AP Biology Chapter 1

hierarchy of life

biosphere → ecosystem →community →population → organism → organ system → organ → tissues → cell → organelle → molecule → atom

emergent properties

new characteristics that appear at each successive level of biological organization

individual parts work together to do something, none of them can do alone.

example: bike; wheel, handlebar, and seat work together to move.

reductionism

reduce complex systems to simple components that are more manageable to study

eukaryotic cells

contain membrane-enclosed organelles, including DNA-containing nucleus

prokaryotic cells

lack membrane-enclosed organelles

no nucleus

• bacteria

DNA

long term genetic information storage

• stored in their nucleotide

• A,T,C,G

RNA

single-stranded worker molecule that carries out instructions to make proteins

• 
  

genes

DNA sequences that program a cell’s protein production by being transcribed into mRNAS and then into specific proteins

• process called gene expression

genome

entire library of genetic instruction that an organism inherits

cell divides

DNA first replicated and each of the two cellular offspring inherits a complete set of chromosomes

• identical to that of the parent cell

feedback regulation

controls internal conditions to keep a stable balance or drive a specific process to an end

negative feedback loop

response reduce/change initial stimulus to bring back to set point

ex: body gets hot so starts sweating to cool down

positive feedback loop

increase and accelerate change (childbirth)

natural selection

individuals with inherited traits that are better suited to the environment are more likely to survive and reproduce → leading only to better traits animals to continue surviving

inductive reasoning

move from specific observations to generalities

deductive reasoning

move from general to specific

qualitative data

non-numerical information that describes qualities, characteristics, and meanings

quantitive data

numerical information that can be measured, counted, or expressed with a value

hypotheses

• testable by experiments or by observations (if exp not possible)

controlled experiments

a scientific test designed to isolate the effect of a single variable by keeping all other conditions constant

theory

broad in scope and generates new hypotheses

• supported by a large body of evidence

science

• social activity

• build off each others work

• must be able to repeat others results (integrity is key)

• diversity

technology

consists of any method of device that applies scientific knowledge for a specific purpose that affects society

flow of energy

Energy flows continuously through ecosystems and is eventually lost as heat

flow of matter

matter cycles continuously within an ecosystem

• atoms are never created or destroyed; they change forms and move between biotic (living) and abiotic (non-living) parts of the ecosystem.