1.1 Introduction to Biology

why study bio

life processes

apply knowledge (ex. disease cures)

GMO

life

carbon based, organic, water major ingredient

cell

basic unit of life

emergent properties

new characteristic that complex system gains when individual parts interact

ex. reproduction, growth/development, order/structure, metabolism, homeostasis, respiration, response to environmental stimuli, autonomous mvmnt, dormancy, diversity, adaptation, evolution

reproduction

dna passed down, and starting materials to build life such as ribosomes provided by progenitor cells

growth and development

more obvious in multicellular organisms than unicellular

order and structure

structure correlates with function, this order is autonomously. inanimate may have order but it is artificial

metabolism

all biochemical reactions that happen in a living cell. energy consumption and release happen constantly. eat organic foods, minerals, other nutrients. they can make and breakdown small and large molecules

homeostasis

maintain internal conditions such as pH, salt concentration, temperature. many biochemical functions depend on this homeostasis

respiration

consume oxygen to break down organic molecules to release energy and CO2. energy consumption and release. *some unicellular (fermentation-no O2)

response to environmental stimuli

maintain homeostasis despite changing surroundings

autonomous mvmnt

fungi/plants move towards light. bacteria, protists, animals move

dormancy

spore/seed germinate. viable seeds are living

diversity

important bc can survive against biological, physical and chem challenges in life

adaptation

survival of the fittest based on environmental/predator challenges they face

evolution

genetic changes over long period of time

model systems

representative organism/cell type used to conduct simple to complex biological experiments

reductionism

to understand complex living thing, study its basic building block (cell, tissue, molecule). can miss bigger picture or how parts interact

holism

whole greater than sum of its parts. relies on emergence (new properties appear when simple parts join together into a complex system). study entire organism/environment. hard to test/too vague or too complex. unethical and $$$ to test whole organism

in vivo

research on whole living organism ex. animal. provides total physiological context, but $$$, unethical, hard to isolate exact mechanisms

in vitro

in artificial environment outside organism. ex. cell culture in Petri dish, test tube enzyme assay. high experimental control but lacks whole body dynamics

in situ

in exact natural location ex. straining mRNA inside an intact tissue slice. limited to visualization/local probing, doesn’t test systemic functional changes

in silico

computer software. fast cheap but relies on accuracy of software

scientific reasoning

hypothesis based on some observation, prediction, experimentation with proper controls allows conclusions using inductive or deductive approach

inductive approach

rare; specific observations to broad generalizations/theories ex. observe species →evolution, temperature/co2 measurements →global warming

deductive approach

general to specific testable predictions

controlled experiment

defined environmental and physical conditions, whereas control is one of the treatments that remains unchanged to compare against results from treatments.

positive control

definite positive result (effect occurs) proves test can detect a positive signal and is not failing (prevent false negatives). uses a known active substance or sample

negative control

no effect or change. proves test does not trigger false signal from outside noise/contamination. blank, plain solvent/untreated sample

experiment results repeated by several scientist under various condition→

theory (if unifying concept)→law

taxonomy

identifying, naming, and classifying organisms based on genetic and physical characteristics

phylogeny

genetic sequences to organize organisms based on homology (similarity of DNA sequences) of selected genetic markers.

domain→kingdom→phylum→class→

order→family→genus→speciesb

bacteria

no nucleus, diverse unicellular (prokaryotes)

archae

prokaryotic but has some parts of eukaryotic cells. survive in extreme conditions

eukarya

true membrane bound nucleus

protista

unicellular eukaryotes that are heterotrophic ex. paramecium, amoeba, phototropic. and someone multicellular such as kelp

fungi

heterotrophic ex. yeast

plantae

higher plants

flowering plants (angiosperms)

non flowering plants (gymnosperms). include monocots and dicots. all photoautotrophs

animalia

includes all animals. multicellular and heterotrophic

atoms→molecules→macromolecules (protein, carbs, lipids)→parts of cells→

cells→tissues→organs→organ systems→multicellular organisms→population→community→ecosystem→biomes→biosphere