biology midterm review

biology

study of life

scientific method

 way we investigate the world around us using controlled experiments

quantitative data

numerical data

qualitative data

descriptive

metric conversions

**kilo(k), hecto(h), deca(da), base unit(m,g,L), deci(d), centi(c), milli(m)**   **king henry died by drinking chocolate milk**

observation vs. inference

**observation: using ur 5 senses**  

**inference: how u interpret ur observation**

hypothesis

educated guess based on observations, must be testable

controlled experiment

only 1 variable is being manipulated

control vs. experimental group

**control- one group that receives no experimental treatment bc we want to use it for comparison**     

**experimental: has the i. variable being manipulated**

independent variable

**the 1 variable that is manipulated in a controlled experiment**

dependent variable

**measurable outcome, depends on how we manipulate the i. variable**

Graphing Data

**i.v is on x-axis**

**d.v is on y-axis**

homeostasis

maintaining a stable internal environment

evolution/adaptation

**organisms have the ability to grow and change to environmental conditions**

metabolism

**sum of all chemical reactions that occur in a living organism**

Characteristics of all living things

1. **made up of cells**
2. **organization**
3. **growth and development**
4. **reproduce**
5. **genetic material**
6. **evolution over time**
7. **response to stimuli**
8. **requires energy**

Levels of organization in biology

**organelles, cells, tissue, organ, organ systems, organism**

Cell Theory

1. **all organisms are made of one or more cells**
2. **all cells come from preexisting cells**
3. **the cell is the basic unit of structure and life**

prokaryotes vs. eukaryotes

**pro: no nucleus, single celled**    

**euk: nucleus, multi/single celled**

organelles

**tiny structures inside of a cell that perform specific functions** 

lysosome

**contains enzymes, garbage disposal of the cell**

mitochondria

**powerhouse of the cell, produce ATP, release energy**

nucleus

**control center of the cell, contains chromatin**

ribosomes

**make proteins, made up of genetic material, made in nucleus, located on rough ER**

Golgi apparatus

**packages products for secretion from the cell, forms vesicles**

endoplasmic reticulum: Smooth vs. Rough

**smooth: no ribosomes, makes proteins**  

**rough: has ribosomes, makes lipids** 

chloroplast

**contain chlorophyll that absorbs light, located in plant cells**

cytoskeleton

**gives shape and makes a cell rigid**

vacuole

**contain enzymes, in plant cells, regulate water contents of the cell**

Difference between plant and animal cell

**plant: has cell wall and cell membrane**   

**animal: cell membrane**

Cell membrane

**regulates what enters and leaves the cell, encloses contents of cell**

Selectively Permeable Membrane

**allows only certain things to enter/exit the cell** 

phospholipid bilayer

**cell membrane**

possible benefits from studying biology

**modern medicine, agriculture** 

Parts and charge of an atom

**subatomic particles:** 

**protons(nucleus): +**     

**neutron(nucleus): ~** 

**electrons(orbitals): -** 

Energy levels in an atom

**2 electrons in first orbital, 8 in second**

isotopes vs ions

**isotopes: atoms with dif # of neutrons, affects mass of an atom**    

**ions: atoms that have gained or lost 1 or more electrons, affects charge of atom,**

**(lose= more pos charges than neg , gain=more neg than pos)**

Types of covalent bonds

**when atoms are covalently bonded tg= molecule**

Types of ions: anion (-) vs. cation(+)

**neg charge= anion**      

**pos charge= cation**

pH

**scale: measure of  the concentration of hydrogen ions in a solution**

**based on scale of 0-14, further away from 7=higher concentration**

acid/base

**7=neutral, below 7= acidic, above 7=base**

enzymes

**speeds up chemical reactions by reducing activation energy**

activation energy

 **amount of energy needed to start a chemical reaction**