BIO exam 1

Natural science

The field of science that is related to the physical world and its phenomena and processes.

-composed of physical and life science

Physical sciences

Astronomy, chemistry: study of nonliving matter

Life science

Biology, etc: study of living things

Biology

the study of life: the study of living organisms and their interactions with one another and their environments

Basic (Pure science)

science done simply to gain knowledge, regardless of application

applied science (technology)

science applied to real world problems

Discovery science

Inductive/descriptive: Describes natural structures and processes as accurately as possible through careful observation and analysis of data. Scientists derive generalizations based on a large number of specific observations

Hypothesis based science

deductive: Inquiry that asks specific questions and tests a hypothesis: a tentative answer to a well-framed question or observation; an explanation on trial.

Hypothesis

Must be testable and falsifiable.

Null Hypothesis

It assumes there is no relationship between the two variables and that controlling one variable has no effect on the others

scientific method

1. Make observations

2. Develop hypothesis

3. Design experiment

4. Collect data

5. Analyze data; do my results confirm my hypothesis?

6. Refine and repeat experiment

7. Communicate results

Independent variable

the factor or element that you, as the researcher, can change, manipulate, or control in an experiment or study to observe its effect on something else, known as the dependent variable

Dependent variable

A dependent variable is what changes as a result of the independent variable manipulation in experiments. It's what you're interested in measuring, and it “depends” on your independent variable.

controlled variable

any factor in a scientific experiment that is held constant and unchanged throughout the study to ensure that only the manipulated independent variable is affecting the dependent variable, leading to more accurate and reliable results.

constant variables

a value that is fixed and does not change during an experiment or in a programming context.

Inductive reasoning

uses related observations to arrive at a general conclusion 

Deductive reasoning

form logical thinking that uses a general principle or law to forecast specific results, from which a scientist can extrapolate and predict the results

serendipity

fortunate accidents/ lucky surprises that lead to scientific breakthroughs 

scientific theories

• a hypothesis that has been repeatedly tested and not yet falsified 

• Broad in scope and supported by a LARGE body of evidence

• Universally accepted among scientists however, they can still be disproven

• Constantly being challenged, tested, and modified as new information is obtained (and this is where their strengths are!)

Properties of life

1. Order

2. sensitivity or response to stimuli

3. reproduction

4. growth and development

5. regulation/homeostasis

6. evolution/adaptation

7. energy processing

Animal cells vs Plant cells

Animal Cells have centrioles and lysosomes, plant cells don’t.

Plant cells have chloroplasts and a large central vacuole, animal cells don’t.

Prokaryotes vs Eukaryotes Chromosomes

Prokaryotes have circular chromosome structure.

Eukaryotes have linear chromosome structure.

Prokaryotes vs Eukaryotes Organelles

Prokaryotes have no organelles. Eukaryotes do.

Prokaryotes vs Eukaryotes Ribosomes

Both Prokaryotes and Eukaryotes have ribosomes.

Prokaryotes vs Eukaroytes reproduction

Prokaryotes reproduce via binary fission.

Eukaryotes reproduce via mitosis/meiosis.

Prokaryotes vs Eukaryotes size

Prokaryotes are much smaller (0.1um-5um)

Eukaryotes are much larger (10um-100um)

Prokaryotes vs Eukaryotes age

Prokaryotes 3.5 BYA

Eukaryotes 1.5 BYA

Prokaryotes vs Eukaryotes plasma membrane

Both have plasma membranes.

Shared Characteristics between Prokaryotes and Eukaryotes

Both have chromosomes, ribosomes, and plasma membrane.

Taxonomy

Branch of biology that names and classifies species

Phylogeny

branch of biology dividing evolutionary history and relationship of an organism and groups of organisms

Order of Taxonomy and Phylogeny

Life, Domain, Kingdom, Phylum, class, order, family, genus, species (Dear king Phillip came over for good soup)

Evolution

Descent with modification

Lamarck’s theory of evolution

inheritance of acquired characteristics (proven false)

Darwin and Wallace’s theory of evolution

natural selection and survival of the fittest

Relative fitness

survival and reproductive rate of a trait relative to the total survival and reproductive trait of other traits in the population

Fitness

survival, finding/maintaining mates, number of health and fertile offspring

Complexity of life

Atom, Molecule, organelle, cell, tissue, organ, organ system, organism, population, community, ecosystem, biosphere 

Matter

anything that takes up space and has mass 

Most four common elements of living organisms

CHON

Other essential elements

Calcium, Phosphorus, Potassium, sulfur, Sodium, Chlorine, Magnesium

Atoms

basic unit of matter and composed of subatomic particles

-composed of protons, neutrons, electrons

Molecules

Two or more atoms chemically bound

Compounds

two ore more different elements chemically bound in a fixed ratio

atomic number

number of protons

mass number

sum of protons and neutrons

Isotopes

atoms that have the same number of protons but differ in the number of neutrons in the atomic nucleus

Radioactive isotopes

unstable and spontaneously give off particles 

How can isotopes be used

carbon dating, half life calculations nuclear power plants, medical applications, quality control, sterilization, academic research, density and moisture content elevation

Chemical properties

Elements in the same group have similar chemical properties and an atoms behavior is determined by its electron configuration and distribution (Valency)

Valence shell

8 electrons

Valency

the number of unpaird electrons

Valence electrons

number of electrons on the outermost shell

covalent bond

a strong bond that results for sharing a pair of valence electrons (nonmetal+ nonmetal)

Electronegativity

attraction of a particular kind of atoms for the electrons in a covalent bond

-based on # of protons, # of electrons, and atomic radius

Nonpolar covalent bonds

atoms have non polar electronegativities and share the electrons equally

polar covalent bonds

atoms have polar electronegativities and share electrons unequally, results in partial positive and negative charges and dipole moments

Ionic bonds

electron transfer between two atoms which creates ions 

cations- positive ions

anions- negative ions

weak chemical bonds

reinforce the shape of large molecules and allow for dynamic and reversible reactions

chemical reaction

leads to changes in the composition of matter, bonds are broken or formed

-can be reversible

Cohesion

the attraction between water molecules due to hydrogen bonds

-creates surface tension

What creates surface tension

cohesion

adhesion

the attraction of water moles uses to water molecules

-creates capillary action (Water flowing against gravity)

what causes capillary action

adhesion

What has the highest specific heat capacity of any liquid

water

water’s high heat capacity

high specific heat capacity causes land to cool faster than sea, and why warm blooded animals use water to disperse heat in bodies

Water’s heat of vaporization

allows water to act as a heat sink or heat reservoir 

(why land near bodies of water are cold)

-evaporation of sweat allows for cooling

Water’s states of matter

gas, liquid, solid

Solid Water

forms crystalline structure

water’s solvent properties

-universal solvent, providing a medium to dissolve more different materials than any other solvent

-interacts with ionic compounds through “sphere of hydration” / “hydration shells”

solute

substance that is dissolved

solvent

liquid which is dissolved in a solute

solution

mixture of a solute and a solvent

water’s polarity

water is a polar molecule

attraction of positive and negative charges

-water is attracted to other polar molecules 

Molarity

moles/liter

disassociation of water and the ph scale

water disassociates into ions which are very reaction, and changes in the concentration of these ions affect pH

pH

concentration of [H+] ions

-log[H+]

Neutral PH

[H+]=[OH-]

acidic

[H+]>[OH-]

Basic

[H+]<[OH-]

pH scale

0-6.999999= acidic

7=neutral

7+ = basic

pOH

-log[OH-]

[H+] * [OH-]

= 10^-14

Buffers

substances that minimize the changes in the concentration of H+ and OH- ions in a solution

-reduce pH change

-weak acid-base pair that reversibly combines with hydrogen ions

carbon

can form 4 covalent bonds bc of 4 valence electrons

-backbone of macromolecules

hydrocarbons

C+H

-Covalent bonds in hydrocarbons store energy

-Form Ring structures

Dopmaine

neurotransmitter containing a benzene ring

-part of the reward motivation pathway

Isomers

compounds that have the same number and types of atoms of an element, but are arranged differently

Structural isomers

differ in covalent arrangement, but have the same molecular formula.

-shape determines function

Geometric isomers

different in spatial arrangement around double bonds

cis- same side

trans- opposite side

Cis Isomer

Atoms are placed on the same side of the double bond

Trans isomer

atoms are placed on opposite sides of the double bond

Enantiomer

have four different groups bonded to an asymmetric carbon

(mirror images)

-important for molecular interactions and shape

Functional Groups Of Carbohydrates

Hydroxl, Carbonyl

Functional Groups of Proteins

Carboxyl, Amino, Sulfhydryl

Functional Groups of Nucleic acids

Methyl, Phosphate

Functional Groups of Lipids

Carboxyl

Functional groups

reactive parts of molecules/compounds

-help organic compounds dissolve in water (polar) and form hydrogen bonds

Hydroxyl

O-H

Carbonyl

C=O