Unit D Human Systems Flashcards
Catabolic metabolism
large chemicals are broken into smaller ones
Energy is released
Anabolic metabolism
complex chemicals are built from smaller ones
Energy is required
Neutral:
pH ~7
Neutralization reaction (acid + base → salt + water)
Hydrogen ions = hydroxide ions
Acidic:
pH < 7
Hydrogen ions > hydroxide ions
Basic:
pH > 7
Hydrogen ions < hydroxide ions
Inorganic Molecules -
no carbon bound to hydrogen:
Minerals
Water
Organic Molecules
contain carbon and hydrogen bound
Carbohydrates
Proteins
Nucleic Acids
Lipids (Fats)
Vitamins
Most large biological molecules are
polymers
Polymers are long chains of repeating molecular subunits, or building blocks, called
monomers
Monosaccharides:
1 sugar (eg. glucose, fructose, galactose)
Used as monomers to build more complex sugars (polymers / polysaccharides)
Disaccharides:
Two monosaccharides put together by dehydration synthesis
Can be broken down into the monosaccharides by hydrolysis to break the bond joining the two monosaccharides.
Polysaccharides:
many sugar units/monosaccharides put together (eg. starch, glycogen, cellulose)
in dehydration synthesis,
large biological molecules assemble.
A water molecule is released in the process (dehydration = remove water) and this allows for two monomers to join with a covalent bond. This is an anabolic reaction.
In hydrolysis,
polymers are broken down into monomers.
Carbohydrates are ____ We can identify them by their suffix ___
sugars, “-ose”
carbohydrates have a ratio of…
a carbon-hydrogen-oxygen ratio of 1:2:1
glucose, fructose, and galactose are all examples of
monosaccharides
Lipids
non-polar molecules (insoluble in water)
often made of a glycerol backbone and a fatty acids combined through dehydration synthesis
lipid Functions:
structural materials (cell membranes, cushion delicate organs, carrier for fat soluble vitamins [A, D, E, K], raw materials of hormones)
energy reservoirs (excess glycogen in animals is converted into fat)
four Groups:
Triglycerides: fats, oils
Phospholipids: membranes
Waxes
Sterols: cholesterol, steroids
Animal triglycerides (fats)
(Saturated fats)
Saturated fats have single bonds throughout and are quite stable so these fats are difficult for our bodies to break down.
Solid (fat) or semi-solid (oil) at room temperature
Plant triglycerides (oils)
(Unsaturated fats)
Polyunsaturated meaning they have some double bonds that are more reactive than single bonds, so they are easier for our bodies to break down.
Sterols include..
Cholesterol
Steroids (hormones; chemical messengers)
Male sex hormones are called androgens
Female sex hormones are called estrogens
Liposome is…
double layered sphere used to:
Carry drugs throughout the body
Gene therapy: introduce new DNA to cells
Essential Amino Acids:
are amino acids that our bodies cannot produce. We get these amino acids from the foods we eat
The ____ is what the protein is made up of
primary structure
The _____ are the initial coils and folds that occur, based on the hydrogen bonds between amino acids
secondary structure
The ____ is the irregular folding that occurs as a result of the interactions between the R-groups [chains/branches on amino acid].
tertiary structure
The ____ occurs when there is clustering of two or more polypeptides into one macromolecule.
quarternary structure
Denature means…
bonds are disrupted causing temporary change. The protein can resume its original shape once the factor is removed
Coagulation means…
results in a permanent change in the protein shape. (Eg. boiling an egg)
Exposing a protein to excessive heat, radiation, or pH change can alter the protein’s…
shape or function.
testing for Carbohydrates…
to test for simple sugars, test with Benedict’s reagent and heat. A colour change will be present if a reducing sugar is present.
testing for Starch…
to test for complex sugars, we test with iodine. If starch is present, there will be a dark purple colour.
testing for proteins…
to test for proteins we do a biuret test which will react with peptide bonds. The more bonds, the darker the purple colour
testing for lipids…
a common way to test for lipids is using a brown paper bag to do a translucence test. The brown paper bag will absorb lipids.
Enzymes are…
catalysts. This means they are able to speed up the rate of reactions WITHOUT being consumed/changed in the process.
permit low temperature reactions by reducing the activation energy.
A good indication that you have an enzyme is that it will end in
“-ase”
Enzyme Parts:
Active Site: site of reaction
Substrate: substance changed by enzyme, can be built or split (anabolic or catabolic)
Enzyme Models:
Lock & Key Model: Active site is rigid and fits only the properly shaped substrate
Induced Fit Model: Active site is flexible and can change to fit the substrate
Enzyme reaction rate (activity) is affected by:
Substrate Molecule Concentration,
Temperature,
Competitive Inhibitors
Substrate Molecule Concentration is..
the more substrate molecules that are available, the greater the number of interactions between the substrate and enzyme = increase in reaction rate!
Ingestion is…
act of eating
Digestion is..
process of food breakdown (enzymatic hydrolysis)
Absorption…
the uptake of small molecules
Egestion is …
removal of undigested material
Mechanical [Physical] Digestion is…
involves physically breaking the food into smaller pieces. Mechanical digestion includes chewing (mastication), churning of food in the stomach, and segmentation in the small intestine.
Chemical Digestion is…
involves breaking down the food into simpler nutrients with enzymes. Chemical digestion begins in the mouth with salivary amylase.
salivary glands contain…
contains salivary amylase which breaks down starch (chemical digestion).
The ____ is a muscular tube that carries food to the stomach.
esophagus
Food is moved by ____ which are rhythmic contractions that force food down to the stomach.
peristalsis,
At the distal end of the esophagus there is a sphincter called the ___ that leads to the stomach.
cardiac sphincter or lower esophageal sphincter (LES)
Food remains in the stomach for about ____, before exiting the____ into the Small Intestine.
2-4 hours, Pyloric Sphincter
Pepsin is..
an enzyme that is used to break down proteins
Rennin (Chymosin) is ….
a milk clotting protein that is important in digestion for babies (tapers off early in place of pepsin
Endoscope is..
a flexible tube shaped instrument with a lens and light source that can be fitted with a laser to diagnose problems and/or perform surgery.
The small intestine is…
the primary site of chemical digestion and nutrient absorption
three segments to the small intestine:
Duodenum
Jejunum
Ileum
The small intestines ridges have finger like projections called____ that help with absorption and mixing food with enzymes.
Villi (singular = villus)
The villi have small hair-like projections called ___ to help with absorption even more!
microvilli
Blood vessels (capillary network) absorbs..
absorb amino acids and monosaccharides. Will also absorb some water
Lacteal is…
a small vessel within the small intestine villi that absorbs fatty acids (digested fats) into the lymphatic system
The large intestine is responsible for…
storing leftover organic material (feces) and some absorption
The pocket and small extension at the start of the long intestine are called the ___ and ___
cecum and appendix.
the colon and has three parts called..
(ascending, transverse, descending).
the major part of the long intestine is referred to as the…
colon
The last part of the long intestine is the ___
rectum
Functions of the large intestine:
Absorb water and electrolytes
Produces and absorbs vitamins [Vitamin B & K]
Forms and propels feces to rectum for elimination
Home to E. coli and other bacteria
the function of the rectum is
storing feces before egestion.