Exam 1 Flashcards
5 characteristics of something living
- composed of cellular organisms
- way to replicate/reproduce
- genetic information (and way to process it)
- Take in and use energy
- undergoes evolution
Hypothesis
uncertain explanation for observation (Allows for falsification)
Theory
also false able like a hypothesis (still supported by lots of evidence)
Takes the results of many hypothesis and combines them together to create one overarching explanation for a phenomenon
prediction
Prediction is similar to hypothesis
Differs because it makes a more specific guess on the outcome of the experiment
Laws
does not explain why
Just provides a cause and effect relationship
control group
Group where independent variable is left unchanged, this allows something to compare the experimental group to
placebo
treatment or pill that doesn’t actually do anything. This is to measure the placebo effect against the real thing.
double blind study
experiment in which both the researcher and the participants do not know who received the placebo.
This eliminates experimenter and placebo bias
Ranking of bond strength (in context of biology)
- Covalent bonds
- ionic
- Hydrogen bonds
*note that usually ionic is stronger than covalent but in the context of water, covalent is stronger
Hydrophilic
Tendency to dissolve in water
Ions and polar molecules are hydrophilic
surface tension
cohesion allows water to resist forces that increase surface area (makes water stay together and generally keep shapes that minimize surface area)
Cohesion
tendency of water molecules to stick to one another
Adhesion
Tendency of water molecules to stick to certain surfaces
High specific heat of water
Waters tendency to maintain its temperature even when heat is added
*Due to strong hydrogen bonds between water molecules
Hydrophobic
Does not easily dissolve in water
mainly non polar molecules like lipids
carbon skeleton
Carbon is often known as the backbone of lots of organic molecules
Hydroxyl group
-OH group
Makes molecules more polar so they more easily dissolve in water, found in alcohols
Phosphate group
-PO4
More than one phosphate linked together allows for storage of lots of chemical energy
sulfhydryl group
-SH
When present in proteins it can make s-s bonds which contributes to overall structure
Amino group
-NH2
Acts as a base, large component of amino acids
Carboxyl group
C double bonded to one O and single bonded to another O
Commonly found in acids (amino acids)
carbonyl group
C double bonded to an O (and possibly single bonded to an H
Found in proteins, peptides and carbohydrates
Bond energy
Non polar bonds usually store more energy than polar bonds
Monosaccharide
Simple sugar building block
1 ring
-glucose (used for cellular respiration)
-fructose
-galactose
Can differ in placement of carbonyl group and orientation of hydroxyl group
Disaccharide
Two monosaccharides bound together
2 rings
*these molecules bond covalently, the structure of these glycosidic linkages can determine the function of the carbohydrate
Polysaccharide
Many monomers linked together
Alpha vs beta polysaccharides
Alpha- glycosidic bonds place the hydroxyl group on the first carbon below the plane
Beta- the glycosidic bonds place hydroxyl group above the plane
Cellulose
polysaccharide that provides the structure for plant cell walls
Carbohydrate functions
-Energy storage (glucose)
-Cell structure (cellulose in cell walls)
- identity markers (blood type)
Proteins and amino acids
The proteins is the polymer while the amino acids are the monomers
Amino acid structure
4 groups (H, R group or side chain, carboxyl group and amino group) covalently bonded to a C atom
R group functions
Primary structure
refers to the sequence of amino acids covalently bonded
*the covalent bond that links the amino acids are known as peptide bonds
secondary structure
refers to the folding of the protein created by hydrogen bonding from the non R groups
Tertiary structure
Overall three dimensional structure that’s created from R group interactions (interactions within the same chain)
Quaternary structure
Refers to how multiple subunits of polypeptide chains interact to form a protein complex (interactions with different chains)
Nucleic acids and nucleotides
nucleotides are the monomers that make up the polymer nucleic acid
Nucleotide parts
Phosphate group
5-Carbon sugar
Nitrogenous base
*note for 5-carbon sugar, DNA has one less oxygen bonded than RNA (hence deoxy)
Phosphodiester linkages
Type of bonds that nucleotides use
forms the sugar phosphate backbone
Saturated vs unsaturated fats
Unsaturated fats have at least one Carbon double bond leading to kinks in the structure
*this is why unsaturated fats are usually liquid at room temp
*also note that these kinks make membranes more permeable
Phospholipid bilayers and permeability
selectively permeable, outer “heads” are charged (polar) and inner “tails” are not charged (non polar)
Triglycerides
used for energy storage
fatty acids connected to strings of C-C bonds
very nonpolar
Phospholipids
steroids
