The Digestive System

Question 1

digestion

Answer 1

the breakdown of large insoluble molecules into small soluble molecules by chemical and physical means

Question 2

an/o

Answer 2

anus

Question 3

append/o

Answer 3

appendix

Question 4

appendic/o

Answer 4

appendix

Question 5

cholecyst/o

Answer 5

gall bladder

Question 6

col/o

Answer 6

colon

Question 7

colon/o

Answer 7

colon

Question 8

or/o

Answer 8

mouth

Question 9

stomat/o

Answer 9

mouth

Question 10

enter/o

Answer 10

intestines (normally small)

Question 11

duoden/o

Answer 11

duodenum

Question 12

esophag/o

Answer 12

oesophagus

Question 13

gastr/o

Answer 13

stomach

Question 14

hepat/o

Answer 14

liver

Question 15

ile/o

Answer 15

ileum

Question 16

jejun/o

Answer 16

jejunum

Question 17

pancreat/o

Answer 17

pancreas

Question 18

proct/o

Answer 18

anus and rectum

Question 19

rect/o

Answer 19

rectum

Question 20

sigmoid/o

Answer 20

sigmoid colon

Question 21

processes of digestion - ingestion

Answer 21

mouth - mechanical (mastication) and chemical (enzymes) breakdown

Question 22

processes of digestion - propulsion

Answer 22

oesophagus - movement of bolus/peristalsis

Question 23

processes of digestion - digestion

Answer 23

stomach, duodenum - chemical (gastric juice) and mechanical (churning) breakdown

Question 24

processes of digestion - absorption

Answer 24

jejunum, ileum - absorption of nutrients into cardiovascular system

Question 25

processes of digestion - assimilation

Answer 25

small intestine - digested food products are converted into fluid and solid parts of a cell/tissue

Question 26

processes of digestion - elimination

Answer 26

large intestine, rectum, anus - undigested food residues are egested from the body as semi-solid faeces

Question 27

mouth

Answer 27

function = point of entry, commence ingestion for the digestive system

includes mechanical (teeth/tongue for chewing) and chemical (salivary glands/saliva) breakdown

Question 28

teeth

Answer 28

tearing/grinding/cutting/breaking down food into small enough portions to swallow

maintain good oral health by having regular dental check-ups, daily tooth brushing and flossing, fluoride in water helps to strengthen enamel

Question 29

tongue

Answer 29

chewing/mastication of food (moves food to between teeth), swallowing, speech and taste

Question 30

salivary glands

Answer 30

includes parotid, submandibular, sublingual

function = produce saliva, lubricate food, chemical digestion, taste, cleaning of the mouth

Question 31

oesophagus

Answer 31

long tube approx. 25cm long and 2cm wide, posterior to trachea

function = carry food from the pharynx to the stomach via peristalsis

Question 32

stomach - structure

Answer 32

muscular bag - 3 layers - longitudinal (outer), circular (middle), oblique (innermost)

sphincter - ring like muscles surrounding and able to contract/close a passage or opening

           - oesophageal
           - pyloric (between stomach and duodenum)

Question 33

stomach - function

Answer 33

mechanical - contraction = churn food, secrete mucous = lubrication

chemical - create and secrete pepsin (break down protein)

protective - HCl = kill invading pathogens and stops action of salivary amylase

Question 34

small intestine - adaptations

Answer 34

single wall of columnar epithelial cells = short diffusion pathway

villi and microvilli = increase surface area of intestines for absorption

Question 35

small intestine - duodenum

Answer 35

• first part of small intestine to leave stomach
• final stage of digestion
• gall bladder and pancreatic secretions merge at this point of the structure

Question 36

small intestine - jejunum

Answer 36

• roughly 2m long, middle section of small intestines
• absorb nutrients
• villi + microvilli line walls

absorb:
proteins
carbs
vitamins
minerals
lipids

Question 37

small intestine - ileum

Answer 37

• end section, walls lined by villi and microvilli
• ileocecal valve = conjunction of small and large intestines to stop back flow of contents up alimentary tract
• absorb nutrients

absorb:
water
bile salts
vitamin B12
lipids

Question 38

pancreas

Answer 38

-abdominal organ, posterior to stomach, connected to duodenum by pancreatic duct

function:
pancreatic juice containing amylase (starch), trypsin (protein), lipase (lipids), nucleases (nucleic acids) and sodium hydrogencarbonate (neutralize acidic chyme)

regulate BGL - insulin respond to high, glucagon respond to low

Question 39

liver

Answer 39

largest gland in body

function = metabolism of carbs/fats/proteins, production and secretion of bile

Question 40

bile

Answer 40

composed of water/mucous/mineral salts/bile pigments (bilirubin - left over RBC)/bile salts/cholesterol

function = digest insoluble fatty acids - break down into smaller droplets

stored and concentrated by the gall bladder

Question 41

absorption

Answer 41

the movement of digested food molecules and nutrients across the intestine wall into the blood or lymph

Question 42

application - coeliac disease

Answer 42

autoimmune disease triggered by gluten = damage to small intestine

villous atrophy = inflammation and flattening of the villi therefore decreased absorption of nutrients

Question 43

large intestines

Answer 43

consist of:
caecum
ascending/transverse/descending colon
sigmoid colon, rectum

receives indigestible food (fibre)

absorbs remaining water and electrolytes

Question 44

faeces

Answer 44

composed of 60-70% water, fibre, dead/live microbes, epithelial cells from gut lining, fatty acids, mucous

formation:

1) undigested food (chyme) enters colon from ileum
2) water, salts, vitamins are reabsorbed
3) dehydration and compaction
4) semi-solid faeces/stool

Question 45

rectum and anus

Answer 45

rectum: starts at sigmoid colon, terminates in the anal canal
anus: leads from rectum to the exterior of the body via an external sphincter (skeletal muscle - voluntary)

Question 46

maintaining a healthy digestive system

Answer 46

healthy diet - fibre and water intake is adequate

regular exercise - aerobic exercise speeds up breathing and heart rate, stimulating the natural squeezing of muscles in the intestines

hygiene - prevent pathogens from remaining or reentering e.g. washing hands after using toilets