introducing gluten before the age of 6 months can increase risk of developing coeliac disease

Question 14

Gallstone symptoms

Answer 14

• abdominal pain
• excessive sweating, feeling sick or vomiting
• jaundice: yellowing of skin and whites of eyes
• itchy skin, diarrhoea
• loss of appetite

Question 15

Gallstone biological explanation

Answer 15

Gallstones can form if:
- high levels of cholesterol inside gallbladder
- high levels of waste products inside gall bladder

Chemical imbalances cause tiny crystals to develop in bile: gradually grow into solid stones

Question 16

Gall stone causes

Answer 16

• caused by imbalance of chemicals
• most common in people who are overweight or obese, in people aged over 40, have a condition that affects Bile

Question 17

Monitoring digestive malfunctions

Answer 17

Ultrasounds: can examine liver and other organs below abdomen and pelvis. Lubricating gel is used on skin, to allow smooth movements of small hand-held probe. Sound waves bounce back offf the body tissues and forms an image on a monitor screen.

Gastroscopy: uses an endoscope- examines oesophagus, stomach and duodenum. Procedure uses a long, flexible tube called endoscope. It’s inserted into body through mouth or anus.

Cholangiography: can give further information about the condition of gallbladder. Uses dye that shows up on x-rays. Dye may be injected into the bloodstream or directly into bile duct. Can help detect abnormalities.

Question 18

Treatment for IBS

Answer 18

To avoid diarrhoea:
- cut down on high-fibre foods, like wholegrain foods (such as
brown bread and brown rice), nuts and seeds
- avoid products containing a sweetener called sorbitol.
To avoid bloating, cramps, flatulence:
- avoid foods that are hard to digest, such as cabbage, broccoli,
cauliflower, beans, onions and dried fruit
- eat up to 1 tablespoon of linseeds a day.

Question 19

Treatment for coeliac disease

Answer 19

• Give up all foods containing gluten for life to avoid long-term damage
  to health.
• Vaccinations, e.g. flu jab, as individuals with coeliac disease are more
  vulnerable to infection.
• Vitamin and mineral supplements can also help correct any dietary
  deficiencies.

Question 20

Treatment for gallstones

Answer 20

• treatment depends on how symptoms are affecting the individuals daily life.
• for someone who doesn’t have symptoms: active monitoring: individual doesn’t receive immediate treatment: if individual gains symptoms: call GP.
• sometimes removal of gallbladder
• medication: tablets to dissolve small gallstones( aren’t very effective, taken for a long period of time, gallstones can recur once treatment stops)
  -lithotripsy is a non-surgical treatment: endoscope is used to deliver shock waves and shatter gallstone

Question 21

Impact on diet and lifestyle: IBS

Answer 21

• Abdominal pain and discomfort from bloating may restrict sleep,
  leading to tiredness and emotional frustration.
• The need to visit the toilet may restrict trips out and socialising.
• Flatulence may be embarrassing and reduce confidence when
  socialising with others.
• Can restrict diet and may make socialising difficult and embarrassing
  as the individual may not be able to eat or drink the same as friends.
• Coffee and fizzy drinks can cause irritation in the gut, so need to be
  avoided.
• May need to avoid stressful situations - this is not always easy.
• Keep a food diary to identify foods that cäuse irritation or pain.
• Take regular exercise - this can relieve stress and increase feelings of
  wellbeing.

Question 22

Impact on diet and lifestyle: coeliac disease

Answer 22

• Remove gluten from the diet by excluding wheat products, otherwise
  villi will be damaged.
• Take additional vitamin and mineral supplements - may be a
  deficiency until villi regrow, due to impaired absorption.
• Read food labels very carefully when shopping as flour is often used as
  a thickening agent.
• Take care when eating out - look for gluten-free products. Most items
  on menus are likely to contain gluten.
• Take care when eating at the homes of family and friends (as above).
  Avoid using oil that has been used to fry gluten - may be traces of
  products containing gluten, e.g. batter.

Question 23

Impact on diet and lifestyle: gallstones

Answer 23

-The gallbladder is not an essential organ and so individuals can lead a
normal life without one.

• After surgery to remove the gallbladder some people may experience
  symptoms of bloating and diarrhoea after eating fatty or spicy food. It
  is recommended to avoid those types of food.
• It is recommended to eat a healthy and balanced diet based on the
  Eatwell Guide. This involves eating a variety of foods - including
  moderate amounts of fat - and having regular meals.