biology 1 - 2nd quarter reviewer

8/3/2019 Biology 1 - 2nd Quarter Reviewer

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BIOLOGY 12nd Quarter

Origin of LifeCore Concept 1: Spontaneous

Generation

Spontaneous Generationstates that life can arise

from nonliving matter

o John Needham proposed SG in mid-

1700s.

Heated a beaker fullof gravy with a cork.

Maggots appeared. DISCLAIMER: Beaker

may not have been

heated enough.

Core Concept 2: Biogenesis

Biogenesis states that lifecomes from only lifeo Fransesco Redi proposed

SG in 1668, Italian

physician.

Had both covered anduncovered jars.

Maggots appeared inthe uncovered jars.

Maggots did not

appear in the covered

jars.

Proved that maggotsform only when flies

come in contact with

meat.

o Lazzaro Spallanzanidecided to improve

Needhams experiment.

Boiled to flasks ofgravy.

Sealed one flask anddid not seal the

other.

Microorganismsappeared in the

unsealed one.

Proved that themicroorganisms

produced were

offspring of the

microorganism thatentered the flask.

o Louis Pasteur decidedto settle the argument

between B and SG in the

mid-1800s.

Designed a flask witha long curved neck

for boiled broth.

Microorganisms in theair did not make it

through the curved

neck.

Proved that thebroth remained free

of organisms as long

as it has no contact

with the

microorganisms in the

air.

History of the Eartho 4.6 BYA

temp, volcanicactivity, earthquakes,

meteor showers


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Early atmosphereH20, CO, CO2, H2,

N2, NH3, CH4

o 3.5 BYA Earliest evidence of

microfossils outlines

of ancient

prokaryotes, similar

to modern bacteria

First cells:prokaryotes,

heterotrophs,

anaerobeso 1,5 BYA

First eukaryoteso 650 MYA

First multicellularorganisms

o Trends in Evolution Cells: unicellular

multicellular

Nutrition:heterotrophs

autotrophs

Reproduction: asexual sexual

Core Concept 3: 4-Stage Chemical

Evolution

1. Abiotic synthesis of organicmonomers

1920s Oparin andHaldene: Conditions on

primitive Earth favored

chemical equations that

synthesized organic

compounds from inorganic

compounds

1953 Miller and Urey:Demostrated Abiotic

Synthesis of amino acids

and other organic

compounds found in living

organisms today

2. Abiotic synthesis of polymers Fox: Produced proteinoids

from clay and organic

monomers

3. Abiotic synthesis ofprotobionts

Ability to maintain aninternal chemical

environment differentfrom the surroundings

4. Origin of Genetic Info First genes may have

been abiotically produced

RNA

1968 Francis Crick andLeslie Orgel: RNA is lifes

first information storage

system

G. Cairns-Smith and K.Bernal: Amino Acids and

nucleotides stick to

repeating structures of

clay crystals

Cell Theory Anton van Leeuwenhoek

made first microscope

Robert Hooke coinedthe term cell

Robert Browndiscovered the nucleus

Matthias SchleidenAllplants are made of cells.


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Theodor SchwannAllanimals are made of

cells.

Rudolf VirchowAllcells arise from pre-

existing cells.

1. All living things are made ofcells.

2. Cells are the basic units oflife.

3. Cells come only from othercells.

Cell Structure and Function Three Basic Structures:

o Cell Membraneo Nucleuso Cytoplasm

Organelleso Cell Membrane lipid

bilayer that surrounds

the cell and regulates

entry or exit of

substances

Middle Lamella Primary Cell Wall Secondary Cell Wallo Cell wall protects and

supports the cell

o Nucleus contains DNA,information control

center

Nucleolus Nuclear Envelope Chromosomeso Cytoplasm area

between nucleus and cell

membrane

o Ribosomes site ofprotein synthesis

o ER assembly ofcomponents of CM and

storage of enzymes and

chemicals

o Golgi Apparatusprotein/molecule

modification, packing,

distribution

o Chloroplast site ofphotosynthesis

o Vacuoles storesmaterials

o Mitochondria site ofcellular respiration

o Nucleus contains DNA,information control

center

Nucleolus Nuclear Envelope Chromosomeso Cytoskeleton supports

cell structure and cell

movement

o Flagella drives cellmovement

Protein Factories: Ribosomes

Manufacturers and Shippers: ER &

GA

Clean-up Crew: Lysosomes

Storage Tanks Vacuoles

Power Stations: Mitochondria &

Chloroplasts

Framework: Cytoskeleton

Microscopy


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Microscopy study ofobjects or organisms too

small to be seen by the

naked eye

Microscope aninstrument that gives

enlarged images of the

object under study

o Compoundmicroscope

o ElectronMicroscope

Compound microscopetwo-way lens system;

concave brighter, plane

darker

Computationso Theoretical

magnification =

ocular x objective

o Diameter = (LPOdiam)(LPO mag)

= (HPO

diam)(HPO mag)

o Cell sizediamter / # of

cells spanning the

diameter

Parts of the microscope:o Eyepieceo LPOo HPOo Stageo Baseo Fine Focuso Coarse

Adjustment Knob

oNeck

o Iris Diaphragm

o Mirroro Stage clipso Revolving

nosepiece

o IlluminatorThe Biology of DiseaseCore Concept 1: Disease

Disease any change thatinterferes with the

normal functioning of the

body

Core Concept 2: Germ Theory ofDisease

Germ Theory of Diseasean infectious disease is

caused by a certain

disease

o Robert KochGerman

Bacteriologist

o Louis PasteurFrench Chemist

Core Concept 3: Pathogens

Pathogen microorganismcausing a certain disease;

can destroy body cells

and tissues; can produce

poisons/toxins that kill

cells or interfere with

their functions

o Viruses non-cellular particles

invading living

cells; causes

AIDS, polio,

smallpox, measles,

colds, etc.


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o Bacteriaunicellular

prokaryotes;

causes pneumonia,

strep throat,

acne,

tuberculosis,

cholera

o Protists anyeukaryote that is

NOT a plant, an

animal or a

fungus; causesmalaria, amoebic

dysentery

o Fungieukaryotic

heterotrophs

with chitinous

CWs; causes

ringworm,

athletes foot,

histoplasmosis

o Worms parasiticanimals; causes

tapeworm,

schistomiasis

Infectious Diseasedisease caused by the

entrance of a

microorganism to the

body

Core Concept 4: Kochs Postulates

Kochs Postulates set ofrules that is used to find a

specific pathogen causing a

disease

oThemicroorganism

must be found in

abundance in all

organisms

suffering from

the disease, but

should not be

found in healthy

organisms.

o Themicroorganism

must be isolated

from a diseased

organism andgrown in pure

culture.

o The culturedmicroorganism

should cause

disease when

introduced into a

healthy organism.

o Themicroorganism

must be

reisolated from

the inoculated,

diseased

experimental host

and identified as

being identical to

the original

specific causative

agent.

Lyme Diseaseo Who: Allen

Steere of Yale

University


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o Where: town ofLyme, state of

Connecticut

o Observations: 39 children +

several adults

Similar tojuvenile

arthritis

Started insummer or

early fall;

began as aninsect bite

followed by

expanding skin

rash

Kochs Postulate 1o Skin rash linked to

the bite of a deer

tick

o Found spiral-shapedbacterium in the

ticks, Borrelia

burgodorferi

o Steere found B.burgodferi in

patients with

Lyme disease.

o HYPOTHESIS: B.burgdorferi causes

Lyme disease

Kochs Postulate 2o B. Burgdorferi was

grown in pure

culture

Kochs Postulate 3o

B. Burgdorferi wasinjected onto mice,

and developed

similar symptoms

to those of

children

Kochs Postulate 4o Steere recovered

B. burgdorferi

from sick mice

CONCLUSION: B.burgdorferi is thepathogen causingLyme disease

Core Concept 5: Modes of Infection Food and Water-borne

tapeworms, amoebasis

Airborne droplets ofpathogens expelled into

the air

Contact common colds,STDs

Carriers/Vectorsmosquitoes, tsetse fly

o Vector anorganism that

transmits a

certain disease

VirusesDiscovery of Viruses

Tobacco Mosaic Diseasedisease of the plants causing

it to have patch-like

patterns

Adolf Meyer tried to findthe cause of Tobacco Mosaic

Disease; stated that the

bacteria is too small to be

seen even under themicroscope


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Dmitri Ivanowsky statedthat the bacteria is so small,

it could penetrate the filter

or it produces toxin that is

able to pass through the

filter

Martinus Beijerinckdisproved Ivanowskis

conclusion; stated that the

infectious agent is capable of

reproduction and much

smaller and simpler than

bacteria Wendell Stanley stated

that a virus can only

reproduce in its host, cannot

be killed by bacteria and is

much smaller and simpler

than bacteria

Definition and Structure of the

Virus

Virus non-cellular particlesmade of genetic material

that invade living cells

Virion complete virusparticle

Structure of a Virus:o Nucleic Acid Core

contains virus genetic

material

o Capsid protein coatsurrounding the nucleic

acid

o Lipid Envelope lipidbilayer of the virus that

may conatin spikes

Shape of a Virus:(determined by its capsid ornucleic acid)

o Polyhedralo Helicalo Binal

Structure of Bacteriophages:o Head contains DNA

molecule

o Tail used to inject theviral DNA into the host

cell

o Tail Fibers used toattach to host

o Bacteriphage bacteria-eaters

o Nucleic Acid SNA orRNA, but not both

o Internal protein Properties of Viruses

o Non-livingo Non-cellularo Can only reproduce in

host cell

o Cause many commonillnesses

o Ubiquitous Alive when in a host cell,

considered dormant and

dies when not in a cell

Virus Classification

Viruses may have:(depends on the nature

and function of the virus)

o Double-stranded RNAo Double-stranded DNAo Single-stranded DNA, oro Single-stranded RNA

Size 5 to 300 nm Host specificity depends

on:


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o Specific attachment siteson the host cells called

receptors

o Availability of cellularfactors required for viral

multiplication in the host

cells

Vaccination and Gene Therapy

Vaccination discovered byEdward Jenner; exposing

the body to a milder

version of a virus may help

it modify for a strongersickness.

Gene Therapy processused to cure genetic

diseases where modified

viruses are injected into a

person and goes to the

defective part of the DNA

and attaches itself there

so it can replace it with

healthier ones.

Origin of Viruses:

Scientist cant find theorigin because:

o Viruses do not formfossils

Three Main Hypotheses:o Progressive: Hypothesis in

which a membrane of a

cell exits it and enters

another

o Regressive: Hypothesis inwhich viruses were once

complex until their

parasitism caused them

to lose genetic

information not related

to parasitism

o Virus-First: Hypothesis inwhich viruses were the

first organisms on Earth

and they led to the

formation of the 3

domains of life

Virus Reproduction

Lyctic Cycle culminatesin the death of a host cell

o Attachmento Penetrationo Synthesis of Viral

Genomes

o Assemblyo Release

Lysogenic Cyclereproduction without

destroying the host

o Attachmento Penetrationo Prophageo Reproductiono Spontaneous Induction

biology 1 - 2nd quarter reviewer

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