Eukaryotic Cells and Microorganisms Flashcards
How long have ancient eukaryotic protists been around for?
2 million years
Lynn Margulis
provided sufficient evidence for the evolution of eukaryotic cells through the Endosymbiotic Theory
Endosymbiotic theory
- invagination of the plasma membrane surrounding DNA (protects DNA with 2 membrane system)
- obligate intracellular parasite enters into the larger cell
- the parasite and cell create a symbiotic relationship between the parasite and cell (becomes mitochondria and created ATP)
- cyanobacteria was absorbed by the cell and helped the cell convert sunlight into sugar for the cell
Pros and Cons: Endosymbiotic theory
pros: addresses evolution of mitochondria and presence of chloroplasts
cons: does not address the evolution of other organelles
Evidence of the endosymbiotic theory
- chloroplasts and mitochondria have circular DNA
- chloroplasts and mitochondria contain 70S ribosomes
- linear DNA in nucleus
- chloroplasts similar to cyanobacteria
- mitochondria is similar to rickettsia
- mitochondria: inner membrane more bacteria, outer membrane more eukaryotic
When did multicellular organisms start to evolve?
650 mya
Arrangement of microtubules in flagella
9+2 arrangement; 9 pairs surrounding 2 tubulins
Eukaryotic flagella movement
whipping movement
What is eukaryotic flagella made of?
microtubules
How much larger is eukaryotic flagella in comparison to prokaryotic flagella
10x larger
What eukaryotic groups have flagella?
some protazoa and algae, few animal cells
Cilia characteristics
structure used for movement which is made of microtubules, short and ore frequent on the body of the eukaryotic cell, move in a wave like movement
Where are eukaryotic cilia present?
some protazoa and in human bodies
Cell wall is made up of three groups
chitin, glycoprotein, mixed glycans
Biggest internal structure in eukaryotes
nucleus
Membrane which surrounds the nucleus
nuclear envelope
Nuclear envelope makeup
2 phospholipid bilayer
Nuclear pores
protein holes which allows for the regulated movement of molecules into and out of the nucleus
Nucleolus
site of ribosome synthesis in the nucleus
Chromatin
DNA wrapped in histones
Histones
type of protein
DNA is made up of…
chromosomes
- linear and 46 pieces
Diploid
2 copies of every chromosome/gene
Mitosis stages
- Prophase
- Metaphase
- Anaphase
- Telophase
Prophase
cells prepare to divide
Metaphase
chromosomes line up
Anaphase
chromosomes separate
Telophase
chromosomes un-condense and form 2 new nuclear membranes
Smooth ER
lipid synthesis
Rough ER
protein synthesis
Golgi apparatus
single membrane system which is the site of processing
How does the golgi apparatus transport molecules?
golgi packages materials into a membrane that buds off and is transported its destignated area
The Assembly Line
DNA copies information into mRNA > mRNA leaves through nuclear pores into cytoplasm > translated in the rough ER > golgi apparatus attaches and transports the molecule to its designated destination
Where do lysosomes come from?
golgi apparatus
Lysosome
site of breaking down materials
Vacuoles
storage site of some cells; materials/toxins are stored/dumped
Mitochondria
site of ATP synthesis using oxygen to convert sugar into ATP
Layer of mitochondria
inner and outer layer
Cristae
inner fold of mitochondria
Mitochondrial matrix
fluid filled space in the inner membrane of the mitochondria which contains 70s ribosomes/bacterial DNA
Chloroplasts 3 membrane system
outer membrane, inner membrane, thylakoid membrane
Thylakoid membrane
where photosynthesis occurs converting light energy to chemical energy (sugar); contains chlorophyll a
What is the waste product the thylakoid membrane produces when photosynthesis occurs?
oxygen
Stroma
fluid filled space of chloroplasts
Where is DNA/70S ribosomes found in chloroplasts?
stroma
What are eukaryotic ribosomes made of?
rRNA and ribosomal proteins
Where does protein synthesis occur?
cytoplasm and rough ER
Microfilaments
thinnest component of the filament which is made up of actin
Microfilament movement
oozing
What are microfilaments involved in?
cell movement and cell division
Microfilament cell division
moves the plasma membrane and pinches it to divide them into two cell
Microtubules
small tubes made of tubulin protein; can help move organelles
Microtubules cell division
grab onto chromosomes and pulls them apart
Cytoskeleton
microtubules, microfilaments, intermediate filaments
5 supergroups of eukarya
plants, SAR, excavates, ameobazoans, opisthokonts
Plants
include plants, green algae, and red algae
SAR
include brown algae, diatoms, apicomplexans (protazoa), dinoflagelletes, cilliates
Excavates
flagella protazoa, euglena
Ameobazoans
ameobas
Opisthokonts
animal, fungi
Macroscopic fungi
fungi which can be seen with the naked eye
Microscopic fungi
yeast and molds
Fungal shapes
yeast (ovoid/large in size) and hyphal shape
Yeast
shiny, unicellular
Hyphae
thread like structure found in mold
Mycelium
hyphae in large groups which form mold surface
Hyphal structures can be…
septate: nucleus is separated throughout the hyphae
non-septate: nuclei are not seperated by a wall
Fungi is dimorphic
can switch between hyphal and yeast shape
What causes fungi to change shapes?
based on temperature
Fungal nutrition
heterotrophic (eat other organisms)
Saprobe
eat dead organisms/mater
Substrate
surface where the microbe is grown
Fungal advantages
due to their strong digestive enzymes that transport food molecules into the cell, they are able to live in nutrient poor environments
Asexual fungal spores
sporangiospore, conidia
Sporangiospore
surrounded by sac
Conidia
not surrounded by sac and releases when ready; more common
Can all fungi produce sexual spores?
yes
Sexual Fungal Reproduction
zygospores, ascospores, basidiospores, chytrids
Zygospores
strong spiny walls (bread and fruit mold)
Ascospores
8 spores enclosed in a sac (cup fungi)
Basidiospores
club like structure which spores come off (toad stools)
Classification of fungi is based on…
appearance of reproductive spores
Chytrids
fungi which have caused the death of many amphibians
What must occur for a fungal infection to occur?
weakened immune system
Classification of algae is based on…
color
What shape in algae is unique between the species?
chloroplasts
Diatomaceous earth
silica cell walls of the diatoms formed on the earth
algae characteristics
form agar, make up portion of oxygen, cannot get people sick
Classification of SAR is based on…
motility
Protazoan nutrition
heterotrophs
Protazoa cytoplasm
2 cytoplasm: ectoplasm and endoplasm
Ectoplasm
cytoplasm underneath the cell membrane
Endoplasm
where nucleus and organelles are
SAR nuclei
can have two nuclei: macronucleus and micronucleus
Macronucleus
necessary genes for life
Micronucleus
contains advantageous genes
SAR
apicomplexa, ciliates, excavata, ameobazonas
Apicomplexa
parasite which lacks motility due to them being in the “perfect” environment
Ciliates
move by cilia; have no effect on human health
Excavata
move by flagella
Ameobazoans
move with ameboid movement using psuedopods
Parasitic Roundworm Phylums
Nematoda and Platyhelminthes
Phylum Nematoda
nematodes
Phylum Platyhelminthes
flukes and tapeworms
