UNIT D1 FLASHCARDS: Digestion, Respiration, Muscle
Peristalsis
The movement
of food through
the entire
digestive tract is
achieved
through the
rhythmic
contractions of
muscle lining the
entire alimentary
canal.
Digestion
The chemical breakdown of organic molecules into smaller
complexes.
Absorption
The movement of digested nutrients to the tissues of the body
Alimentary canal
The digestive tract. An open-ended muscular tube that
measures between 6.5 – 9 meters in length. includes stomach, small and large intestine.
Mastication
-Chewing reduces the size of food particles and increases
the surface area.
-This chewed paste is called a bolus.
Saliva
-A combination of water, mucin and amylase
-Secreted by the salivary glands (pH of 6.4).
-This activates taste buds and lubricates the passage of food.
Amylase
- An enzyme that breaks down starch into dextrin (6 – 8
glucose units) and maltose (2 glucose units).
Cardiac sphincter
-Regulates the movement of food from the esophagus
into the stomach. open and closing door for food to enter stomach from esophagus.
Pyloric sphincter
-Regulates the passage of food from the stomach into
the duodenum. open and closing door for food to enter small intestine from stomach.
Pepsinogen
-The active enzyme for pepsinogen is pepsin.
-Pepsin degrades protiens in to small parts called peptides.
HCl
-An acid secreted by the parietal cells as H+ and Cl- and
acts as an acid only when combined in the stomach cavity
(lumen).
-This activates Pepsinogen and helps break protein
hydrogen bonds.
Rennin (chymosin)
-An enzyme that coagulates
milk so that we can properly digest the milk in a curdeled form
-prodcued only in infants
Mucin
-A bicarbonate rich watery
substance containing
glycoproteins.
-This protects the stomach
lining from digestion!
Hormones
Proteins that enter the blood stream and trigger the
actions of other body structures
Gastrin
-A hormone triggered by the presence of proteins in the
stomach and stomach distension (filling).
-It targets the stomach wall and causes the release of
gastric secretions.
The Pancreas
An organ connected to
the duodenum by the
pancreatic duct. The
secretion of enzymes that
help digest chyme (partly digested food).
The Liver
A large organ that detoxifies
chemicals, breaks down old
red blood cells and produces
bile. An emulsifier that helps to
increase the surface area of
lipids. This does not
chemically digest lipids
The Gallbladder
a small muscular sac that
stores biletha was produced by liver. The gallbladder
empties bile into the
common bile duct. the common blie duct leads to the doudenum.
The Small Intestine
The
absorption of all chemically
digested foods:
Monosaccharides, amino
acids and triglycerides.
An organ located between
the stomach and the large
intestine.
Glucose and Amino
Acids
Actively transport across
the intestinal wall into the
bloodstream.
Glycerol and fatty
acids
Passively diffused into the
lymph vessels for
eventual transport into
the bloodstream.
The Large Intestine (colon)
Water
absorption,
Waste storage
Storage of
bacteria
Production of
some vitamins
Complex carbohydrates
long chains of glucose that are
linear and branched (starch) or
only branched (glycogen-
stored form of glucose in
animals)
Cellulose
A complex plant carbohydrate composed of
glucose subunits. Humans cannot break the
glucose to glucose bonds. The enzyme
cellulase is required.
Proteins
long chains of amino
acids
Polypeptides
medium lengths of amino acids, aka smaller protiens
Amino acids
single molecule
units containing nitrogen.
Lipids
fatty acids joined to
glycerol
Bile
comes from the liver, is stored in the gallbladder. aid digestion in fats
Lipases
enzymes that chemically
breakdown lipids into glycerol and 3
fatty acids madein salivary glands and stomach.
Protein Structure
Primary structures are held together by peptide bonds.
Secondary structures form sheets or helixs held together by
hydrogen bonds.
Tertiary structures are held together by hydrogen, sulphur or
other non-covalent bonds
Quaternary structures are also held together by hydrogen,
sulphurs or other non-covalent bonds.
Respiration
The process by which O2
is supplied to cells
and CO2
is removed from cells.
Breathing
- Bones and muscles, controlled by nerves,
bringing large volumes of O2
rich air into the
lungs and remove CO2
rich air from the lungs.
Diffusion
- Lungs provide a thin surface of tissue through
which O2 and CO2 can pass. - This process is defined as a gas exchange.
Pharynx
- A passage for both food and air
Larynx
- The voice box (Adam’s apple)
that opens to let air pass into the
trachea.
Trachea
- The ‘windpipe’ held open by rings of
cartilage. - The epiglottis prevents food from
passing down.
Bronchi (plural)
- The trachea branches into 2 tubes
called bronchus tubes.
Lungs
- Expandable organs in the chest cavity.
- The site where gas exchange takes
place.
Pleural Membrane
- Thin membranes lining the ribcage
and lungs. - The pleural space between
membranes contains fluids to
reduce friction. - This space also produces a suction
that pulls helps to expand the lungs
as the rib cage expands.
Bronchioles
- Smaller tubes branching off of the
bronchus.
Alveoli
-Small moist sacs located at the end of each
bronchiole measuring 0.1 mm in diameter.
-They are round to maximize their surface area.
-This allows for the exchange of gases across their
one cell thick membranes.
-They must be moist to allow for the diffusion of
gases.
Muscle Function
Muscle can only contract.
It cannot push
Antagonistic Muscles
Muscles are usually
arranged in pairs.
This allows for movement
in more than one direction
(push and pull) antagonist relaxes, agonist contracts
Tendon
Collagen protein that joins muscle to bone.
Ligaments
Collagen protein joining bone to bone
Myofilaments
individual actin and myosin proteins
Myofibril
segments of sarcomeres joined end
to end
Muscle fiber
bundles of myofibirils enclosed in
a muscle fiber membrane
Tropomyosin
Long protein strands that prevent myosin heads from
making contact with binding sites.
The Role of Calcium Ions in Contraction
The dad whos protecting the daughter, likes calcium
Troponin
Proteins attached to tropomyosin. These are the binding
sites for calcium.
the mom thats in the upstairs (above the dad)
Calcium
Calcium binds to troponin which is attached to tropomyosin.
This creates a complex which exposes myosin binding
sites
the langerie that goes away after the mom and dad bang
3 ways that the body gets ATP
- Creatine Phosphate Breakdown -
Provides a phosphate to ADP to form ATP. - Aerobic Cellular Respiration - The mitochondria produces 36 ATP from each molecule of
glucose. - fermentation - Provides small amounts of ATP (2) if the environment is low
in oxygen.
-Lactic acid is produced within muscle during this process.
Smooth Muscles
Walls of blood vessels, digestive
tract and other internal organs,
the iris. contract involuntarily. Long, tapered, arranged in
sheets, non-striated, one nucleus
per cell.
Cardiac Muscles
Located in the heart, move involuntarily. Tubular, arranged in a
branched network, striated,
one nucleus per cell.
