human physiology Flashcards
What is your food’s final destination?
Your cells.
What must the the food do before it gets to the cell?
It must break it down
What are the three phases of nutrition?
- Ingestion
- Digestion
- Egestion
What is ingestion?
Getting the food into the body
What is digestion?
Breaking down food particles to the size of molecules
What is egestion?
getting rid of undigested food
What are the two types of digestion?
- mechanical
2. chemical
What is mechanical digestion?
non chemical breaking down of food
ex: chewing, muscular contractions in the stomach
teeth break food down tongue moves, manipulation.
What is chemical digestion?
uses digestive enzymes to break down the food in ones stomach
What is enzymatic hydrolysis?
Enzymes and water are used to chemically digest food.
What is the chemical formula for the enzymatic hydrolysis?
food+zH20—enzyme—> food fragments
What is intracellular digestion?
takes place inside the cell
ex: Ameba digestion food in its food vacuole or when
the lysosomes merge with food to digest them
What is extra cellular digestion?
food digested outside the cell
ex: our food is digested in the small intestine
The location of the digestion occurring is either….
extracellular or intracellular.
How does food travel to you?
the tongue pushes down the food down the pharynx and to the esophagus
What is peristalsis?
a wave of muscular contractions
What is the peristalsis’ work in the esophagus?
The muscles contract above the bolus and and relax once the bolus pushed down. This happens again and again.
What is reverse peristalsis?
vomit
What is the stomach?
large muscular pouch
What is inside the stomach?
100s of gastric glands, which produce gastric juice
What is gastric juice?
hydrochloric acid and mucus.
What is a gastric ulcer?
caused by too much HCL
What happens after you throw up?
your esophagus burns because the HCL comes up with the food and there is not enough mucus to protect them
What is hunger?
The part of the brain interacting with the amount of sugar in your body.
How is hunger controlled?
It is controlled by your brain.
What is the hypothalamus?
The part of the brain that controls hunger
What is sassation?
The high levels of glucose that stimulate the brain, and you feel “full”.
What happens when you have low levels of glucose?
you feel hungry
What is the salivary duct?
a tube that carries the saliva from the gland to your mouth
What is oral digestion?
It is mechanical, and when you use your teeth to choose your food
What is saliva made of?
Mucin and amylase.
What are the salary glands?
secrete saliva: contains digestive enzymes for carbohydrates
What is pepsin?
an enzyme made by the stomach that breaks down proteins.
How does a protein break down?
protein–> peptide chains—> amino acids
What does mucin do?
lubricates the food. Ex: covers food before you swallow it, and as a result making it easier to swallow
What is amylase?
gastric enzymes used to digest carbs and starch (long chain of glucose) breaks polysaccharides into disaccharides in the mouth.
What are the chemicals in the small intestines?
- peptidase
2. disacchardase
What is the chemical formula for disacchardase?
disacchardase+ H20—disacchardase–> monosaccharides
What are the two parts to the small intestine?
- capillary
2. villi
What is the liver?
largest structure in body- processes and filters blood
bile is produced in the liver
What is the gall bladder?
sack that stores the bile to be secreted to the duodenum
What is bile?
greenish brown fluid for the digestion of fats
What are bile salts?
help lipase digest fats and increase the surface area of the lipids and fats.
What can lipase digest?
lipase can only get to the outer layers of fat, so it helps when salts increase the surface area of the fat
What do Red blood cells do?
transports oxygen throughout the body,
What does the Pancreas do?
produces pancreatic juices and digestive enzymes
sends insulin into the blood
regulates blood sugar and metabolism
What chemicals are in the pancreas?
- Sodium bicarbonate (NaHCO3)
- amylase (has more time)
- Lipase
- trypsin
- Peptidase
- nuclease
What does sodium bicarbonate do?
It neutralized the ph from 2—->8
What is the chemical formula for sodium bicarbonate?
NaHCO3
What is the chemical formula for amylase breaking food down in the mouth?
polysaccharides+H20 —amylase—> disaccarides
What is lipase?
an enzyme that digests fat
What is the chemical formula for fat?
Fat—-> 3 fatty acids +Glycerol
What is the chemical formula for when fat interacts with lipase?
fat+H20—lipase—>3 fatty acids+glycerol
What does trypsin do?
trypsin break down proteins (like pepsin) in the small intestine
What is the ph level that trypsin and lipase works at?
8
What is the chemical formula for peptidase?
peptide chain+H20—-peptidase—>amino acids
What is the chemical formula for nuclease?
nucleic acid+h20—nuclease–> nucleotide
What is the chemical formula to break proteins into peptide chains?
proteins+h20—pepsin—> peptide chains
What do the components of food do for your body?
Give you energy and are useful as building blocks for the body.
Why does the hunger-sassation method not work a 100% on humans?
our hunger is psychological.
What are the phases of digestion?
Oral digestion
Gastric digestion
intestinal digestion
What is the salivary gland?
where the saliva is made
What is the pharynx?
passageway where peristalsis pushes food to the stomach.
What is the esophagus?
passageway where food is swallowed
What is the function of the large intestine?
reabsorbs water and salts to form feces (meets small intestine @ 90 degree angle).
What is the rectum?
temporarily stores and regulates elimination of feces
What is the small intestine?
mixes with chyme and digestive enzymes for final breakdown; absorbs nutrients molecules into the body; secretes digestive hormones into blood.
What is a bolus?
Food down the throat.
What does chewing start the process off?
Oral digestion
How long it take to digest food?
3-4 hours.
What is the mechanical digestion that takes place in the stomach?
Muscle contractions.
What are sphincter muscles?
The muscles that control the passage of waste.
What is the cardiac sphincter muscle?
The sphincter muscle behind the heart that opens into stomach.
What is the pyloric sphincter muscle?
The sphincter muscle that opens into the duodenum of the small intestine from the stomach.
What is the duodenum?
The part of the small intestine immediately from the stomach.
What structure make up the phase of intestinal digestion?
Pancreas, Liver (gallbladder), Small intestine.
What is the pH of the mouth?
About 7
What is the pH of the stomach?
about 2
What is the small intestine’s role?
Chemical digestion.
What are the chemicals in the Small intestine?
- Peptidase
2. Disaccharidase.
What is the formula for trypsin?
proteins+h20—trypsin—> peptide chains
What is the formula for disaccharidase?
disaccharides+h20—disaccharidase—> monosaccharides
How are nutrients absorbed into the body?
Through blood stream.
why are the the folds in the SI there?
to make it easier for the nutrients to get through.
What do bile pigments do?
Color blood red.
What is the caecum?
A habitat for good bacteria.
What is constipation?
When too much water is reabsorbed into the bloodstream by the liver.
What is diarrhea?
When too little water is reabsorbed into the bloodstream by the liver.
How are good bacteria useful?
They eat off your waste and secret vitamins
What is the anus?
The sphincter muscles control the opening and closing
What is feces?
Waste from the body.
What is defecation?
Getting waste out.
What pH does pepsin work at?
It can work at a PH 1.5-2.5.
How long do red blood cells live?
live for 180 days constantly making new ones,
How do the red blood cells die?
old ones die by liver
