unit 4 Flashcards
organ systems
3 main compartments in the body that store food
- cytoplasm inside cells
- fluid between cells (interstitial fluid)
- fluid in the blood
macromolecules are in 4 major groups
- carbohydrates
- lipids
- proteins
- nucleic acids
all 4 together are called essential nutrients
carbohydrates
- Monomer: monosacerides
- CHO
- gets digested in the mouth
lipids
- monomer: fatty acids and gycogen
- CHO
- gets absorbed in small intestine
proteins
- monomer: amino acids
- CHON
- gets absorbed in the stomach
nucleic acids
- monomer: nucelotides
- CHONP
- gets absorbed in the small intestine
4 stages of food processing
- indigestion
–> take in or eating of food - digestion
–> breakdown of food by mechanical or chemical processes into small molecules for body to absorb - absorbtion
–> transporting productions of digestion into circulatory system, distributing to body - elimination (egestion)
–> removal of undigested solid waste from body
alimentary canal
- a tube that has a mouth at one end to ingest food and an anus in the other end to excrete waste
- along this tube - different organs will process food differently
mechanical digestion vs chemical digestion
mechanical:
- the physical breakdown of large pieces of food into small pieces
- mouth by action of teeth
- contractions
chemical digestion:
- chemical breakdown of nutrient molecules into small molecules by enzymes
amylase
- enzyme that breaks down starches in food into simple sugars
- dissolves water-soluble food particles
- stimulates taste buds to allow us to taste flavour in foods
- lubricates food to make food easier to swallow
upper part of digestive system
- starts with the mouth
- salivary glands are triggered by the smell or sight of food
- the glands in the mouth produce saliva to begin the chemical digestion of food
- mechanical - is when you bite and grind food
- the smaller pieces increase surface area of food and allow more exposure for saliva to chemically digest it
the esophagus
- when chewing ur tonge shapes food into a bolus and pushes in to back of the mouth
- bolus moves to esophagus
- the epiglottis is the cartilage valve that closes the trachea during the swallowing motion
- bolus is transported through esophagus, a muscular tube that connects the mouth to the stomach by peristalsis
- the esophageal sphincter is the transition between esophagus and stomach which allows bolus to enter the stomach (prevents heatburn and acid reflex) (closed to prevents stomach acid from backing up)
stomach
- stores food temporaily and helps with mechanical and chemical digestion
- the lining of the stomach secretes gastric acid (made of HCL and chemicaly digests food)
- stomach is coated with mucous that prevents damage from PH in acid
- micture of food and gastric juice produces chyme
- chyme leaves stomach through pyloric sphincter to small intestine
duodenum
- first part of the small intestine
- area for absorbing nutrients because the walls are covered in villi
- each villi is covered by microvilli
- acessory organs all support digestion in this area (pancreas and gallbladder)
jejunum and ileum
Jejunum:
- right after the duodennum
- breaks down proteins and carbohydrates to enter the blood stream
Ileum:
- after jejunum
- contains smaller villi than the other two sections
- absorbs nutrients and pushes undigested material to the large intestine
Large intestine
also known as colon
- absorbs any of the water in the food and leaves the undigested matter
- the leftover matter forms feces and is pushed by contractions to the rectum
Bilirubin
makes the brown colour in feces
- by production of breakdown of hemoglobin
accessory organs
pancreas:
- secretes pancreatic fluid that contains enzymes
- changes the pH of chyme to pH 1 to pH 8
- produces insulin and digestive juices and hormones to do with digestion
Liver
- filters blood and produces bile that helps with digestion and carry away waste
galbaldder
- stores bile
digestive system disorders
PEPTIC ULCERS
- abdominal pain, bloating, nausea, loss of appetite
- sore in the lining of the stomach or duodenum where hydrochloric acid and pepsin are present
- they form when the tissues become inflamed because the protective mucus that covers the lining has weakened
INFLAMMATORY BOWEL DISEASE
- group of diseases that cause inflammation in the intestines
CROHNS DISEASE
- inflammatory disease that can affect any part of the alimentary canal from the mouth to anus
ULCERATIVE COLITIS
- a form of inflammatory disease that attacks the colon
HEPATITIS
- inflammation of the liver most commonly caused by a virus
- caused by contact
CIRRHOSIS
- the irreversible replacement of healthy liver tissue with non-functioning scar tissue, most commonly caused by excessive alcohol intake or hepatitis
Diabetes
- a condition in which the body is unable to use glucose for energy
tidal volume, inspiratory reserve volume, expiratory reserve volume
TIDAL
- volume of air inhaled when body is at rest
INSPIRATORY
- additional volume that can be taken inro lungs beyon tidal inhalation
EXPIRATORY
- additional volume of air that can be forced out of lungs beyond tidal exhalation
vital capacity (total lung capacity) vs residual volume
VITAL CAPACITY
- total volume of gas that can be moved in or out of the lungs
= tidal volume + inspiratory reserve + expiratory
RESIDUAL
- amount that gas that gas stays in lungs after full exhalation
- gas never leaves the system
2 requirements
- the respiratory surface (where gas exchange occurs) must be large enough for gasses to exchange quickly
- respiration must take place in a moist environment (o2 and CO2 needs to be dissolved in water)
type of respiratory surfaces in animals
- OUTER SKIN
- for animals that dont have specialized gas exchange organs
- O2 diffuses into thin-walled capillaries just below the skin as CO2 diffuses out
- need to live in damp places - GILLS
- extensions or folds in body surface that increases the surface area as O2 from water diffuses across gill surfaces into capillaries as CO2 diffuses out - tracheal system
- insects exchange
- internal system of branching respiratory tubes
- directly connected from body cells to environment
- O2 enters and diffused into trachea while CO2 does opposite - lungs
- land animals
inspiration vs expiration
INSPIRATION
- the action of drawing oxygen-rich air into the lungs (inhaling)
EXPIRATION
- the action of releasing waste air from the lungs (exhaling)