BIO104- Chapter 1

exam 1 - 9/26

How are we connected to the environment around us?

Livings things have shared resources

\-energy

\-space

\-air

\-water

\-nutrients

Biological world is

a series of cycles

The end of one process…

leads to the start of another

each living individual is an…

organism

life is defined by its

characteristics

What is life? (WIL)

Consists of ordered structures

Life is organized into units called ______

cells

Must obtain and use ______ to survive (WIL)

energy

Maintain ____________________ (WIL)

internal constancy (homeostasis)

Cells that can ________ to their environment (WIL)

respond

Use ___ to transmit genetic information (WIL)

DNA

Grow and change in organized ways (_______)

develop

________ themselves

reproduce

_______ to become adapted to their environment

evolve

What are the characteristics of life?

1. organization
2. energy
3. internal constancy
4. DNA
5. reproduction, growth, and development
6. evolution

biosphere

parts of the earth’s air, water, and soil where life is found

ecosystem

a community of different species interacting with one another and with their nonliving environment of matter and energy

community

populations of different species living in a particular place, and potentially interacting with each other

population

a group of individuals of the same species living in a particular place

organism

an individual living being

cell

the fundamental structural and functional unit of life

molecule

chemical combination of two or more atoms of the same or different elements

atom

smallest unit of a chemical element that exhibits its chemical properties

How is life organized?

atoms→molecules→organelles→cells→tissues→organs→organ systems→individual organisms→populations→communities→ecosystems→biosphere→

Every living thing is made up of

one or more cells

Biochemistry processes take place inside

cells to carry out the basic functions of life

Simple single-cells organisms are

unicellular

More complex organisms are

multicellular

Emergent properties

arise at each level of biological organization

Energy is needed for…

1. maintenance and upkeep of cells
2. carrying out chemical reactions
3. building important molecules
4. transporting molecules inside, out of, and among cells
5. maintaining internal constancy
6. reproducing, growing, and developing

Producers

\-(autotrophs) capture light and convert it to chemical energy

\-include plants, some protists, and many prokaryotes

Consumers

\-(heterotrophs) must get their energy from other organisms

\-are generally animals; some protists and others are prokaryotes

Decomposers

\-(heterotrophs)

\-include fungi, some animals, some protists, and many prokaryotes

Cell membranes control…

the flow of materials in and out of the cell

\-this allows the cell to respond to the external environment

Homeostasis

the process by which a cell or organism maintains internal constancy

First example of homeostasis

\-humans have an internal thermostat that helps maintain temperature homeostasis

\-woman shivers when she feels cold and puts on a jacket

Second example of homeostasis

\-organisms fluctuate around their optimal balance of nutrients, sugar, salt, and water

\-this means they must be able to sense and respond to stimuli in their environment

Asexual reproduction

\-only one parent is involved, and the offspring are genetically identical to the parent

\-successful strategy in unchanging environments

ex. strawberry plants reproduce asexually

Sexual reproduction

\-two parents are involved, and the offspring are genetically different from the parent

\-successful strategy in changing environments since offspring are unlike either parent

ex. most plants and animals reproduce sexually

Evolution

genetic change over time in a population

How is it that organisms seem perfectly suited to their genes?

Ex. Pigmy seahorse blends into the coral habitat where it lives, because of its genes

Other seahorses, with different genes, may not blend in as well

Taxonomy

reveals evolutionary relationships

What does classifying organisms help?

It helps show how closely related they are to each other

All organisms share common ancestors

Humans are more closely related to a kangaroo than a platypus because we share a more recent common ancestor with the kangaroo

8 levels of taxonomic hierarchy

1. specific descriptor sapiens
2. genus homo
3. family hominidae
4. order primates
5. class mammalia
6. phylum chordata
7. kingdom animalia
8. domain eukarya

Three main branches in the tree of life

1. domain bacteria
2. domain archaea
3. domain eukarya

Species are categorized into…

one of three domains

Domains are divided into…

kingdoms

Prokaryotes

\-most ancient forms of life

\-they are small, simple in structure, and lack a nucleus

\-bacteria and archaea are 2 domains of prokaryotes

Eukaryotes

\-evolved billions of years after prokaryotes

\-they are larger and more complex, with many internal parts including a nucleus and other membranous organelles with specialized functions

\-4 kingdoms: protists, fungi, plants, and animals are eukaryotes

Eukarya, kingdom Protista

\-protists are the most diverse group of eukaryotes

\-unicellular or multicellular

\-autotrophs or heterotrophs

Eukarya, kingdom Animalia

\-animals are a familiar group of Eukaryotes, including vertebrates such as fish, frogs, and humans

\-multicellular

\-heterotrophs

Eukarya, kingdom Fungi

\-fungi are nature’s decomposers

\-multicellular

\-heterotrophs

Eukarya, kingdom Plantae

\-plants are producers that capture light energy from the sun

\-multicellular

\-autotrophs