BIOL300: Chapter 1

What is the cell theory?

Cells are the building blocks of all living tissues

cells are generated only from pre-existing cells and inherit their characteristics

What do all cells have in common?

The central dogma

How can we remember the central dogma?

information storage "the hard drive"

temporary message "the cache"

functional units "the programs"

Central Dogma order

1) DNA synthesis: replication

2) RNA synthesis: transcription

3) protein synthesis: translation

Our genes hold the code but what determines their function?

The expression of the genes determines function

nerve muscle cells can be

nearly 1 meter

if cells glow

they are alive

light microscope

allows us to magnify cells up to 1000 times and resolve details as small as 0.2 micro meters

confocal microscopy

uses laser beams to scan the object and make an image

transmission electron microscopy

Uses a beam of electrons to pass through an object and project an image

prokaryotes

small single cellular organisms

first to evolve

most diverse of all cells and can adpat to extreme environments

two domains: bacteria or archaea

many different sources of 'food': oxygen, hydrogen, sulfur, some are even photosynthetic

eukaryotes

bigger, more elaborate

can be single-celled or multi-cellular

always have a nucleus, organized, compartmentalized (membrane bound)

organelles conserved in most

Yeast is the most simple type of___

eukaryote

whats inside the cell?

tighly packed fluid environment that is constantly moving, changing and refreshing

why is separation important in cells?

some things aren't compatible which is why membrane bound is so important

nucleus

government

where DNA is stored

why a nuclear membrane?

to physically separate the cell's genetic material (DNA) from the cytoplasm,

ribosomes

most common organelle

not membrane bound

help create protein

comprised of 80-90 molecules that catalyze translation; they make all the new proteins needed to keep the city working

mitochondria

make ATP

most abundant organelle

oxidate food molecules to generate ATP (cellular respiration)

contain their own DNA and reproduce themselves (like bacteria)

mitochondria and chloroplasts are...

endosymbionts

eukaryotes likely evolved as a predator because they

- have large flexible membrane

- have cytoskeleton for movement: which allows eating

- have a nuclear compartment that may have evolved to protect valuable genetic material from chaos of cytoplasm

chloroplasts

green organelles found in plants and algae

important for generating energy

It is also an endosymbiont

endoplasmic reticulum

"highway" of the cell

found outside the nucleus

moves proteins

rough endoplasmic reticulum

coated with ribosomes to secrete protiens

smooth endoplasmic reticulum

involved in lipid synthesis

golgi apparatus

post office

takes proteins and separates them to different locations of the cell

lysosomes

waste disposal system

tummy of the cell; has low pH

house intracellular degradtion

breaks down food and releases back to cell

break down waste for recycling or excretion (digestive enzymes)

peroxisomes

chemical plant

small, membrane enclosed vesicles

contained environment for H2O2 reactions.

H2O2 generated and degraded inside

the peroxisomes membrane enclosed vesicles allow

a protected place to create and break down H2O2

cytoskeleton

really important to help cells move around

allows buildment of our cells

are not static

help gets work done

Escherichia Coli (E. Coli)

single cell, has circular double stranded DNA, ~4.6 million nucleotide pairs long

prokaryote and bacteria

produces 4300 different kinds of proteins

Saccharomyces cerevisiae (yeast)

minimal model eukaryote

single cell

has nucleus

can study the structure of an organism

arabidopsis thaliana (plant)

complete DNA sequence is known

grows in 8-10 weeks

produces a lot of offspring

drosophila melanogaster (fruit fly)

we know the XY chromosomes and how genes interact because of this organism

shows us how to trace cause and effect from DNA instruction to structure of adult multicellular organism

caenorhabditis elegans (c. elegance)

only creature that has its neurons fully mapped

brain is very tiny and has 959 body cells

we know its functionality

used to study the effect of alcohol on the brain

danio rerio (zebra fish)

transparent for the first two weeks of life

works well in lab and only need around 8 fish

excellent for developmental studies

Mus Musculus (mice and rats)

can be used study social interactions

genetic and physiological similar to humans

homo sapiens (humans)

incredibly social creatures

can be model organisms

testing of drugs on humans is required by FDA before it can be released

cell culture

done at the cellular level

cell grown in plates in the lab

primary cell culture

isolated directly from the live organism

limited lifespan (hayflick limit)

immortalized cell line

transformed cells that can grow indefinitely; like cancer

continue to grow and divide rapidly. they are not isolated from the live organism

limitation: they don't do their jobs

What are some uses of immortalized cell lines?

study cell behavior

response to drugs and the environment

industrial products (proteins and antibodies)

Can viruses carry out the central dogma on their own?

No, they must have a host

True or False: Viruses can replicate without a host.

FALSE

What is the plasma membrane made out of?

proteins and lipids

The phospholipids in the plasma membrane are__

amphipathic (they have both polar and nonpolar regions)