370 CELL TYPES/STRUCTURES (2.1)

Living things common attributes (3)

-CATALYSIS: extract energy from nutrients
-MUTABILITY: respond to changes in environment
-REPLICATION: ability to grow, differentiate and reproduce

Prokaryotes

-NUCLEOID: DNA material inside, floats freely in cytoplasm, one large circular chromosome
-PLASMID: small circular DNA molecules
-NO organelles, vesicles
-Unicellular
-Flegella (motion structures)
-Asexual duplication (binary/multiple fission)

Eukaryotes

-Has organelles, compartmentalized
-More genetic information than prokaryotes
-Larger than prokaryotes
-Discrete number of linear chromosomes
-Duplicate via mitosis/meiosis

Cytoplasmic Membrane

-Double layer of lipids that seperates cell interior and outside environment
-Proteins control what can enter/exit the cell
-Prevents leakage
-Site for many proteins

Nucleus

Nucleus—genetic material, site of ribosome synthesis, chromatin ( DNA wrapped around proteins) stored in nucleoplasm

Nuclear pores—small channels that let substances enter/exit

Nucleolus—where new ribosomes are assembled

Ribosomes

-Protein factory
-Made of RNA and proteins

Mitochondria

-Site of aerobic respiration
-Contains an inner membrane
—Innermost space contains soluble enzymes involved in aerobic respiration
-O2 used as electron acceptor

Endoplasmic Reticulum

-Modify proteins

-Synthesize lipids

ROUGH ER—studded with ribosomes that synthesize secreted proteins
SMOOTH ER—synthesize carbohydrates, lipids, steroid hormones, detoxification of medication/poisons

Ribosomes make proteins → feed protein chains to RER → proteins fold and undergo modifications (EX: adding carbohydrate side chains)

Golgi Apparatus

-Secreted proteins and lipids go from ER to GA
-Recieves, processes, produces vesicles (packages containing biological molecules, surrounded by a membrane)
-Final assembly and packaging unit
-Secreted proteins/lipids go through a series of modifications (EX: adding carbohydrates)

Prokaryote Eukaryote SIMILARITIES

-Cytoplasmic membrane

-Ribosomes translate mRNA into proteins
-Genetic material stored as DNA

Autotrophs

Doesn’t get energy from organic molecules

PHOTOAUTOTROPHS—uses solar energy

CHEMOLITHOTROPHS—redox reactions

Heterotrophs

Extracts energy from pre-existing organic molecules

Obligate anaerobes

O2 is toxic

Obligate aerobes

must use O2

Facultative anaerobes

Can grow in presence or absence of O2

Bacteria in biotech applications

-Rapid growth

-Easy to introduce foreign DNA

-Can select strains of interest

APPLIED IN: food products, thickening agents, nucleic acids, recombinant proteins, activated sludge
EX: ecoli

Fungi in biotech applications

-Produces metabolic by-products (ethanol, carbohydrates, amino acids, polymers)

APPLICATION: food industry, thickening agents, antibiotics
EX: Bacillus

Animal cells in biotech applications

-Recombinant proteins that require complex modifications are easier to produce with animal cells
-Slow, fragile, expensive

APPLICATION: antibodies used for chemo, cytokines used to modulate immune systems, vaccines
EX: Chinese hamster ovary cells