ch.4 - eukaryotes

Four Eukaryotic Kingdoms

Animalia: animals
Plantae: plants

Fungi: molds, yeasts, mushrooms

Protista: etc.

Shared ancestors for Bacteria, Eukaryotes and Archaea

Bacteria: peptidoglycan cell wall + 70s

Eukaryotes + Archaea: shared RNA

Eukaryotes: nucleus

External Structures: 3

Glycocalyx, Flagella, Cili

Glycocalyx

this instead of a cell wall

made of glycoproteins and polysaccharides too

function: attachment, protection from dehydration, comm. between cells, ahesion (same as capsules + s-layers for bacteria)

Flagella

used to thwip back and forth rather than rotate

made of microtubule pairs encased in cell membrane rather than parts

Cilli

short hairs that cover the cell and attach to stuff (ex: cilia in nose for mucus collection)

*ciliates on protists

Boundary: 2

Cell wall + Cell membrane

Cell Membrane

only ONE layer made of Phospholipid Bilayer for structure and selective permeability

Cell wall (what are they in?)

function: structure, prevent lysis, protection
not present in animals
plantae: cellulose
fungi: chitin (antibiotics dont work bc specialized cell wall)
protists: depends

What’s the benefit of having so many membrane enclosed organelles?

Different reactions can happen simultaneously in the same cell

Internal:

Cytoskeleton, Nucleus, ER, Golgi Apparatus, Lysosome, Peroxisome, Vacuole, Mitochondria, Chloroplast,

Cytoskeleton

protein structure to help cell move, transport organelles, and maintain shapes

made up of three filaments:

microtubules (cell structure),
microfilaments (muscle contraction)

intermediate filaments (protection vs environment)

Nucleus

double bilayer and nuclear pores to let stuff out + nucleus to make ribosomal parts
*DNA LIVES HERE

ER

smooth: lipids
rough: proteins

Golgi Apparatus

modify, ship out, package proteins for outside cell use with vesicles

What would happen if a protein was in the wrong location?

Errors, as location = function

What’s the endomembrane region made up of?

Nucleus → ER → Golgi Apparatus (protein making)

Lysosomes

filled w digestive enzymes to break down stuff

Peroxisomes

metabolizes toxic waste

Vacuole

present in plants and helps store things/maintain rigidity

Mitochondria

has outer membrane and cristae (folds) to maximize ATP metabolism

Chloroplast

makes energy for plants

What’s so special about the mitochondria and Chloroplasts? The answer: Endosymbiotic Theory

A large Eukaryotic cell enveloped a prokaryotic cell long ago and led to mitochondria and chloroplasts being very different than their other organelles.

Evidence:
- 70s ribosomes like bacteria

• binary fission

• circular DNA like bacteria