Nothing Special   »   [go: up one dir, main page]

NCMC103 Prelims Reviewer

Download as pdf or txt
Download as pdf or txt
You are on page 1of 13

ATENEO DE NAGA UNIVERSITY

COLLEGE OF NURSING BATCH 2025


MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

COURSE OUTLINE: PRELIMS physiology, molecular biology, ecology, evolution


and clinical aspects of viruses
1. INTRODUCTION TO MICROBIOLOGY
2. HISTORY OF MICROBIOLOGY
3. CELL STRUCTURE AND FUNCTION PROCESS-CENTERED

REFERENCE BOOK MICROBIAL METABOLISM


● biochemistry: chemical reactions within the cells

MICROBIAL GENETICS
● functions of DNA and RNA
INTRODUCTION TO MICROBIOLOGY
ENVIRONMENTAL MICROBIOLOGY
MAIN THEMES OF MICROBIOLOGY ● relationship between microbes and among
● the scope of microbiology microbes, other organisms, and environment
● the impact of microbes on earth: small organisms
with a giant effects APPLIED MICROBIOLOGY
● human use of microorganisms
● infectious diseases and the human condition MEDICAL MICROBIOLOGY

SCOPES AND FIELDS OF MICROBIOLOGY SEROLOGY


A. Basic Research ● antibodies in blood serum, particularly as an
a. microbe-centered indication of infection
b. process-centered
B. applied microbiology IMMUNOLOGY
a. medical microbiology ● body;s defenses against disease
b. applied environmental microbiology
c. industrial microbiology EPIDEMIOLOGY
BASIC RESEARCH ● frequency, distribution, and spread of diseases

MICROBE-CENTERED ETIOLOGY
● cause of disease
BACTERIOLOGY
INFECTION CONTROL
● Bacteriology is the branch and specialty of biology
that studies the morphology, ecology, genetics and ● hygiene in health care settings and control of
biochemistry of bacteria as well as many other nosocomial infections
aspects related to them
CHEMOTHERAPHY
PROTOZOOLOGY ● development and use of drugs to treat infectious
● Protozoology is the study of protozoa, the diseases
"animal-like" (i.e., motile and heterotrophic) protists
APPLIED ENVIRONMENTAL MICROBIOLOGY
PHYCOLOGY
● Phycology is the science that studies all forms of BIOREMEDIATION
algae, from very tiny microorganisms that float ● use of microbes to remove pollutants
through the ocean to huge forests of seaweed.
PUBLIC HEALTH MICROBIOLOGY
PARASITOLOGY ● sewage treatment, water purification, and control of
● Parasitology is the scientific discipline concerned insects that spread diseases
with the study of the biology of parasites and
parasitic diseases AGRICULTURAL MICROBIOLOGY
● use of microbes to control insect pests
MYCOLOGY
● the study of fungi, a group that includes the FOOD AND BEVERAGE TECHONOLOGY
mushrooms and yeasts ● reduction and elimination of harmful microbes in
food and drink
VIROLOGY
● Virology is the scientific discipline concerned with PHARMACEUTICAL MICROBIOLOGY
the study of the biology of viruses and viral ● manufacture of vaccines and antibiotics
diseases, including the distribution, biochemistry,

1 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

RECOMBINANT DNA TECHNOLOGY ○ Molds – multicellular; grow as long


● alteration of microbial genes to synthesize useful filaments; reproduce by sexual and
products asexual spores
● ex: Bt Corn ● Yeasts – unicellular; reproduce asexually by
budding; some produce sexual spores
EFFECTS OF MICROORGANISMS
PROTOZOA
BENEFITS ● Single-celled eukaryotes
● bioremediation - decomposing organic waste ● Similar to animals in nutrient needs and cellular
● biotechnology - producing ethanol, acetone, structure
vinegar, cheeses, bread, etc. ● Live freely in water; some live in animal hosts
● producing insulin and many other drugs ● Asexual (most) and sexual reproduction
● some microorganisms like bacteria and fungi are ● Most are capable of locomotion by
important sources of antimicrobial agents ○ Pseudopods – cell extensions that flow in
direction of travel
HARMFUL EFFECTS ○ Cilia – numerous short protrusions that
● harmful microbes produce toxins to spoil our food propel organisms through environment
leading to food poisoning ○ Flagella – extensions of a cell that are
● harmful microbes can spoil our leather, clothing, fewer, longer, and more whip like than cilia
and etc.
● harmful microbes cause diseases in humans,
animals and plants. ALGAE
● Unicellular or multicellular
● Photosynthetic
● Simple reproductive structures
HISTORY OF MICROBIOLOGY ● Categorized on the basis of pigmentation and
composition of cell wall
EARLY YEARS IN MICROBIOLOGY
● First observation of microbial life OTHER ORGANISM
● Initial efforts to organize them into logical ● PARASITES AND VIRUSES
classification
● By the end of 19th century, these organisms were
called microorganisms
● Leewehhoek’s microorganisms now grouped into
six categories
○ Bateria
○ Archae
○ Fungi
○ Protozoa
○ Algae
○ Small multicellular animals

HOW ARE MICROBES CLASSIFIED?

● Carolus Linnaeus developed taxonomic system for


naming plants and animals and grouping similar
organism together

BACTERIA AND ARCHAE GOLDEN AGE OF MICROBIOLOGY


● Unicellular and lack nuclei (Prokaryotic)
● Found everywhere there is sufficient moisture; DOES MICROBIAL LIFE SPONTANEOUSLY
some isolated from extreme environments GENERATE?
● Reproduce asexually ● Some philosophers and scientists of the past
● Bacterial cell walls contain peptidoglycan; some thought living things arose from three processes
lack cell walls ○ asexual reproduction
● Archael cell walls composed of polymers other than ○ sexual reproduction
peptidoglycan ○ nonliving matter
● Aristotle proposed spontaneous generation
FUNGI ○ living things can arise from nonliving
● Eukaryotic (have membrane-bound nucleus) matter
● Obtain food from other organisms ● Redi’s experiment
● Possess cell walls ○ When decaying meat was kept isolated
● Include from flies, maggots never developed

2 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

○ Meat exposed to flies was soon infested ○ Techniques for estimating


○ As a result, scientists began to doubt ○ CFU/ml
Aristotle's theory ○ Use of steam to sterilize media
● Needham's experiments ○ Use of Petri dishes
○ Scientists did not believe animals could ○ Techniques to transfer bacteria
arise spontaneously, but believed ○ Bacteria as distinct species
microbes could ● Koch's postulates
○ Needham's experiments with beef gravy ○ Suspected causative agent must be found
and infusions of plant material reinforced in every case of the disease and be absent
this idea from healthy hosts
● Spallanzani's experiments ○ Agent must be isolated and grown outside
○ Concluded that Needham failed to heat the host
vials sufficiently to kill all microbes or had ○ When agent is introduced into a healthy,
not sealed vials tightly enough susceptible host, the host must get the
○ Concluded that Microorganisms exist in air disease
and can contaminate experiments ○ Same agent must be found in the diseased
○ Concluded that Spontaneous generation of experimental host
microorganisms does not occur
○ Critics said sealed vials did not allow
enough air for organisms to survive and HOW CAN WE PREVENT INFECTION AND
that prolonged heating destroyed the "life DISEASES?
force ● Semmelweis and handwashing
● Pasteur's experiments ● Lister's antiseptic technique
○ When the "swan-necked" flasks remained ● Nightingale and nursing
upright, no microbial growth appeared ● Snow – infection control and epidemiology
○ When the flask was tilted, dust from the ● Jenner's vaccine – field of immunology
bend in the neck seeped back into the ● Ehrlich's "magic bullets" – field of chemotherapy
flask and made the infusion cloudy with
microbes within a day
MODERN AGE OF MICROBIOLOGY
WHAT CAUSE FERMENTATION?
● Spoiled wine threatened livelihood of vintners WHAT ARE THE BASIC CHEMICAL REACTIONS OF
● Some believed air caused fermentation; others
LIFE
insisted living organisms caused fermentation
● Vintners funded research of methods to promote ● Biochemistry
production of alcohol and prevent spoilage during ○ Began with Pasteur's work on fermentation
fermentation and Buchner's discovery of enzymes in
● This debate also linked to debate over spontaneous yeast extract
generation ○ Kluyver and van Niel – microbes used as
● Pasteur's experiments model systems for biochemical reactions
○ Led to the development of pasteurization ○ Practical applications
○ Process of heating liquids just enough to ■ Design of herbicides and
kill most bacteria pesticides
○ Began the field of industrial microbiology ■ Diagnosis of illnesses and
○ Intentional use of microbes for monitoring of patients' responses
manufacturing products to treatment
● Buchner's experiments ■ Treatment of metabolic diseases
○ Demonstrated fermentation does not ■ Drug design
require living cells
○ Showed enzymes promote chemical HOW DO GENES WORK?
reactions ● Microbial genetics
○ Began the field of biochemistry ○ Avery, MacLeod, and McCarty determined
genes are contained in molecules of DNA
WHAT CAUSES DISEASE? ○ Beadle and Tatum established that a
● Pasteur developed germ theory of disease gene's activity is related to protein function
● Robert Koch studied causative agents of disease ○ Translation of genetic information into
● (etiology) protein explained
○ Anthrax ○ Rates and mechanisms of genetic
○ Examined colonies of microorganisms mutation investigated
● Koch's experiments ○ Control of genetic expression by cells
○ Simple staining techniques described
○ First photomicrograph of bacteria ● Molecular biology
○ First photomicrograph of bacteria in ○ Explanation of cell function at the
diseased tissue molecular level

3 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

○ Pauling proposed that gene sequences


could number cell
■ Provide understanding of
evolutionary relationships and responsiveness: occurs occurs occurs in some
processes ability to react to in all in all viruses as a
■ Establish taxonomic categories to environmental reaction to host
reflect these relationships stimuli cells
■ Identify existence of microbes
that have never been cultured metabolisn: occurs occurs uses host’s
○ Woese determined cells belong to controlled in all in all cells
bacteria, archaea, or eukaryotes chemical metabolism
● Recombinant DNA technology reactioons of
○ Genes in microbes, plants, and animals organisms
manipulated for practical applications
○ Production of human blood-clotting factor cellular structure: present present lacks
by E. coli to aid hemophiliacs membrane-boun in all cytoplasmic
● Gene therapy d structure membrane or
○ Inserting a missing gene or repairing a capable of all the cellular
defective one in humans by inserting above functions structure
desired gene into host cells

WHAT ROLE DO MICROORGANISMS PLAY IN THE PROKARYOTES


ENVIRONMENT ● do not have membrane surrounding their DNA; lack
● Bioremediation uses living bacteria, fungi, and a nucleus
algae to detoxify polluted environments ● lack various internal structures bound with
● Recycling of chemicals such as carbon, nitrogen, phospholipid membrane
and sulfur ● small ~1.0μm in diameter
● have a simple structure
HOW DO WE DEFEND AGAINST DISEASE? ● composed of bacteria and archaea
● Serology
○ The study of blood serum
○ Von Behring and Kitasato – existence in
the blood of chemicals and cells that fight
infection
● Immunology
○ The study of the body's defenses against
specific pathogens
● Chemotherapy
○ Fleming discovered penicillin
○ Domagk discovered sulfa drugs

WHAT WILL THE FUTURE HOLD?


● microbiology is built on asking and answering
questions
● the more questions we answer, the more question
we have EUKARYOTES
● have membrane surrounding their DNA; have a
nucleus
CELL STRUCTURE AND FUNCTION ●

have internal membrane-bound organelles
are larger, 10-100 μm in diameter
● have more complex structure
PROCESSES OF LIFE ● composed of algae, protozoa, fungi animals and
plants
processes of life prokery eukary viruses
otes otes

growth: increase occur in occurs doe not occue


in size all in all

reproduction: occurs occurs occurs only


increase in in all in all inside a host

4 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

EXTERNAL STRUCTURES OF PROKARYOTIC


CELLS

GLOCOCALYCES
● gelatinous, sticky substance surrounding the
outside of the cell
● composed of polysaccharides, polypeptides or both
TWO TYPES:
A. Capsule
○ composed of organized repeating units of
organic materials
○ firmly attached to cell surface
○ protect cells from drying out
○ may prevent bacteria from being
recognized and destroyed by host
SUMMARY: B. Slime layer
○ loosely attached to cell surface
○ water soluble
○ protects cells from drying out
CELL CELL WALL CELL ○ sticky layer that allows prokaryotes to
TYPE MEMBRANE attach to surfaces
ARCHAE prokaryotic polysaccharid the lipid
es and membrain is
proteins, either linked,
pseudo with the
murein branching of
aliphatic acids
R-O-R

BACTERIA prokaryotic made up of have lipid


peptidoglycan membrane of
with muramic ester bonds
acid with fatty acids
RCOOR

FUNGI eukaryotic chitin lipid bilayer


with sterol
(ergosterol)

ALGAE eukaryotic cellulose lipid bilayer, FLAGELLA


with sterols ● acts primarily as an organelle of locomotion
(phytosterols) ● types
○ monotrichous - single polar flagellum
PROTOZOA eukaryotic none lipid bilayer ○ amphitrichous - single flagellum on both
with sterols sides
(ergosterol) ○ lophotrichous- tufts of flagella at one or
both sides
ANIMALIA eukaryotic none lipid bilayer ○ Peritrichous- numerous flagella all over the
with sterols bacterial body
(cholesterol)

5 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

PROKARYOTIC CELL WALLS


● provide structure and shape and protect cell from
osmotic forces
● assist some cells in attaching to other cells or in
eluding antimicrobial drugs
● not present in animal cells, so can target cell wall of
bacteria with antibiotics
● bacteria and archaea have different cell wall
chemistry
a) peritrichous
b) monotrichous BACTERIAL CELL WALLS
c) lophotrichous ● most have cell wall composed of peptidoglycan
● peptidoglycan is composed of sugars, NAG, and
NAM
FIMBRIAE ● Chains of NAG and NAM attached to other chains
● rod-like proteinacrous extensions by tetrapeptide crossbridges
● sticky, bristlelike projections ○ bridges may be covalently bonded to one
● used by bacteria to adhere to one another, to host, another
and to substances in environment ○ bridges may be held together by short
● shorter than flagella connecting chains of amino acids
● may be hundreds per cell ● scientists describe two basic types of bacterial cell
● serve an important function in biofilms walls: Gram positive and Gram negative

GRAM POSTIVE CELL WALL


● relatively thick layer of peptidoglycan
PILI ● contain unique poly alcohols called teichoic acids
● tubules composed of pilin ○ some covalently linked to lipids, forming
● also known as conjugation pili lipoteichoic acids taht anchor
● longer than fimbriae but shorter than flagella peptidoglycan to cell membrane
● bacteria typically only have one or two per cell ● retain to crystal violet dye in Gram staining
● mediate the transfer of DNA from one cell to procedure; so appear purple
another (conjugation) ● up to 60% myolic acid in acid-fast bacteria helps
cells survive desiccation

6 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

TYPE 2:
● additional layers of material are present outside the
S-later.
● In Methanosprillum, there is aprotein sheath
GRAM NEGATIVE CELL WALLS external to S-layer
● have only a thin layer of peptidoglycan
● bilayer membrane outside the peptidoglycan
contains phospholipids,proteins, and
lipopolysaccharide (LPS)
● may be independent to the treatment of disease
● appear pink following gram staining procedure

TYPE 3:
● In methanosarcina, S-layer is covered by a
chondroitin like material called as
mathanochondroitin

ARCHAEAL CELL WALLS


● do not have peptidoglycan TYPE 4:
● contain variety of specialized polysaccharides and ● In some Archae like Methanothermus and
proteins Methanopyrus, S-layer is the outermost layer and is
● gram positive arcahea stain purple separated from the plasma membrane by a
● gram negative archae stain pink Peptidoglycan like molecule called psuedomurient
● Pseudomurien differ from Peptidoglycan in having
TYPE 1 N-acetyltalosaminurionic acid instead of N-acetyl
● the most common type of archaeal cell wall is an S muramic acid, L-amino acids instead of D-amino
layer composed of either protein or glycoprotein acids that cross links and beta ( 1→3) glycosidic
● 20-40nm thich linkage instead of bet (1→4) glycosidic linkage
● S-laye cell walls are present in some methanogens
like Methanococcus, Halophiles like Halobacterium
and extreme thermophiles like Sulpholobus,
Pyrodictium etc.

7 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

TYPE 5:
● in this type, S layer is absent. Instead archaeal cell
wall is single thick homogenous layer resembling
Gram positive bacteria.
● These archeae often stain gram positive
● this type is present in Methanobacterium
Halococcus etc.

PROKARYOTIC CYTOPLASMIC MEMBRANES


● Structure
○ Referred to as phospholipid bilayer;
composed of lipids and associated
proteins
○ Approximately half composed of proteins
that act as recognition proteins, enzymes,
receptors, carriers, or channels
■ Integral proteins
■ Peripheral proteins
■ Glycoproteins
○ Fluid mosaic model describes current
understanding of membrane structure
● Function
○ Energy storage
○ Harvest light energy in photosynthetic
prokaryotes
○ Selectively permeable
○ Naturally impermeable to most substances
○ Proteins allow substances to cross
membrane
■ Occurs by passive or active
processes
○ Maintain concentration and electrical
gradient
■ Chemicals concentrated on one NONMEMBRANOUS ORGANELLES
side of the membrane or the other ● Ribosomes – sites of protein synthesis
■ Voltage exists across the ● Cytoskeleton – plays a role in forming the cell’s
membrane basic shape

CYTOPLASM OF PROKARYOTES
EXTERNAL STRUCTURES OF EUKARYOTIC
CYTOSOL CELLS
● liquid portion of cytoplasm

GLYCOCALYCES
INCLUSIONS ● Never as organized as prokaryotic capsules
● may include reserve deposits of chemicals ● Help anchor animal cells to each other
● Strengthen cell surface
● Provide protection against dehydration
ENDOSPORES ● Function in cell-to-cell recognition and
● unique structures produced by some bacteria that communication
area defensive strategy against unfavorable ●
conditions

8 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

EUKARYOTIC CELL WALLS AND CYTOPLASMIC CYTOPLASM OF EUKARYOTES


MEMBRANES
● Fungi, algae, plants, and some protozoa have cell FLAGELLA
walls but no glycocalyx ● Structure and arrangement
● Composed of various polysaccharides ○ Shaft composed of tubulin arranged to
○ Cellulose found in plant cell walls form microtubules
○ Fungal cell walls composed of cellulose, ○ “9 + 2” arrangement of microtubules in all
chitin, and/or glucomannan flagellated eukaryotes
○ Algal cell walls composed of cellulose, ○ Filaments anchored to cell by basal body;
proteins, agar, carrageenan, silicates, no hook
algin, calcium carbonate, or a combination ○ Basal body has “9 + 0” arrangement of
of these microtubules
○ May be single or multiple; generally found
at one pole of cell
● Function
○ Do not rotate, but undulate rhythmically

● All eukaryotic cells have cytoplasmic membrane


● Are a fluid mosaic of phospholipids and proteins
● Contain steroid lipids to help maintain fluidity
● Contain regions of lipids and proteins called
membrane rafts
● Control movement into and out of cell CILIA
○ Use diffusion, facilitated diffusion, osmosis,
and active transport ● Shorter and more numerous than flagella
○ Perform endocytosis; phagocytosis if solid ● Composed of tubulin in “9 + 2” and “9 + 0”
substance and arrangements
○ pinocytosis if liquid substance ● Coordinated beating propels cells through their
○ Exocytosis enables substances to be environment
exported from cell ● Also used to move substances past the surface of
the cell

9 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

RIBOSOMES NUCLEUS
● Larger than prokaryotic ribosomes (80S versus ● Often largest organelle in cell
70S) ● Contains most of the cell’s DNA
● Composed of 60S and 40S subunits ● Semi-liquid portion called nucleoplasm
● One or more nucleoli present in nucleoplasm; RNA
synthesized in nucleoli
CYTOSKELETON ● Nucleoplasm contains chromatin – masses of DNA
● Extensive associated with histones
● Functions ● Surrounded by nuclear envelope – double
○ Anchors organelles membrane composed of two phospholipid bilayers
○ Cytoplasmic streaming and movement of ● nuclear envelope contains nuclear pores
organelles
○ Movement during endocytosis and
amoeboid action
○ Produces basic shape of the cell
● made up of tubulin microtibules, actin
microfilaments, and intermediate filaments

ENDOPLASMIC RETICULUM
● Netlike arrangement of flattened, hollow tubules
continuous with nuclear envelope
● Functions as transport system
● Two forms
○ Smooth endoplasmic reticulum (SER) –
plays role in lipid synthesis
○ Rough endoplasmic reticulum (RER) –
ribosomes attached to its outer surface;
CENTRIOLES AND CENTROSOME transport proteins produced by ribosomes
● Centrioles and centrosome
○ Centrioles play a role in mitosis,
cytokinesis, and in formation of flagella
and cilia
○ Centrioles composed of “9 + 0”
arrangement of microtubules
○ Centrosome is region of cytoplasm where
centrioles are found

GOLGI BODY
● Receives, processes, and packages large
molecules for export from cell
● Packages molecules in secretory vesicles that fuse
with cytoplasmic membrane
● Composed of flattened hollow sacs surrounded by
phospholipid bilayer
● Not in all eukaryotic cells

10 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

MITOCHONDRIA
● Have two membranes composed of phospholipid
bilayer
● Produce most of cell’s ATP
● Interior matrix contains 70S ribosomes and circular
molecule of DNA

CHLOROPLASTS
● Light-harvesting structures found in photosynthetic
eukaryotes
● Have two phospholipid bilayer membranes and
DNA
● Have 70S ribosomes

LYSOSOMES, PEOXISOMES, VACUOLES, ENDOSYMBIOTIC THEORY


VESICLES ● Eukaryotes formed from union of small aerobic
● Store and transfer chemicals within cells prokaryotes with larger anaerobic prokaryotes
● May store nutrients in cell ● smaller prokaryotes became internal parasites
● Lysosomes contain catabolic enzymes ○ Parasites lost ability to exist independently;
● Peroxisomes contain enzymes that degrade retained portion of DNA, ribosomes, and
poisonous wastes cytoplasmic membranes
○ Larger cell became dependent on
parasites for aerobic ATP production
○ Aerobic prokaryotes evolved into
mitochondria
○ similar scenario for origin of chloroplasts
● not universally accepted

11 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

12 I ©Jaye Anne Bernales


ATENEO DE NAGA UNIVERSITY
COLLEGE OF NURSING BATCH 2025
MICROBIOLOGY AND PARASITOLOGY IN DISEASE CAUSATION

ADAPTED FROM:SYNCHRONOUS SESSIONS/ POWERPOINT

SPECIAL NOTES:
COLOR THEME (HEX)
LESSON TITLE: #3c1361
MAIN TOPIC: #52307c
SUB TOPIC 1: #8958a8
SUB TOPIC 2: #a17fb6
SUB SUB TOPIC 1: #ceb0e0

13 I ©Jaye Anne Bernales

You might also like