BIO- ch 1 exploring life

scientific study of life

high degree of order

heiarchy with structural levels each with emergent properties

biosphere>ecosystems>communities>populations>organisms>organs and organ systems>tissues>cells>organelles>molecules

components of cells

fundamental unit of structure and function of living things

uptake and processing of nutrients, excretion of waste, response to environmental stimuli, reproduction

tissues- similar cells grouped together
organs- several tissues coordinated
organ system- several organs

localized groups of organisms belonging to a community--- all the individals of a species living within bounds of a specified area. ex population of maple trees in a forest

populations of several species inhabiting a particular area.

all the living and nonliving things in a particular area that interact (soil, water, gases, light, trees, animals). the organisms and environment effect each other.

all the environments on earth that are inhabited by life

1/ cycling of nutrients
2. flow of energy from sunlight to producers to consumers (often involves transformation of energy from one form to another, where some is lost to surroundings as heat)

most ecosystems producers are plants and other photosynthetic organisms that convert light energy into chem energy

organisms that feed on producers and other consumers

chemical nutrients recycles within an ecosystem, energy flows through entering as light exiting as heat

organism's basic unit of structure and function, lowest level of structure that can perform the activities of life

understanding how cells work

deoxyribonucleic acid or DNA, directs cell's activities

substance of gene, units of inheritance that transmit info from parent to offspring, directs development and maitenence of entire organism

one long dna molecules with tons of genes arranged along the length

encode the information for building the cells other molecules

program cell's producion of proteins

one of 4 nucleotides (chemical bonding blocks) that encode information with chemical letter

codes for a specific protein w/ shape and function

involved in almost all cell activities, tools to build and maintain cell

essentially the same in all forms of life, universal so it is possible to produce proteins only found in other organisms

library of genetic instructions that an organism inherits

enclosing every cell, regulate passage of material btwn cell and surroundings

prokaryotic- microorganisms called bacteria and archaea, dna is not separated from cytoplasm in a nucleus and no membrane enclosed organelles
eukaryotic all other forms of life, more complex, subdivided by internal membranes into organelles

nucleus, contains chromosomes

combination of coomponents in a complex organization

examples: cells, organisms, ecosystems

IMPORTANCE OF STRUCTURAL ARRANGEMENT: moving up biological order properties emerge that are not present at lower levels. result from arrangements and interactions between components as complexity increases.

ex: thoughts and memories are emergent properties of a complex network of neurons. recycling of nutrients depends on network of diverse organisms interacting with each other and soil and air

reducing comple systems to simpler components

it is impossible to understand an organism without taking it part, but we cant fully explain a higher level of organization by breaking it down into its component parts

sequencing of the genome of humans and other species

tries to model dynamic behavior of whole biological systems so they can see how changing a variable effects the system
-- increased understanding of protein functions and sequencing of data makes systems biology more important

1960s elaborate models digramming interactions of species and nonliving components in ecosystem

1. high throughput technology methods that can analyze materials quickly and produce huge amounts of data (like dna sequencing machines)
2. bioinformatics- huge databases from number 1 require software and mathematical models to process and integrate info.
3. interdisciplinary research teams- sys bio teams involve many scientists besiides biologists

ensure a dynamic balance in living systems

protein molecules that catalyze (accelerate) chemical processes within cells
- each enzyme catalyzes a specific chem reaction
- many times ractions are linked into chemical pathways, each step with its own enzyme

output or product of a process regulates that process

negative feedback, accumulation of an end product slows or stops process

end product speeds up its own production example- platelets in damaged blood vessel

vertical- atoms to viosphere
horizontal- diversity of life, organisms thoughout history

classifies species into heirarchial order

until past decade: 5 kingdoms
now 6 7 8 or even dozens of kingdoms because of comparisons of dna among organisms

bacteria, archaea, eukarya (higher than kingdoms)

bacteria and archae are prokaryotes

plantae, fungi, animalia-- distinguished party by modes of nutrition (photosynth, decomposers, ingestion)

DNA

evolution

evolution in 1859 with on the origin of spcies by natural selection--
1. descent with modification- unity in kinship but diversity in modifications
2. mechanism for descent with modification was natural selection

individual variation among a population, and overpopulation and competition (more offspring than environment can support so they struggle to exist)

inferences-- 1. unequal reproductive success (better offpring from those best suited for environment) 2- evelutionary adaptation00 heritable traits that enhance survival and success increase in frequency

adaptation to different environmental encounters--- 14 species of finch diversified from the ancester to exploit food sources on the islands

long evolutionary history- shared ancestor for all living things

discovery science- describes structure s and processes through observation and analysis of data
& hyptothesis science- explains nature

derive generalizations based on specific observations

heart of science, asking queions about nature, involves proposing and testing hypoth

general--> specific
extrapolate to a specific result we should expect if premises are true
--- predictions about what we shoudl see if hyp is correct

"if... then"

answers a question
must be testable and falsifiable
-- frame two or more hypothesis and design experments to falsify them

idealized process, very rarely followed rigidly

controlled, test the effect of one variable by cancelling out the effects of the other (brown were controls)

natural causes for natural phenomena

broader in scope than a ypothesis-- general enough to generate many new specific hypoth that can be tested, support by more evidence, widely accepted, reject if new data comes about

range from lifelike reps to symbolic schematics

publications, seminars, meetings

switch in focus of research

applies scientific knowledge for some specific purpose
- results from scientific discoveries applied to development of goods and services
- interdependent with science
- depends on human need
- difficult choices with other factors besides science

- revolutionized the pharm industry
- important impact on agriculture and law