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Micro Chapter 5

History of Eukaryotes

1. 1st about 2 billion years ago
2. eukaryote evolving from prokaryote organisms thru intracellular symbiosis
a. euk. organelles originated from prokar. cells trapped inside them
b. 1st euk. probably single-celled & independent
c. eventually formed colonies
d. cells w/in colonies became specialized, working together & then specialized
e. evolved into multicellular organisms
3. Euk. have many levels of cellular complexity
a. compartmentalization = dividing into compartments & they specialize. ex. tissue has specific function

symbiosis

living together/association. one entered into another cell

Protozoa
what domain, kingdom & unicellular or mutli

Eukaroyte
KIngdom Protista
always unicellular

Fungi/Algae
what domain, kingdom & unicellular or mutli

Eukaryote
may be unicellular or multicellular

Helminths
what domain, kingdom & unicellular or mutli

Eukaryote
always multicellular (have unicellular egg or larval forms

Cilia & Flagella (Locomotor appendages)

1. Eukaryote flagella different from those of Prokaryote
a. 10X thicker/bigger
b. structurally more complex
c. covered by an extension of cell membrane
2. Single flagellum contains regularly spaced microtubules along its length
a. 9 pairs surrounding a single pair
b. 9+2 arrangement = is a universal pattern of flagella & cilia, 9 doublets surrounding 2 singlets

9+2 arrangement

is a universal pattern of flagella & cilia, 9 doublets surrounding 2 singlets

Cilia

used for movement or feeding

similar to flagellum w/some differences
1. shorter & more numerous than flagellum
2. can function as feeding and filtering structures

Only found in eukaryotes. protozoa & certain animal cells

Glycocalyx

1. glycocalyx (sugar-coat), a polysaccharide
2. Most euk. cells have this outermost boundary that comes into direct contact w/ the environment
3. usually composed of polysaccharides (many sugars)
4. appears as network of fibers, slime layer or capsule
5. functions=adhesion, protection, reception of signals (i.e. communication)
6. layer beneath varies among euk. fungi & algae have a thick, rigid cell wall. Protozoa & animal cells do not have a cell wall.

Eukaryotic Cell - Boundry Structures
Cell Wall

1. rigid
2. provide support & shape
3. different chemically from prok. cell walls
4. Fungi
a. thick inner layer of chitlin or cellulose
b. thin outer layer of mixed gylcans (sugar)
5. Algae
a. varied in chemical composition

Eukaryotic Cell - Boundry Structure
Cytoplasmic Membrane

1. Bilayer of phospholipids w/protein molecules embedded
2. also contain sterols, a type of lipid or fat
a. gives stability (too much and its a problem)
b. especially important in cells w/o a cell wall
3. selectively permeable barriers

sterols

a type of lipid or fat

Eukaryotic Cell - Internal Structures
Nucleus

Control center, all genetic information
1. separated from cytoplasm from nuclear membrane/envelope
a. 2 parallel membranes separated by narrow space (equals a total of 4 phospholipids
b. nuclear membrane perforated w/nuclear pores
2. filled w/nucleoplasm
3. contains the nucleolus
a. rRNA synthesis (which makes ribosomes, ribosomes make protein)
b. collection area for ribosomal subunits
4. Chromotin - comprises the chromosomes
a. long, linear DNA molecules
b. bound to histone proteins
c. visible during mitosis

cytoplasm vs. nucleoplasm

specialized enzymes dissolve w/in it

chromatin

comprises the chromosomes
chromatin like angel hair pasta
chromosomes like bowtie pasta
chromatin condenses into chromosomes for mitosis and wraps around histones (like a yo-yo)

Mitosis

Interphase = normal function, DNA = chromatin
Prophase
Metaphase=chromosomes line up
Anaphase= sister chromatid split toward centrioles
Telophase=
cytokinesis= division of cytoplasm, 2 daughter cells

Ribosomes

1. Protein synthesizers
2. Located = cytoplasm, cytoskeletan, RER, can be in groups
3. often found in chains of polyribosomes
4. composed of large & samll subunits of ribonucleicprotein
5. larger 80S variety, composed of 60S & 40S (how fast do they settle during centrifugation

S=Svelberg unit

Endoplasmic Reticulum (ER)

A passageway in the cell. continuation of nuclear membrane
1. microscopic series of tunnels
2. used in transport & storgage
3. Rough (RER)
a. originates from outer membrane of nuclear envelope
b. extends thru cytoplasm
c. spaces in RER=cisternae - transport material from nucleus to cytoplasm
d. "rough" b/c ribosomes attached to surface, typically making protein
e. protein synthesized on ribosomes shunted into cavity of RER & held for later packaging and transport

organelles

all membrane bound, 4 layers of phospholipids

Smooth Endoplasmic reticulum (SER)

1. closed tubular network
2. no ribosomes
3. Functions
a. nutrient processing
b. synthesis & storage of non-protein. macromolecule such as lipids
***c. membranes phospholipids being made
d. lipid synthesis

Gogli Apparatus 1/2

A packaging machine (post office of the cell)
One side faces nucleus (specifically ER) & one faces cell membrane
1. where proteins are modified & sent ot their final destinations (full of enzymes)
2. A stack of cisternae
3. do not form a continuous network

Golgi Apparatus 2/2

Closely associated w/ER both in location & function
1. ER buds off transitional vesicles (packets of protein) where it meets Golgi app.
2. Golgi app picks up transitional vesicles
3. protein often modified by addition of polysaccharides & lipids
4. Then golgi app pinches off condensing vesicles
a. sent to lysosomes (contain hydrolytic[water loosening] enzymes. enzymes are catalitic enzymes=protein
b. or transported out of cell

Lysosome

"break body" Clean up
1. contains variety of enzymes
2. involved in intracellular digestion of food & protection against invading microorganisms
3. participate in digestion & removal of cell debris in damaged tissue

phagocytosis

cell eating.
type of endocytosis in which the cell membrane actively engulfs large particles or cell into vesicles

pinocytosis

cell drinking

endocytosis

"in cell"

process where solid and liquid materials are taken into the cell thru membrane invagination & engulfment into a vesicle

phagolyosome

body forned in a phagocyte, consisting of a union btw a vesicle containing the ingested particle (the phagosome) and a vacuole of hydrolytic enzymes (the lysosome)

Mitochondria

Energy generators
1. cellular activities require constant supply of energy (ATP)
2. bulk of the energy generated by mitochondria
3. smooth, continuous outer membrane
4. inner folded membrane (fold are cristae)
a. critae hold enzymes & electron carriers of aerobic respiration
b. spaces around cristae fille w/matrix. matrix contents are ribosomes, dna & the pool of enzymes, other compounds involved in the metabolic cycle (dissolved enzymes, enzymes for Krebs cycle)
5. divide independently of cell
6. contain circular strands of dna (resemble bacteria-circular dna) dna comes from mother
7. contain prokaryotic-sized 70S ribosomes

Chloroplasts

Photosynthesis Machines
1. organelles found in algae & plant cells
2. convert energy of sunlight into chemical energy thru photosynthesis
3. 2 membranes
a. smooth outer membrane
b. inner membran folded into thylakoids
c. thylakoids stacked upon one another into grana (multiple)
d. contain chlorophyll & sometimes other pigment
4. stroma surrounds the thylakoids
70S ribosomes
dna-circular

thylakoids

small, disclike sacs

grana

thylakoids stacked upon one another
grana=multiple
granum=singular

stroma

surrounds the thylakoids. fluid inside has enzymes for photosynthesis

Endosymbiotic Theory

eukaryotic cells arose when a much larger prok. cell engulfed smaller bacterial cells that becan to live & reproduce inside the prok. cell rather than being destroyed. As smaller cells took up permanent residence they came to perform specialized function for the larger cell, such as food synthesis & O2 utilization, that enhanced the cell's versatility and survival. Over time, the engulfed bacteria gave up their ability to live independently and transferred some of their genes to the host cell.

invagination of membrane surrounding. engulfed smaller organism.

Endosymbiotic Theory - Evidence

A. mitochondria & chloroplasts
1. circular dna
2. same size ribosomal subunits=70S
3. reproduce independently
4. Overall size = prokaryote
b. flagellum = 10X greater
spriochete ancestor

Chloroplasts come in last. easier to lose one thing (chloroplast) then to gain everything. Mitochondria in everything

Compare & contrast Mitochondria & Chloroplast

A. mitochondria & chloroplasts
1. circular dna
2. same size ribosomal subunits=70S
3. reproduce independently
4. Overall size = prokaryote

Mitochondria = energy/ATP
Chloroplast = Photosynthesis

Cytoskeletan

1. A support network
2. flexible framework of molecules crisscrossing cytoplasm
3. Functions= anchoring organelles; moving organelles, RNA & vesicles; permitting shape changes & movement in some cells; support
4. Two types: originate from nucleus
a. microfilaments
b. microtubules- bigger

Microfilaments

1. thin protein strands
2. attach to cell membrane
3. some responsible for movements of cytoplasm
4. some active in amoeboid motion-pushes membrane out
5. like subway or train tracks

Why would items move in the cytoplasm?

Microfilament responsible for movement

eukaryote cells compartmentalize
more products created in one area to move to another

Microtubules

1. bigger than microfilaments
2. long, hollow tubes
3. maintain shape of eukaryote cells w/o walls
4. transport substances-bigger
5. responsible for movement of cilia & flagella in eukaryote only (9+2 arrangements)

ex. chameleon changing colors

eukaryotic cells function or structure

I. Genetics:
Characteristic: nucleic acid, chromosomes, true nucleus & nuclear envelope = most have it
II. Reproduction
Characteristic: mitosis, binary fission, production of sex cells = most have it
III. Biosynthesis
Characteristic: independent, golgi app, ER, ribosomes=most have it
IV. Respiration
Characteristic: enzymes, mitochondria=most have it
V. Motility/Locomotor structures
Characteristic: Flagella & cilia=some have it, some do not
VI. Shape/Protection
Characteristic: membrane= most have it
cell wall, capsule= some have it, some do not
VII. Complexity of function=most have it
VIII. Size = 2-100um

Kingdom of Fungi

1. great variety & complexity
2. approx. 100,000 species
3. divided into 2 groups
a. macroscopic fungi (mushrooms & puffballs)
b. microscopic
i. yeasts = round oval shape
unique mode of asexual resproduction called budding
ii. Hyphae (hairlike) = long, threadlike cell
iii. some are dimorphic = take either form of yeast or hyphae
4. majority are unicellular or colonia

dimorphic

"two-form"

take either form of yeast or hyphae

colonial

individual cells working together

Fungal nutrition

1. hetrotophic = acquire nutrition from other/different sources
2. acquire most nutrients from substrate = specific molecule upon which an enzyme acts
3. most fungi are saprobes = microbe that decomposes organic remains from dead organisms
4. can absorb a wide variety of substrates
5. large medical (penicillin) & agricultural (added to soil to help roots take up nutrients) importance

substrates

specific molecule upon which an enzyme acts

saprobes

microbe that decomposes organic remains from dead organisms

Fungal nutrition
general method of obtaining nutrition

land and penetrate the substrate & secrete exo-enzymes. breakdown large molecules into smaller molecules, then absorb.

Organization of microscopic Fungi

1. most grow in loose associations or colonies
2. yeasts; soft, uniform textures & appearance (almost like bacteria)
3. Filamentous fungal colonies- cottony, hairy, or velvety textures
4. Mycelium- the woven, intertwining mass of hyphae that makes up the body or colony of a mold
5. Unique organizational features of hyphae
a. Septa-cross walls (ex. nose, heart)
b. Nonseptate hyphae- one long, continuous cell
6. Functions of hyphae
a. Vegetative hyphae (mycelia)- visible mass of growth on the substrate surface; penetrates the substrate to digest and absorb nutrients. Going thru & doing their normal function.
b. Reproductive (fertile) hyphae- from vegetative hyphae; responsible for the production of (38) __spores_______

septa

cross walls

Mycelium

the woven, intertwining mass of hyphae that makes up the body or colony of a mold

Unique organizational features of hypae in fungi

a. Septa-cross walls (ex. nose, heart)
b. Nonseptate hyphae- one long, continuous cell

Functions of hyphae in fungi

a. Vegetative hyphae (mycelia)- visible mass of growth on the substrate surface; penetrates the substrate to digest and absorb nutrients. Going thru & doing their normal function.
b. Reproductive (fertile) hyphae- from vegetative hyphae; responsible for the production of (38) __spores_______

Roles of Fungi in Nature and Industry

1. Nearly all fungi are free-living and don't need a host
2. Human infection by pathogenic fungi usually occurs through accidental contact (ex. athletes foot-ring worm)
3. When/why do women get yeast infections? after antibiotics. kill the good & bad bacteria, but not fungi. take yogurt to prevent.
4. Humans are generally resistant to fungal infection, except for two main types
a. Primary pathogens = you will get sick
b. Opportunistic pathogens = ie. yeast
5. Mycoses vary in the way the agent enters the body and the degree of tissue involvement
Myco = (40) ___fungus_____________

major fungal infections of humans (1)

name of infection = candidiasis or yeast infection
name of causative fungus = candida albicans
degree of tissue involvement & area infected = mucous membranes, skin, nails (ex. yeast, thrush, throat infections)

Fungi not only involved in infections but (3=APA)

-Allergies (mold)
-Poisoning (exoenzymes)
-Agricultural damage

benefits of fungi (4)

1. Decomposing organic matter and returning essential minerals to the soil (recycling)
2. Mycorrhizae (fungi root) form a (41) _symbiotic__ relationship with plant roots to absorb water and nutrients. endo or exomycorrhizae
3. Production of
-Antibiotics (penicillin)
-Alcohol
-Organic acids
-Vitamins
4. Food flavorings

the protists

eukaryote
1. Traditionally contains the algae and protozoa
2. Two major taxonomic categories
I. Subkingdom Algae
II. Subkingdom Protozoa

Biology of Protozoa

animal like, in motion
1. About 65,000 species
2. Most are (42) harmless__, free-living inhabitants of water and soil
3. Few are parasites
4. Most are single cells
5. Size between 3 to 300 µm
6. Some ciliates and flagellates have organelles working like a primitive nervous system

Protozoan pathogens

1.Protozoan= Amoeboid
Disease= amoebiasis: Entamoeba histolytica (breakup tissue)
Source=human/water & food (ex. montezuma's revenge
2. Protozoan=flagellated protozoa/hemoflagellates
Disease=Trypanosomiasis:Trypanosoma brucei (T. cruzi)
Source= zoonotic/vector-borne (insects)
3. Protozoan= Apicomplexan Protozoa
Disease=Malaria: Plasmodium vivax
Source= zoonotic/vector-borne (ex. mosquitos)
4.Protozoan= Apicomplexan Protozoa
Disease=toxoplasmosis:Toxoplasma gondii
Source= zoonotic/vector-borne (ex. animal feces)

Algae: Photosynthesis protists

autotroph
1. Vary in length from a few micrometers to 100 meters
2. Unicellular, colonial, and filamentous forms
3. Larger forms can possess tissues and simple organs
4. Exhibit all eukaryotic organelles (more complex)
5. Chloroplasts contain chlorophyll as well as other pigments
6. One of the main components of plankton (define plankton [43]) microscopic organism that make up the base of the food web
7. Rarely infectious
8. Primary medical threat: shellfish exposed to red tide (what is red tide? 44) food poisoning which you accum toxins
(ex. Dinoflagellates - bloom, keep replicating. shell fish eat a lot of them & it accumulates & harmful for humans to eat.

Pathogenic flagellates: Trypanosomes

1. Genus Trypanosoma
2. T. brucei causes sleeping sickness (insects)
3. T. cruzi causes Chagas disease
a. Multiply in the muscle and white blood cells
b. Can lead to inflammation, fever, heart & brain

all hard to kill

Infective Amoebas

Entamoeba

1. Amoebiasis caused by Entamoeba histolytica
2. Fourth most common protozoan infection in the world
3. Aka amoebic dysentery
4. AKA - Montezuma's revenge

General worm morphology

1. Most developed organs are those of the (45) __reproductive_____ tract
2. Some degree of reduction in digestive, excretory, nervous, and muscular systems (ex. vingear eels-they had movement)
3. Most have thick cuticles for protection and mouth glands for breaking down the host's tissue
4. why would they need protection? (46) So their host can't penetrate & kill them. Human-your immune system is trying to get rid of them

The parasitic Helminths

1. Tapeworms, flukes, and roundworms
2. Adults large enough to be seen with the naked eye
3. From 1 mm to 25 m in length
4. Microscope is necessary to identify eggs and larvae
5. Two major groups: Flatworms and Roundworms
6. Worms and allergies???? Possible link between decrease number of worm infections led to an increase in allergies

A helminth cycle: The pin worm

1. Person swallows microscopic eggs
a. Picked up from another infected person by direct contact (rectum-come out at night to lay eggs)
b.Or by touching articles an infected person has touched
2. Eggs hatch in the intestine
3. Release larvae that mature in to adult worms (about 1 month)
4. Male and female worms mate
5. Female migrates out of the (47) anus_ to deposit eggs
6. Causes intense itchiness
7. Relieved by scratching
8. Scratching contaminates the fingers which transfer the eggs
9. Eggs spread to others or the original host reinfects him or herself

Flatworms

1. Phylum Platyhelminthes
2. Thin
3. Often segmented
4. Lack of or highly reduced (48)_digestive__ tract. Main focus is reproduction
5. Subdivisions
a. Cestodes (tapeworms)
b. Trematodes (flukes) - infectious locations? (49) blood & liver (block liver & blood)

Roundworms

1. Phylum Nematodes
2. Elongated
3. Cylindrical
4. Unsegmented
5. Muscular systems

cristernae

spaces in the ER & Gogli

Cristae

folds in mitochondria

thylakoids

in chloroplast, inner membrane folds

Intestinal Nematodes 1/2
infective in egg

Ascaris Lumbricoides
Common name = Ascariasis
Life cycle requirement = humans
spread to humans by = Fecal pollution of soil w. eggs

Intestinal Nematodes 2/2
infective in egg

Enterobius vermicularis
Common name = Pinworm
Life cycle requirement = Humans
spread to humans by = close contact (rectum)

Intestinal Nematodes (1)
infective in larval stage

Trichinella spiralis
common name = Trichina worm
life cycle requirement = pigs, wild mammals
spread to humans by = consumption of meat containg larvae (undercooked pork)

Flatworms (1/3)

Trematodes (fluke)
Schistosoma japonicum
common name= blood fluke
life cycle requirement = humans & snails
spread to humans by = ingestion of fresh water containing larval stage

Flatworms 2/3

Cestodes (tapes)
T. solium
common namepork tapeworm
life cycle requirement = humans, swine
spread to humans by =consumption of undercooked or raw pork

Flatworms (3/3)

Cestodes
Diphyllobothrium latum
common name = fish tape worm
life cycle requirement = humans, fish
spread to humans by = consumption of undercooked or raw fish

platyhelminthes

flatworms
cestodes=tapeworms
trematodes=fluke

nematodes

roundworms

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