Characteristics of life

organized

require material/energy

respond to stimuli

reproduce

homeostatic

grow and develop

capacity to adapt

atoms -> molecules -> cells -> tissues -> organs -> organ systems -> organisms

1. Observation – flashlight doesn't work

2. hypothesis – bad batteries?

3. Experiment – try new batteries

4. conclusion – flashlight needed new batteries

Systematics – organizing organisms by criteria (species..genus..family..etc)

Classifications -

Taxonomy – naming an organism (ex. Homo sapien)

3 domains used to classify organisms 

All organisms are classified into 3 domains.

1. Bacteria

2. Archea

3. Eukarya

Do NOT contain membrane bound nucleus 

Archea prefer to survive in EXTREME temperatures..extreme cold/hot. Archea represent first cells evolved.

 collection of facts used to form conclusion

if..then..

cannot be broken down by chemicals  

An element cannot be broken down by means of chemical. All matter, living and non, is composed of elements.

smallest unit able to exist alone 

An atom . The atom is made of protons – electrons and neutrons – all of which depend upon the atom to survive. One to two letters create the atomic symbol.

Protons – positive

Electrons – negative

Neutrons – neutral – no charge

Atomic number

sum of protons and neutrons

 Isotopes have the same number protons – but different atomic masses.

sharing of electrons is nearly equal

electrons between water and oxygen are not equal

hydrogen bond

all living things are 70-90% water

without hydrogen bonding water would melt 100 degrees Cel making most water on

Earth Steam.

Water in the human body helps to maintain a regular temperature.

Water has high heat capacity – ex. Boiling water on stove – stays hot for a while.

Hydrophobic – Literally means water – fear. Ex. Oil. Oil and water do not mix.

 Literally means water-lover. Ex. Sugar – sugar easily dissolves into water.

Hydrophylic – Literally means water-lover. Ex. Sugar – sugar easily dissolves into water.

High iron concentration -

Substance – hydrogen donor

Considered a donor because hydrogen atoms prefer to remain neutral.

Base has high hydroxol ion concentration

Bio-Organic Molecules

Candy likes pretty necklaces

1)carbohydrates

2)lipids

3)proteins

4)nucleic acids

substances that dissociate in water, releasing hydrogen ions.

 substances that either take up hydrogen ions or release hydroxide ions.

If the number of carbon atoms in a molecule is low

polymers with amino acid monomers

central carbon atom bonded to a hydrogen atom

marks the boundary between the nonliving and the living

stores genetic material - controls metabolic functions. 

The nucleus stores genetic material which governs the characteristics of the cell and its metabolic functioning. Chromatin consists of DNA and associated proteins.

small organelles where protein synthesis occurs.

collects, sorts, packages, and distributes materials such as proteins and lipids.

separates the internal environment of the cell from the external environment. It regulates the entrance and exit of molecules into and out of the cell.

movement of molecules from a higher to a lower concentration until equilibrium is achieved and they are distributed equally.

The diffusion of water across a differentially permeable membrane due to concentration differences is called osmosis. Osmotic pressure is the pressure that develops in a system due to osmosis.

water concentration both inside and outside the cell are equal - no gain or loss of water

lower concentration of solute outside the cell - cause cells to swell or burst

higher percentage of solute outside the cell than inside the cell

Transport by Carrier Proteins

can combine only with a certain type of molecule or ion, which is then transported through the membrane.

Active Transport

Both carrier proteins and  energy are needed to transport molecules across their concentration gradient.

Vesicle Formation

Molecules that are too large to be transported by carrier proteins are moved into and out of the cell by vesicle formation.

 vesicle fuses with the plasma membrane as secretion occurs.

occurs when vesicles form around a liquid or around very small particles.