BIOL 100 UNLV Exam 1 Study Guide

Characteristic of a living organism

1: composed of cells

2: Unique molecular composition

3.responds to external environment

4.maintain homeostasis

5.requires energy and raw materials

6.grows and reproduces

7.populations are capable of adapting and evolving

Levels of Biological organization

Atoms, molecules, cell, tissue, , Organ, organ system,organism, population, community, ecosystem, Biosphere

A M C T O O O P C E B

Organ

Made up of different tissues working together

Population

all individuals of a particular type of species or organism that ay interact in a particular place

Community

all different types of organisms that may interact in a particular place

a scientific approach to classify by relatedness (linen taxonomy)

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species. EX: Dumb Kids Play Catch On Freeway Get Smashed

Characterizing the 3 domains of life

Bacteria

Archea

Eukarya

Domains Bacteria and Archea

Genetically very different

But both are unicellular and both have prokaryotic cell structure

Eukarya

Unicellular and multicellular

Complex cell structure(Eukaryotic)

Many membrane bound organelles

Eukaryotic kingdoms

Protists

Fungi

Plants

Animal

Categorizing the brown bear (Ursas Arctos)

Eukarya

animilia

chordata

mammailia

carnivora

urisdae

ursus

arctos

are viruses alive

No they are not alive

-It is not a cell

-can have a protein coat or take on parts of the membrane of a host cell

-contains some genetic material, but not enough to replicate

Viruses infect other organisms and then use that organisms cellular machinery to replicate

Human taxonomy

Eukarya

Animalia

chordata

Mammal

Hominade

Homo

Sapiens

Members of the Hominidae

Mountain Gorilla

chimpanzee

Bonobo

Lowland Gorilla

Sumatran orangutan

Bornea Orangutan

Biology

Life is defined by the characteristics of life

Life can be organized in many ways

Icreasing complexity

bio levels of organization

genetic relatedness

Linean Taxonomy

Science

science is a process, a logical method of understanding the natural world

Theory

In science a theory is a collection of principles supported by evidence, that explains some aspect or phenomena or NATURE

Science Method

-Based on observations and measurements

-from observations come questions

-From questions, formulate a "hypothesis"

Hypothesis

-Plausible explanation of natural phenomena

-often formally written in a way which the explanation could be found to be incorrect

-thus science has an underpinning of skepticism

scientific method

A statement is scientific if an objective method can be stated by which it can be disproven

Testable

refutable

repeatable

Test validity

is the extent to which a test (such as a chemical, physical, or scholastic test) accurately measures what it is supposed to measure.

Example:Oatmeal and cholesterol

Louis Pasteur's test of the spontaneous generation of life

Based on observations, people in the early

1800s believed that life regularly arose from the coming together of chemicals

• Pasteur's hypothesis: Cases of spontaneous generation of life could be explained by microscopic airborne organisms

psudeoscience

often referred to as "Junkscience"

• Presented as scientifically valid but not in fact scientific

• Unstable

• Lack empirical support

• Based on faulty reasoning

• Poor methodology

Biological Molecules

carbohydrates

lipids

proteins

nucleic acids

Carbohydrates

sugars and starches

our energy source

Carbon

forms up to 4 covalent bonds

the energy source of life

simple carbohydrates

simple sugars

monosaccharides = 1 sugar (glucose)

Dissacharides = 2 sugars (sucrose)

Complex Carbohydrates

Polysaccharides (starch)

Made up of simple units of repeating units of simple sugars called monomers

in plants the storage polysaccharides is starch and in animals its glycogen

Dehydration Synthesis

Polymers form through dehydration synthesis

the reaction that bonds one monomer covalently to another will release a water molecule: one monomer will donate OH and the other will donate H

2 monomers will make a polymer

Hydrolysis

used to break apart a polymer

requires the addition of water

will result in two monomers

Lipids(fats)

compounds that do not dissolve in water

non-polar(having no electrical charges)

HIGH RATIO of hydrogen relative to oxygen

Major uses:

o Energy

o Energy storage

o Insulation: poor conductor of heat

o Protection

o Cellular structure and function

Fatty Acids

• Carboxyl functional group

• Saturated Fatty Acid: only single covalent bonds linking the carbon atoms

• Unsaturated Fatty Acids:Double bonds between carbons change physical shape of the molecule, thus its behavior

triglyceride

3 fatty acids, bound to glycerol(an alcohol)

most common fat used in food

proteins

molecules that facilitate biological functions

a polymer made up of one or more chains of amino acid

-generally large chains and a complex structure

peptide

chains containing only a few amino acids

large molecule

amino acids

building blocks of peptides and proteins

-20 different ones

-will vary in side chain

2 main types: essential (obtained by humans through food) and nonessential (synthesized in the body)

polypeptide

small chains of amino acids

containing 10 or more amino acids

protein

a polymer made up of one or more chains of amino acid

-generally large chains and a complex structure

proteins different types and functions

Enzymes: quicken chemical reactions

transport : move other molecules

communication: cell to cell signaling

contractile: muscle movements

structural: physical/mechanical support

protective: defend against invaders/cancer

protein structure

primary: specific sequence of amino acids

secondary: bending and coiling of the chain

tertiary: 3D folding produces shape

Quaternary: consist of two or more polypeptide chains

.Enzymes

proteins that speed up chemical reactions

very specific in they activity

Example lactose --> lactase

nucleotides

small molecule important for (contains nitrogen)

1) energy transfer in cells

2) store and transmission of genetic information

small units will make up dna and rna

Cellular energy transfer

breaking and forming of bonds in ATP= release and storage of energy

ATP: adenosine triphosphate (3 phosphates): Energy currency of cells

ADP: Adenosine diphosphate (2 phosphates): uses energy from food and sunlight, and makes energy available for cellular work and chemical synthesis.

nucleotides used in genetic information

DNA made of nucleotides, "bases"

Adenine

guanidine

cytosine

thymine

the sequence of bases determines amino acids in proteins

A=T`

C=G

EXP: A C G

T G C

ATP

consists of the sugar ribose

the base adenine

and 3 phosphate groups

formed from ADP

energy currency of cells

Cells

Smallest Unit of Life

Prokaryotes

DNA is dispersed in the cell

very small

always single celled

few organelles

Eukaryotes

DNA in nucleus

100x larger

multi cellular

Animal cells

"Typical" animals cells:

filled with fluid, surrounded and linked to other cells, and immerse in a watery fluid

Everything going in/out must pass through the cell membrane

Cell size

small in size

surface to volume ratio

as volume increases surface area slowly falls behind.

SA: H*W* # of sides

Volume: H*W*Length

Plasma Membrane

regulates the movement of substances into and out of the cell

maintains structural integrity

selectivelypermeable

cell to cell recognition

communication between cells

cell adhesion: bonding pairs of groups of cells together to form tissues and organs

Phospholipid Bilayer (main structural component)

see figure 3.6

functions of the plasma membrane

regulation of thing going in and out the cell

cell recognition using glycoprotein

cell-cell communication

cell-cell adhesion

Movement across the cell membrane:

Simple diffusion

movement of a SOLUTE from high to low concentration

Osmosis

Movement of WATER from high to low concentration

Facilitated Diffusion

Move from high to low concentration using transport proteins

hypertonic

solute concentration is higher than that inside the bag

more water moves out than in causing the bag to shrivel

isotonic

one with the same solute concentration as inside the bag

no net movement in either direction

hypotonic

the concentration of solute is lower than that inside the bag

causing swelling and could possibly burst.

Active transport

across the membrane from low to high concentration with the help of a carrier protein

requires energy

protein pumps use energy to move stuff

ex) cells contain higher ca+ than surrounding fluids.

Endocytosis

...Large molecules(single celled organisms such as bacteria) enter the cell through endocytosis

A region of the plasma membrane engulfs the substance to be ingested and then pinches off from the rest of the membrane

enclosing the substance in a sac like structure called a vesicle

the vesicle then travels through the cytoplasm

Two types of this are Phagocytosis(cell eating; engulfing bacteria) and pinocytosis(pinching to form vesicle)

Exocytosis

...The process by which large molecules leave cells

when he vesicle reaches the plasma membrane, the vesicle membrane will fuse with the plasma membrane

Then the vesicle opens up to release the hormones outside

the cell

nerve cells also release chemicals during this process

ideas of selective permeability in the membrane

smooth ER

...Lacks ribosomes

detoxifies alcohol and drugs & makes phospholipids

plasma Membrane

Nucleus

...contains most genetic info/bound nuclear membrane

produces rNA ribosome carry genetic code protein

surrounded by the nuclear envelope

Rough ER

...network of channels connected to nuclear envelope & is studded with ribosomes. Sightof protein synthesis

Golgi complex

receives proteins, conducts further processing, sorting, and packaging

lysosome

...enzyme filled vesicles (from Golgi complex)

conduct intercellular digestion

Mitochondria

-extracts energy from the breakdown of energy rich molecules for use in cells

-contains its own genetic information and ribosome

-can make its own proteins

-PROVIDE CELL WITH ENERGY THROUGH THE BREAKDOWN OF GLUCOSE DURING CELLULAR RESPIRATION

Cytoskeleton

Controls how things move, cell shape, and the movement of things within the cell

Composed of three distinct filament types: intermediate filaments, microtubules, and microfilaments

how cells get energy from food

Digest :macromolecules from food into simpler components (glucose)

Absorb energy rich molecules into bloodstream and carries to the cell

Extract Energy

Photosynthesis formula

Ultimelty the energy used by the vast majority of organisms for growth survival reproduction come from the sun

carbon dioxide---> water--> Photosynthesis--> glucose---> oxygen gas

cellular respiration formula

6O2 + C6 H12 O6-->ATP--> 6H2O + 6CO2

Glucose+oxygen---> E(ATP)+Carbon dioxide2+water

Energy

Capacity to bring about movement against the opposite force

Potential: stored energy

Kinetic: energy in motion

Cellular respiration

cells derive from the breakdown of energy rich molecules like glucose

1. glycolysis

2.tranisition reaction

3.citric acid cycle

4.Electron transport chain

Glycolysis

occurs in cytoplasm and doesn't require oxygen

splitting requires 2 ATP to break glucose

But will make 4 ATP (net gain 2 ATP)

splits glucose into two making two pyruvates

plus makes 2 NADH (Electron career molecule)

Electron carrier NADH

Carries energy rich electrons to the electron transport chain

Transition Reaction

produces:

1 Co2

1NADH

1 Acetyl CoA

pyruvates are moved to mitochondria and prepared for processing for the citric acid cycle

Citric acid cycle

completes the breakdown of glucose

Produces

2CO2

1ATP

3NADH

1 FADH2

All carbon from original glucose now gone

Electron Transport Chain

Electrons delivered by NADH and FADH2 are used tops H+ ions up the gradient

Electrons then flow down the gradient through carrier proteins imbed in the inner membrane to make 32 ATP made for glucose

The low energy electrons are. eventually given to oxygen and water

Cellular respiration All together...

the 4 steps produce36 molecules ofATP per each molecule together

Oxygen is required for cellular respiration...

without oxygen, there is nothing to accept the low energy electrons...electrons shuttles can't release their electrons

this blocking ETC CAC TR

Fermentation

anaerobic respiration

breakdown of glucose without oxygen

glycolysis is modified

pyruvateor a pyruvate derivative accept the energy electrons and produce2molecules f ATP

pyruvates act as a final electron recipient

Matter

Physical substance that takes up space and has mass

3 Basic states of Matter

o Solid, liquid, gas, plasma

o How do these states differ: in how much space the matter takes up (volume&density)

Element

pure form of matter containing only one kind of atom

ATOM

• smallest particle of an element

o An atom can't be broken down by ordinary chemical processes

o Something like 118 elements but earth is made up of less than 100 elements...around 94-95

Subatomic particles

makes up the atom (protons neutrons electrons)

Protons

positive charge...has mass...used to determine identity

Nuetrons

No charge...has mass...numbers can change

Electrons

Negative charge...mass is negligible...number can change

Atoms

• are extremely small

o mostly empty space

o nucleus makes up only a tiny volume even though it contains less than 99.9% of mass

o Nucleus contains the mass

Elemental composition of Organism

o only 6 elements makes up 98 percent of living organism

o we are 69% of water

o carbon,

o hydrogen,

o nitrogen,

o oxygen

o phosphorus

o Sulphur

number of elements important to life

25

Atomic number

# of protons

Atomic Mass

protons and neutrons

Atomic weight

average number

Isotopes

Isotopes

• Atoms of a particular element all have same number of protons, but they can differ in number of neutrons

• Example: Carbon

• Carbon-12:stable

• carbon-13: stable

• carbond-14: Unstable(radioactive)