Bio exam

Two major types of nucleic acids

1.        DNA – double stranded

2.        RNA – single stranded

Chapter 1

Types of Evidence

Steps of scientific process

1.        Make an observation

2.        Formulate Question

3.        Study previous research

4.        Peer review

5.        Form scientific hypothesis

6.        Experimentation

7.        Draw conclusion

8.        Publication

9.        Find patterns

Hypothesis – testable and falsifiable explanation for scientific observation/question

Peer review – helps ensure scientific results are valid as well as accurate and fairly presented

Correlation = constisten relationship between 2 variables

Dependent variable = part of experiment being measured/observed (control grp)

Independent variable = part of experiment being changed (experimental grp)

Chapter 2

All living organisms have 5 properties defining as alive

1.        Grow

2.        Reproduce

3.        Maintain homestasis – maintain relatively constant internal env no matter environment change

4.        Sense and respond to stimuli (events invoke response)

5.        Obtain and use energy

Exceptions

1.        Mule cannot produce (offspring of fem horse and m donkey, sterile)

2.        Fire grows reproduces and uses energy but is not alive

If scientists found an alien specimen with only a few of these traits, would it be considered alive? Yes, but it depends on what traits it has.

Matter – anything that takes up space and has mass

All matter is made of elements – substances cannot be broken down

Atom – smallest unit of an element with property of an element (4 electrons on outermost shell)

Nucleus – dense core of an atom

Subatomic partles determine atom properties

1.        Electrons – negatively charged orbiting nucleus

2.        Neutrons – uncharged paritlce in nucleus (carbon has 6)

3.        Protons – positively charged in nucleus

Periodic table = organized by atomic number

1.        Number of protons

2.        Each element placed in order by atomic number

Carbon atoms

-              Properties = oxygen 65%, carbon 18%, hydrogen 10%, nitrogen 3%, calcium 1.5%, phosphorus 1%

-              Electrons = 6 electrons

-              atomic number = 6

hemogloblin = how we get oxygen

1.        Organic Molecules =  carbon-based backbone, at least one C-H bond

2.        Inorganic molecules = no carbon based backbone, no C-H bond

Each macromolecules and their monomer

1.        Carbohydrates = gluclose/sugar

2.        Proteins  = amino acids

3.        Lipids = no true monomer

4.        Nucleic acids – nucleotides

Solvent = substance where another dissolve (water good)

Solute = dissolved substance

Solution = mixture solute and solvent

1.        Ionic bonds = strong bonds formed between oppositely charged ions

-               Water dissolves substances containing ionic bonds

2.        Ions = charged atom b/c electron loss/gain

Ion = charged atom

-              If atom loses electron = positively charged ion

Ph Scale – any below 7 is acidic, ranges from 0 to 14

-              Ph =  measure of hydro ion concentration to solution

Chapter 3

Plant cell wall is made up of sugar/cellulose

Cell theory –  all living things are made of cells and new cells come from dividing preexisting cell

Prokaryotic cell = no nucleus nor membrane bound organelles

Eukaryotic cells = nucleus

Similarities

-              Cell membrane has phospholipods amd proteins

-              Every cell has DNA

-              Cytoplasm: gelatinous aqueous interior

-              Ribosomes: complex of RNA and protein that carry out protein synthesis

Differences

Only eukaryotic cells

-              Nucleus

-              Many organelles

Only prokaryotic cells

-              DNA floating freely in cytoplasm

-              No organelles

-              Cell wall made of peptidoglycan, rigid structure enclosing cell membrane

Semi permeable cell (not all molecules can pass, small uncharged substances can cross via diffusion)

Cell membrane

1.        All cells have membrane

2.        Antibiotics must cross ccell membrane > effect

Endoplasmic Reticulum (ER)

-              Network of membrane covered “pipes”

-              Proteins and lipids synthesized here

-              Rough ER – bunch of little ribosomes to specific part

-              Smooth ER – no ribosome connected to specific part

Phospholipids – primary component of cell membranes, hydrophobic and partly hydrophilic structure

Golgi apparatus = receives proteins from ER (endoplasmic reticulum) via vesicles, packages and transports proteins

Mitochondria – extract energy from food, convert energy into useful form cells use

Chloroplasts – capture and converse sunlight energy to usable form

Lysosomes – digestive enzymes, break down worn out cell parts and food molecules

Cytoskeleton – protein fibers, functions = cell support, cell movement, movement of structures within cells

Endosymbiosis theory = free living prok cells engulfed other of the same cells billions of yrs ago > form mitochondria and chloroplasts