BISC 102 - Test 1 Flashcards
potential energy
stored energy able to do work
energy
the ability to do work or move matter
kinetic energy
energy being used to do work
calorie
amount of energy required to raise 1 gram of water one degree celsius
metabolism
sum of the chemical reactions in a cell
oxidation-reduction (redox) reactions
transference of energized electrons from one molecule to another
oxidation
loss of electron from a molecule, atom, or ion
reduction
gain of electrons
electron transport chain
each protein accepts an electron from a molecule before it and donates the electron to the next in line
adenosine triphosphate (ATP)
temporarily stores energy released in chemical reactions
enzyme
an organic molecule that speeds up a chemical reaction without being consumed
- extremely sensitive –> can become denatured
active site
region to which substrate binds
- fit like puzzle pieces
negative feedback
product of a reaction inhibits the enzyme that controls it’s formation
- regulates the metabolic pathway
noncompetitive inhibition
product molecule binds to enzyme at location other than the active site and alters the shape of the enzyme so it can no longer bind with the substrate
competitive inhibition
reaction product binds to the active site to prevent the binding of enzyme and substrate
organic molecules
chemical compounds that contain carbon and hydrogen
- plants and autotrophs can make these organic molecules but humans must obtain them from food
hydrocarbons
organic molecules that consist almost entirely of carbon and hydrogen
monomers
chains of small molecular subunits
polymers
linked monomers
- similar to individually linked cars of a train
dehydration synthesis
chemical reaction used to link monomers together
- hydrogen is removed to leave oxygen and hydrogen that bind the monomers together - found in triglycerides
hydrolysis
chemical reaction that breaks the covalent bonds that link monomers together
- enzymes do this in your stomach and intestines to break down proteins and polymers in food
carbohydrates
organic molecules that consist of carbon, hydrogen, and oxygen (1:2:1)
monosaccharide
- smallest carbohydrate
- (5-6 carbon atoms)
- i.e. ribose, fructose, glucose
disaccharide
two monosaccharides linked by dehydration synthesis
- i.e. glucose + fructose = sucrose
glucose + galactose = lactose
polysaccharides
huge molecules consisting of hundreds of monosaccharide molecules
- i.e. cellulose (fiber)
starch (how plants store carbs)
glycogen (sugar stored in liver)
lipids
organic compounds that do not dissolve in water
- serve purpose to store energy, cushion body, insulate
triglyceride
three long hydrocarbon chains/fatty acids bonded to glycerol
glycerol
three carbon molecule that forms triglyceride backbone
carboxyl group
Carbon atom double-bonded to one oxygen and single-bonded to another oxygen carrying a hydrogen atom
- each fatty acid has a carboxyl group
saturated fat
contains all the hydrogens it possibly can
- single bonds connect carbons
- each carbon has two hydrogens
- i.e. bacon fat, butter
unsaturated fat
at least one double bond between carbon atoms
- double bonds cause kinks
- has oily consistency at room temp.
- i.e. olive oil
trans-fats
unsaturated fats whose fatty acid tails are straight not kinked
- common in fried and fast food
sterols
lipids that have four interconnected rings
- i.e. cortisone, vitamin d
cholesterol
base steroid from where body produces steroids
- i.e. hormones
protein
chain of monomers called amino acids
amino group
a nitrogen atom single-bonded to two hydrogen atoms
R group
distinguish amino acids from one another
- diverse chemical structures
peptide bond
- forms by dehydration synthesis
- covalent bond that links each amino acid to its neighbor
> dipeptide - two linked amino acids
> tripeptide - three linked amino acids
polypeptides
long chains of amino acids
- called protein once it’s folded into functional shape
- proteins may consist of one or more polypeptide chains
essential amino acids
- animal products are complete and contain all essential amino acids
- plant proteins are incomplete and are deficient in one or more amino acids
- humans are deficient in 8 amino acids
primary conformation of protein
- amino acid sequence
- determines all subsequent structural levels
secondary conformation of protein
- substructure with a defined shape
- chain of amino acid folded in coils, sheets, and loops
- each protein can have multiple areas of secondary structure
tertiary conformation of proteins
- overall shape of polypeptide
- interactions between r group and water
- water molecules surround each polypeptide
- covalent bonds between sulfur atoms in some r groups further stabilize structure
quaternary conformation of protein
- shape arises from interactions of multiple polypeptide subunits of same protein
- protein made of two polypeptides
- hemoglobin made of four polypeptide chains
biology
scientific study of life
scientific method
general way of using evidence to answer questions and test ideas
observations > question > hypothesis > prediction > test
^——proven/falsified——^
hypothesis
tentative answer to a question, testable answer
- can be verified or falsified
theory
explanation for natural phenomenon
group of hypotheses
sample size
number of individuals to be studied
- the larger the sample = the more credible the results
variable
changeable element of an experiment
independent variable
variable manipulated to determine its influence
dependent variable
depends on the outcome from the independent variable
- response measured
standardized variable
constant in an experiment to see the influence of the independent variable
controls
constant that provides basis for comparison between “normal” and “abnormal”
placebo
inert substance that resembles treatment given to experimental group
statistical significance
the probability the results arose purely by chance
digestive system
the organs that ingest food, break it down, absorb small molecules and eliminate waste
heterotroph
organism that has to consume food to get carbon and energy
autotroph
organism [plant, algae] that uses inorganic raw materials and an energy source [sunlight] to build its own organic molecules
macronutrients
required in large amounts
i.e. water, carbohydrates, lipids, proteins
micronutrients
required in small amounts
i.e. vitamins and minerals
vitamins
- organic molecules required in diet for good health
- have carbon, mostly function as assistants to enzymes
water-soluble vitamins
vitamin C, folic acid
fat-soluble
vitamin A, vitamin D
minerals
- inorganic substances required in diet
- do not have carbon
i. e. calcium, iron, phosphorus
metabolic rate
- rate of energy consumption per day
- basal metabolic rate + add. energy consumption
basla metabolic rate
amount of energy to maintain basic body functions
- humans: 1300-1800 kcal per day
- depends on activity level, body size, age, heredity
malnutrition
dietary deficiency of 1 or more essential nutrients
undernutrition
have access to nutrition but choose not to take in enough nutrients
what does food provide
- fuel for cellular work
- building materials to construct needed materials to build our bodies
- animals [including humans] must feed on plants/animals since we don’t engage in photosynthesis
herbivore
organisms that eat plants
ruminant
herbivore with four chambered organ that specializes in digesting grass
carnivore
organisms that eat other animals (often those that are herbivores)
omnivores
organisms that eat both plants and animals
mechanical digestion
breaks food physically into fragments to expose surface area to chemical digestion
i.e. chewing
chemical digestion
breakdown of food by digestive enzymes
enzymes
catalyst, speeds up a chemical reaction without being used up in the reaction
- lowers amount of energy for the reaction
- lock and key mechanism
- name often ends in ___ase
peristalsis
waves of muscle contractions that moves food through the digestive tract
incomplete system
has only one opening for food to enter and exit
complete system
has two openings, one for food to enter and one for food to exit
mouth
- mechanical [chewing to increase surface area] and chemical digestion
- specialized to break down polysaccharides
pharynx
- connects mouth to esophagus & trachea
- in swallowing, reflex tip epiglottis to close windpipe/ingest food
esophagus
- connector between mouth and stomach
- brings food to stomach
stomach
- digests proteins
- can store food for several hours
- mucus protects stomach lining
- mechanical: churns food w/ muscle contractions
- chemical: mixes food, acidic gastric juices
pepsin
- enzyme that breaks down proteins in stomach
- gastric juices discharged when food is present
chyme
food & gastric juices moved into the small intestine
gastric ulcers
- breach in stomach lining
- erosions in stomach lining caused by bacteria
- enzymes meant to breakdown food start to eat stomach
small intestine
- fats and everything else
- last digestions and absorption
- energy gained from food absorption
- highly folded to increase absorption area
lipases
fat digesting enzymes
pancreatic amylase
starch to sugar
proteases
protein digesting enzymes
villi
finger-like ripples that increase surface area
microvilli
finger-like sensors on the ripples of the small intestine
large intestine
- water and salt absorption
- waste removal
- shorter but wider than small intestine
colon
most of the large intestine length
- absorbs water, produces waste
rectum
last six inches of large intestine
anus
regulates opening of rectum
salivary glands
- releases salivary amylase to breakdown starches
liver
produces bile
gallbladder
stores bile
pancreas
releases/stores enzymes
activation energy
amount of energy required to start a reaction
