biology final exam review

• the 7 properties that characterize life:

1. cells & order (organization)
2. regulation (homeostasis)
3. growth & development
4. energy processing
5. response to environment
6. reproduction
7. evolutionary adaptation

• discovery science: 

describes natural structures & processes, mostly about describing nature by observation & senses- inductive reasoning

• hypothesis-based science: 

mostly about explaining nature- investigation

• quantitative data: 

recorded measurements

• qualitative data: 

recorded descriptions (observation)

• the five stages of the scientific method:

1. observation --> question/problem
2. hypothesis
3. experimentation
4. data
5. accept/reject hypothesis (results)

• role of natural selection in evolution: 

natural selection is the driving force behind evolution. natural selection is the process by which selection accumulates favorable traits over multiple generations

• four major elements that make up 96% of living matter for humans:

1. oxygen
2. nitrogen
3. hydrogen
4. carbon

• element: 

substance that can't be broken down by chemical reactions

• compound: 

2+ different elements combined in a fixed ratio

• neutron: 

neutral charge, determines isotopes

• electron: 

negative charge, involved in chemical reactions btwn atoms, determine chemical behavior

• proton: 

positive charge, determine element

• atomic number: 

proton number

• mass number:

proton + neutrons, measured in daltons

• be able to interpret and draw electron distribution diagrams

• polar covalent bonds:

electrons are shared unequally

• nonpolar covalent bonds:

electrons are shared equally

• hydrogen bonds:

weak electrical attractions bc of polarity of water

• ionic bonds

electrons are transferred from one atom to another

• properties of water that emerge as a result of its ability to form hydrogen bonds:

-cohesion: water molecules are attracted to one another
-adhesion: water molecules are attracted to other objects
-surface tension: measure of how difficult it is to stretch/break surface of a liquid
-high specific heat: strong resistance to changes in temperature
-heat of vaporization: can absorb or release heat w only slight changes in own temperature
-density: frozen water floats (less dense than water bc molecules move apart/expand)
-universal solvent

• hydrophobic: 

water-fearing; nonpolar

• hydrophilic:

water-loving; polar

• solute: 

dissolved substance

• solvent: 

dissolves other substances

• solution:

a mixture of a solvent & solute

• acid: 

1-6 on pH scale, more hydroniom ion concentration

• base: 

8-14 on pH scale, reduces hydroniom ion concentration

• interpret the pH scale

• carbohydrates:

sugars, starches- mono/poly-saccharides

source of dietary energy

• lipids:

not a polymer

hydrophobic/nonpolar

long-term energy storage, cushions organs, insulates body, hormones 

• proteins:

made up of polypeptides

functions: structural support, storage, enzymes, transport, cellular communications, movement, defense against foreign substances

• nucleic acids:

store info, provide direction for building proteins, include DNA & RNA

polynucleotides

• carbon skeletons:

may vary in length & shape- can be branching, linear, etc.
this variation contributes to the diversity and complexity of organic molecules bc carbon chains form the skeletons of most organic molecules

• dehydration reactions:

monomers connect in a reaction- 2 molecules covalently bond through loss of water molecule

anabolic

• hydrolysis reactions:

break down polymer using addition of water molecule 

catabolic

• functional groups: hydroxyl, carboxyl, amino:

• prokaryotic cell:

 simple, no nucleus or organelles, has cell wall

• eukaryotic cell:

more complex, has organelles, no cell wall

• animal cell:

has lysosomes & centrioles

• plant cell:

has central vacuole, cell wall, chloroplasts

• cell membranes:

made of phospholipid bi-layer & embedded proteins

nonpolar can get through membrane

• nucleus:

chief executive of eukaryotic cell, contains DNA, separated from cytoplasm

• endomembrane system:

synthesizes proteins & lipids

-nuclear envelope (allow materials to move btwn nucleus & cytoplasm)

-smooth & rough ER (smooth makes lipid, rough makes ribosomes) 

-golgi apparatatus (receives, refines, stories, transport chemical products out of cell)

-lysosomes (hydrolytic enzymes- breakdown)

-vacuoles (membrane bound, large sacs budding from ER, GA, or membrane)

-plasma membrane (selective barrier)

• be able to match up all metabolic and cellular processes studied with their cellular location within the cell

DNA replication: in nucleus

transcription: in nucleus

translation: in cytoplasm (ribosome)

cellular respiration: in mitochondria (?)

• energy:

ability to promote change or movement of matter, capacity to do work

kinetic: moving, motion

potential: stored energy

• metabolism:

total of all chemical reactions in the organism

transforms matter & energy subject to laws of thermodynamics

• catabolic pathway:

release/yield energy by breaking down complex molecules

• anabolic pathway:

consume/require energy to build complex molecules

• catalysts:

enzymes that speed up chemical reactions w/o being permanently changed/consumed

increase rate of chemical reaction by lowering energy of activation

enzyme binds to substrate

• first law of thermodynamics: 

(principle of conservation of energy) energy of the universe is constant, can be transferred/transform, not created/destroyed

• second law of thermodynamics: 

provides us w criteria for predicting direction of metabolic process; recognizes condition of matter & energy called entropy. more entropy = more disorder/chaos

• simple diffusion: 

transport of nonpolar lipid soluble solute

• facilitated diffusion: 

polar or ionic solute

• osmosis: 

diffusion of free water across a membrane

• passive transport: 

high to low, going w the concentration gradient, no energy investment

• active transport: 

move against gradient, requires ATP/energy

• tonicity: 

ability of solution to cause cell to gain/lose water, depends in part on concentration of solutes that can't cross membrane

• hypertonic: 

outside solute concentration > inside- cell lose water, shrivels

• hypotonic: 

outside solute concentration < inside- cell gains water

• isotonic: 

solute concentration outside cell = inside cell

• equation for cellular respiration: 

• key points about redox reactions:

chemical reactions that transfer electrons through hydrogen atoms from one substance to another

oxidation= loss of electrons/energy

reduction= gain of electrons/energy (reduction in charge)

glucose is oxidized/loses electron

oxygen is reduced/gains electron

• cells obtain the energy to do cellular work through ATP
• how ATP performs the work of the cell:

the bonds between the phosphate groups of ATP's tail can be broken by hydrolysis. energy is released from ATP when the terminal phosphate bond is broken. this release of energy comes from the chemical change to a state of lower free energy, not from the phosphate bonds themselves.

• diagram of energy flow & chemical cycling & the relationship btwn cellular respiration & photosynthesis:

• structure of DNA & RNA & their nucleotide monomers:

• mechanism of DNA replication:

• mechanism of transcription:

• mechanism of translation:

• mutation:

any change in nucleotide sequence of DNA

• silent mutation: 

have no effect on amino acid bc redundancy of genetic code

• nonsense mutation: 

changes codon into a stop codon bc stop codons don't code for an amino acid

• missense mutation: 

create codons that still code for amino acid but the wrong one

• phases of the eukaryotic cell cycle and describe the sequence of events during mitotic cell division:

• main events that characterize/distinguish mitosis from meiosis (meiosis I and II):

meiosis has 2 divisions, mitosis has 1

meiosis has genetic variability, mitosis doesn't

meiosis is for reproduction & forms zygotes

• somatic cells: 

all cells that are not sex cells (divide by mitotic cell division)

diploid, 46 chromosomes

• gametes:

sex cells (divide by meiosis)

• autosomal chromosomes:

first 22 pairs of chromosomes that do not determine sex

• sex chromosomes:

one of the 23 pairs of chromosomes in the human, contains genes that will determine the sex of the individual

• haploid: 

23 chromosomes

• diploid: 

46 chromosomes

• three events that contribute to genetic variation in sexually reproducing organisms:

1. crossing over (2 homologous chromosomes exchange DNA segments- prophase I)
2. independent assortment (side-by-side orientation of pairs= chance- metaphase I)
3. random fertilization (all sperm are distinct)

• genotype:

genetic make-up

• phenotype:

physical trait

• dominant allele:

allele whose trait always shows up in the organism when the allele is present

• recessive allele:

allele that is masked when a dominant allele is present

• trait:

genetically determined characteristic

• homozygous genotype:

(AA, aa)

2 identical alleles for a trait

• heterozygous genotype:

(Aa)

2 different alleles for a trait

• Mendel’s law of segregation:

2 alleles separate/segregate during meiosis & end up in different gametes which carry only 1 allele for each gene

• law of independent assortment:

that genes separate independently of one another in meiosis

• be able to use a Punnett square to predict the phenotypic and genotypic ratios of the F2 generation from single-factor crosses
• be able to interpret pedigree charts and determine the phenotype and genotype of family members
• be able to explain the effects of autosomal recessive and dominant human genetic disorders using Punnett squares