Digestion, Nutrition & Obesity

Question 1

What is a nutrient?

Answer 1

substance in food that are used to promote normal, growth, maintenance and repair (metabolised for building blocks or energy)

Question 2

What are the uses of carbohydrates in the body?

Answer 2

Glucose (monosaccharide) = fuel

Question 3

What can happen if you have excess carbohydrates in the body?

Answer 3

• depressed brain function and neurone death
• obesity
• diabetes mellitus
• dental cares
• gastrointestinal irritation
• excess glucose converted to fat and glycogen

Question 4

What can happen if you have deficient carbohydrates in the body?

Answer 4

• tissue wasting
• metabolic acidosis

Question 5

What are the uses of lipids in the body?

Answer 5

• provides protection for organs
• integral part of myelin sheaths
• cholesterol used in plasma membranes
• major energy fuel of skeletal muscle

Question 6

What can happen if you have deficient lipids in the body?

Answer 6

• weight loss
• problems controlling heat
• poor growth, skin lesions

Question 7

What can happen if you have excess lipids in the body?

Answer 7

• obesity
• increased risk of cardiovascular disease
• atherosclerosis

Question 8

What are the uses of proteins in the body?

Answer 8

• tissue maintenance and growth
• rate protein synthesis = breakdown
• positive nitrogen balance needed needed for pregnant women or growing children
• negative nitrogen balance (seen in physical and emotional stress)

Question 9

What can happen if you have deficient proteins in the body?

Answer 9

• profound weight loss
• tissue wasting
• anaemia
• oedema

Question 10

What can happen if you have excess proteins in the body?

Answer 10

• obesity
• enhanced calcium excretion
• bone loss

Question 11

What are vitamins?

Answer 11

organic compounds needed for growth and good health

Question 12

What are electrolytes?

Answer 12

chemicals that regulate nerve and muscle function, hydrate the body, balance blood acidity and pressure, and help rebuild damaged tissue

Question 13

What are some examples of electrolytes?

Answer 13

• Sodium
• Potassium
• Calcium
• Bicarbonate
• Magnesium
• Chlorine
• Phosphate

Question 14

What is anabolism?

Answer 14

reactions that build larger molecules and structures

Question 15

What is catabolism?

Answer 15

process of breaking down, complex structures into simpler ones

Question 16

What is oxidation?

Answer 16

food molecules react with oxygen present in our body causing formation of water and carbon dioxide and release of energy

Question 17

What are the short term controls of food intake?

Answer 17

• Vagus nerve
• nutrient signals
• gut hormones

Question 18

What are the long-term controls of food intake?

Answer 18

• insulin
• leptin

Question 19

What is basal metabolic rate (BMR)?

Answer 19

Energy of cost of living
- reflects the need to maintain essential activities like breathing and maintaining organ function
- controlled by thyroxine hormone

Question 20

What is metabolic rate?

Answer 20

kilocalorie consumption required to fuel all ongoing activities

Question 21

What does the digestive system consist of?

Answer 21

• Mouth
• Oesophagus
• Stomach
• Liver
• Gall bladder
• Pancreas
• Small intestine – duodenum, jejunum and ileum
• Large intestine
• Anus

Question 22

What are the major processes occurring in the digestive system?

Answer 22

• Ingestion
• Secretion
• Mixing and Propulsion
• Digestion
• Absorption
• Defecation

Question 23

What are the (3) mouth functions?

Answer 23

• ingest food
• masticate (chewing)
• mix food with saliva

Question 24

What are the (3) functions of the salivary glands?

Answer 24

• cleanses mouth
• dissolves food chemicals to facilitate taste
• moistens food to enable bolus formation

Question 25

What are the 2 phases of deglutition (swallowing)?

Answer 25

• Buccal phase – bolus formation
• Pharyngeal-oesophageal phase – tongue blocks mouth, epiglottis closes and upper oesophageal sphincter relaxes to allow food into oesophagus

Question 26

What (2) muscles help push food into the oesophagus?

Answer 26

• oropharynx
• laryngopharynx

Question 27

What does the epiglottis do?

Answer 27

closes to prevent food going into the trachea and direct it to the oesophagus

Question 28

How does the oesophagus connect to the stomach?

Answer 28

via the oesophageal hiatus and the cardiac sphincter

Question 29

What is propulsion?

Answer 29

peristalsis pushes food to fundus

Question 30

What is grinding?

Answer 30

vigorous mixing motion close to pylorus

Question 31

What is retropulsion?

Answer 31

pylorus forced back to the stomach