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-uni/multicell; what do they make?
-Groups of Algae:
-relation to current events?
Groups of Algae:
- - Photosynthetic autotrophs; often aquatic
- -either uni or multicellular
- -Have chloroplasts with chlorophyll: light absorbing pigments
- -Many have cell walls made of cellulose: polysaccharide
- -Produce O2 during photosynthesis
Green Algae (ex: Chlamydomonas-round, single-celled), brown algae (kelp), diatoms, dinoflagellates.
: biodiesel from oils can be made by algae; but takes more energy to do /:
--> classification of medically imp protozoa by movement method:
Single celled; lack cell walls; many are motile and have complex life cycles "animal like"
-Heterotrophs: use organic source of carbon
Importance: They are decomposers; help digestion in cattle but some are pathogenic.
classification of medically imp protozoa by movement method: Cillia, Pseudopods (amoebas), Flagella or no specific method of movement
Asexual Reproduction of Protozoa
--> two types?
Fission: Mitosis + Cytokinesis: 1 cell divides into two so that offspring are completely identical to parent
Schizogony: One cell divides into many cells-multiple divisions (identical)
Sexual Reproduction of Protozoa:
what organisms do this?
Conjugation: paramecium do this: offspring are different from parents.
--> development of male and female gametocytes (done by Plasmodium species)
--> Occurs in definite host: sexually reproducing stage of parasite.
Trophozoite vs. Cyst forms: (Protozoa)
- Trophozoite: Active Feeding form, may not survive long outside of Host
- --> would most likely cause a waterborne disease that could be transmitted by drinking water since it is active.
- Cyst: Inactive parasite form; Resistant to destruction/chlorine
- --> permits organism to survive during unsuitable temp, lack of oxygen, food or moisture. Enables parasitic protozoa to survive outside host during excretion to a new host.
How are Parasites detected (4 ways)
- 1. Ova & Parasite detection by microscopy of stool sample (O&P exam)
- 2. PCR:aka "Polymerase Chain Reaction" DNA amplification for analysis
- 3. Blood smear under a microscopy.
- 4. Serological tests (type of differential testing) to detect antibodies in blood; because antibodies indicate exposure to parasites.
Flagellates Example 1: Trichomoniasis
Signs & symptoms
Example: Trichomonas vaginalis
(-Causes disease of the reproductive system (STD) called "trichomoniasis")
- Microbe Info: One-celled pathogenic protozoan
-Trophozoite is infectious: travels from host to host; men can be affected but unknown w/ 8 million infections yearly in N America
- Signs & symptoms:
- Men: irritation inside penis, mild discharge, slight burning during urination.
- Women: Painful uritnation, vaginal itching/irritation, greenish yellow discharge, intercourse discharge
: Microscopy/wet mount; cervical smears
: Oral antibiotics
: Condom Use
Flagellates Example 2: Giardiasis
Signs & symptoms ... add more
is caused by the flagellate: Giardia lamblia
-Intestinal parasite (small int)
: Greasy stool, gas, diarrhea, loss of appetite, blood in utrine, loose/watery stool, bloating/burping/excessive gass. Can appear 1-2 weeks AFTER infection and maybe wane cyclically.
: contaminated water/food, recreational, drinking water... Campers drinking untreated water at risk; diaper changers(stool).
- Cysts: responsible for disease spread, must remove cysts by filtering or boiling water.
- --> Dogs/cats can carry the parasite (distribute)
- --> chlorine doesn't kill cysts.
: OP exam, fluorescence microscopy
Treatment is available
: Filter/Boil water, good sanitation.
Apicomplexa: Example 1- Toxoplasmosis (ch 23)
- disease of blood and lymphatic vessels
- Symptoms: flu-like symptoms, muscle aches
- Normal people: body aches, swollen lymph nodes, headache, fever, fatigue and sorethroat
- Immunocompromised: Headache, confusion, poor coordination, seizures, lung problems resembling TB or Pneumona
- Transmission: Rodents= "Intermediate Host" & Cats="Definite host"; Human ingestion of oocysts while in contact with cat feces/contact with soil or contaminated meat. Can hid in eyes, brains, muscles...
- --> affects brain and eyes of immunocompromised people; causes stillbirth and vision problems in infected pregnant mom.
: Serological testing
only for active form
: wear gloves when dealing with cat litter, cook meat well.
Apicomplexa Example 2: Cryptosporidiosis
Caused by "Cryptosporidium hominis"
asymptomatic, cause acute diarrhea that can last weeks, or watery diarrhea w/ mucus. Also can be stomach pain, low fever, nausea, dehydration
- -Transmission: By oocysts; VERY contagious person to person. Contaminated water, food, soil or anything w/ infected human/animal feces. Pools, Tap water, certain water parks are source of outbreaks.
- --> serious disease for immunocompromised people
: Fluorescense Microscopy
: oral rehydration; salt solution
: Filter/boil water
: US cities
Malaria: Symptoms and Microbe info:
Life threatening disease in humans caused by Plasmodium parasite species (protozoans); Plasmodium falciparium is most severe.
: Fever, chills, headache , flu-like symptoms or periodically get sweats two weeks after bite ; timing of symptoms depends upon Plasmodium species.
- --> Flu: often confused with Malaria
- --> Life Threathening: Plasmodium can destroy RBC's and clog capillaries that lead to brain/other organs; US patients don't get prompt service due to misdiagnosis b/c it's uncommon here.
- --> vector still exists in US; possible for Malaria outbreaks
Microbe info: Plasmodium reproduce in human liver (dormant after initial illness FOR UP TO ONE YEAR; hence us travelers cannot donate blood for one year), enters RBC (eventually burst) and infects next mosquito that bites infected person.
Malaria: Transmission, Diagnosis, Treatment, Prevention, Location, and current Research/Concern
Practice Q: Why is it so difficult to eradicate malaria?
: Mosquitos are the vectors; transfers sporozoite form.
:Getting prompt medical attention if the person is a traveler; look Plasmodium in RBC of blood smear; "Rapid Diagnostic Test"
(RDT): detects antigen in 15 mins or less.
- 1.NO FDA approved vaccine yet;
- 2. Quinine (more resisted by Plamodium recently)
- 3. "Artemisinin combination therapy" (ACT): act of diff biochem pathways in parasite-recommended for countries w/ developed plasmodium resistance to previous drugs
- **shouldn't be used alone b/c there is a chance of developing resistance**
--USA got rid of Malaria by wide-spread use of DDT insecticide.
: Bed nets & clothing SOAKED in insecticide; antimalarial meds
(not 100 percent effective); DEET insect repllent and sleeping in w/screens/bednets/AC
: 109 countries. Including Africa, Asia & South America. (Not in US)
- Current Research/concerns: Malaria has been increasing due to Global warming since vectors enjoy warm temps
- --Malaria increases HIV viral load in blood o.0
- Practice Questions:
- 1. Why is it so difficult to eradicate malaria?
- b/c Plasmodium can hide in liver for one year D: there is no effective resistance, drug resistance issues and vector born illness.
Two types of Fungi:
1. yeast: divide how, example
2. Mold: Mycellium/septa? Dimorphism?
Yeast and Mold
- Yeast: typically unicellular, divide by fission (into equal halves) or budding (unequally; forms by protuberance on outer surface of parent cell)
- ex: Saccharomyces cerevisiae: Budding yeast in bread& beer
- Multicellular; have Hyphae: filaments made of chains of cells (NOT strepto).
- -Mycelium: entire visible mass of Hyphae.
- -Septa: separations b/w nuclei of hyphae, no cell wall
- Dimorphism: Two growth forms, strange because two different cell shapes can have same DNA
How do they reproduce?
- ⇾Chemoheterotrophs: inorganic carbon source
- ⇾ Cell walls: chitin (polysaccharide)
- ⇾ Most reproduce BOTH sexuallly and asexually: By formation of spores.
- ⇾Spores are reproductive.
Fungi Growth Conditions
pH, aerobic/anaerobic, environment enjoyed
- ⇾ pH 5 enviroment; sllightly acidic
- ⇾ Molds= aerobic
- ⇾ Yeasts: facultative anaerobes
- ⇾ sugary or salty environments prefered
- ⇾ very little moisture needed
- ⇾ breaks down dead organic material
Five reasons why Fungi are important?
- 1. Decomposers
- 2. Food production (yeast)
- 3. Food spoilage (economic losses)
- 4. Source of antibiotics (penicillin)
- 5. Some cause disease/pathogenic.
Types of Asexual Spores
**Two types of asexual spores in fungi?
--formed by the hyphae of one organism
; when these spores germinate, they become organisms that are genetically identical to the parent.
--Produced by mitosis & continued cell division
**Two types of asexual spores in fungi:
Conidiospore/conidium and Sporangiospore
": produced by sporangium
(inside a sac) which contains hundreds of sporangiospores; produced by Rhizopus (pinata...)-
- 2. "Conidiospores" (conidia "dustlike"): formed in a chain and then break off; NOT enclosed in a sac
- Conidia examples: Conidiophore and Arthrospores
Importance of Fungal spores:
- Blown by winds;
- easy to inhale;
- healthy immune system fights off most fungi doe
Three types of medically important fungi:
- 1. Zygomycota
- 2. Ascomycota
Phylum Zygomycota and examples?
Asexual reproduction: Sporangium (sac) bursts and produces sporangiospores
Sexual reproduction: Requires mating/meiosis to produce zygospores
Phylum Zygomycota Example: Rhizopus (black bread mold)
-Asexual and Sexual Reproduction
-Examples for each?
-Asexual reproduction: conidiophore produces conidia (dust like spores that float in air)
-Sexual reproduction: Requires mating/meiosis, Ascospores produced in ascus (a saclike structure)
**examples: Aspergillus (Asexual) and Truffles (sexual), Morel
-what kind of fungi, what does it produce?
-How are they formed?
-"club fungi"; produces mushroom
-Basidiospores formed externally on a base pedestal called a basidium.
-ex: Mushroom; Amanita (toxic mushroom)
- -Fungi with asexual spores only
- -Organisms recently classified
Mycosis & Types of Mycosis Infections (based on locations)
Mycosis: Fungal Infections
1. Cutaneous: Skin/epidermis, hair and nails
2. Subcutaneous: deeper layer of skin, usually occurs with wounds
3. Systemic: affects various body tissues and organs; usually starts reproduction in lunngs
4. Opportunisitic: takes advantage of weak immune system (due to meds, pregnant mothers, or HIV/immunocompromised people)
-Dermatophytes infect skin/hair/nails
-Cells w/ Keratin are infected (in hair and nails)
-Diagnosis: take a sample for microscopy analysis
Cutaneous Infections Examples: and preventions
- 1. Athlete's foot (tinea pedis): itchy blisters, cracked skin
- 2. Ringworm: itchy circular rash on body; NOT a worm (misleading)
- 3. Jock itch: itchy rash affects groin area
- -These Infections can be spread by objects (like towels)
- - Prevention: keep area dry; don't share towels
- -can be treated
Subcutaneous Fungal Infections
- -sporotrichosis in US: subcutaneous infection affecting gardeners/famers; small ulcers/lesions on hand
- -soil organisms (growth environment)--> gardening w/o gloves, microbes can enter wound and cause lesions
- -can be treated
- -prevention: wear gloves when dealing with soil
VALLEY FEVER: Microbe: classification, location and how is it spread...
- Microbe: "Coccidioides immitis" which causes coccidioidomycosis aka Valley Fever; dimorphic (two forms: yeast & mold)
- - classified in Phylum Ascomycota
- Spread by arthrospores
(hyphae-chain which breaks and is picked up in wind) in wind and dust which is then inhaled /: anyone can get the disease
-Activities that increase risk:
Being outside (dust in air) dir tbiking, construction, earthquake
Found in dry soil in American southwest, central/Southern Cali, Arizona, Northern Mexico. Mostly in Central valley
Valley Fever Symptoms, Diagnosis and Treatment:
- Possible Signs & Symptoms:Fever, Headache, cough, sore throat, chest pain (flu-like)
- -serious: meningitis
- -Rash or Joint pain like stiff neck
- Diagnosis and Treatment:
- -Serological test to detect antibodies (ONLY detects exposure doe)
- -Bronchoscopy: view trachea and bronchi
- -Surgery of nodule in lung, then culture or use microscopy
- -Treatment available: takes 6 months to recover
Valley Fever Disseminated Disease:
-Define Disseminated Disease
-what are the risk factors for VP Diss. Disease?
-Disseminated disease: spreads from neutral spots (lungs) to other parts of body. These risk factors cause disseminated disease:
-Adrenal corticosterioids (used to treat asthma, rheumatoid arthritis): immunosuppresant drugs that don't allow body to fight of pathogens that can cause VP
-Third trimester pregnancy: alters the way the immune system works
-immunocompromised: elderly, HIV pos, transplant patient who have to take immunosuppressant drugs
- Similiar to what other diseases?
- Where does it begin and can it spread?
Microbe: -"Histoplasma capsulatum"
: a dimorphic fungus that is found in soil, bird/bat doppings (nutrient rich soil)
Midwest US: Mississippi & Ohio Rivers (endemic)
- Airborne spores are inhaled; can cause sever disease beginning in lungs and even spread to lymp nodes (also disseminated)
- --> gives Flu-like/TB like symptoms (take TB test: turns out negative to eliminate)
- -->see how long it takes to go away: TB doesn't really go away
HISTOPLASMOSIS: Diagnosis Methods & Treatment
- Diagnosis Methods:
- -Serological test to detect antibodies (ONLY detects exposure doe)
- -take a tissue sample for culturing (blood, lymph node, lung or mucus)
- -Bronchoscopy: view trachea and bronchi
- -Surgery of nodule in lung, then culture or use microscopy
Opportunistic fungal infections:
and four examples?
Targets people with something that is altered in immune system; not normal healthy people (HIV+, Diabetics)
- 1. Candidiasis
- 2. Pneumonia
- 3. Mucormycosis
- 4. Aspergillosis
CANDIDIASIS (pg 606)
caused by "Candida albicans" (yeast) that causes yeast infection of the mouth and Vagina and can also cause systemic infections.
-signs/symptoms:Most candidial infections result in minimal complications such as redness, itching and discomfort. very common cause of vaginal irritation
-cause: Taking antibiotics (kill bacteria; eliminate good bacteria and now you have space for yeast to grow more) is one cause of yeast overgrowth (yeast can be found on healthy humans)
-sometimes called "thrush"
-Microbe: "Pneumocytis carinii/jiroveci"; causes pneumonia aka PCP (Pneumocystis Carinii Pneumonia)
-shows up in people who are HIV positive (opportunistic)
-this microbe is found on healthy humans
caused by: Mucor or Rhizopus (breadmold) (upper respiratory)
-opportunistic: Immunosuppressed patients at risk: (HIV--> Lung infections) and Diabetic patients at risk
-falls under what Phylum: Zygomycota (Rhizopus)
caused by Aspergillus (falls under Phylum Ascomycota)
-Fungus found on decaying vegetation: veggies in Fridge
-causes lung infection in HIV positive patients
-Active TB locations
-Mantoux Skin Test
-Diagnosis and Immunization
-Caused by Mycobacterium tuberculosis
; affects lower respiratory (lungs)
airborne respiratory droplets (coughing, sneezing) from close contact
Macrophages phagocytose Mycobacterium tuberculosis; 2
.if the bacteria isn't destroyed=> Latent infection
(not infection, dormant version of TB-still cough up sputum but no symptoms). 3. Active infection:
bacteria is transmittable w/ sputum. 4.
Bacteria eventually spreads to other body organs /:
: 90% have mild signs: fatigue, weight loss and 10% have noticeable symptoms: cough, fever, chest pain; bloody sputum and night sweats
Active TB locations:
South America, Africa, Asia, E. Europe. In US: homeless, health clinics, and prisions
- Mantoux Skin Test: Detects exposure to TB
- -Inject PPD:Purified protein derivative from Mycobacterium tuberculosis
- - Host's T Cells immune response determins pos/neg results; positive may mean prior vaccination, prev illness, present disease ==> requires x-ray test in addition
: Acid-Fast staining (mycolic acid retains carbolfuchsin) or sputum culture
- Immunization: No effective vaccine (prevents world elimination)
- --> "DOTS" (directly observed treatment, short-course): doctor makes sure patient takes meds to prevent drug resistance
- --> current TB control: "Stop TB strategy" which continues DOT
There are four drugs that you take at once. In order to avoid developing any resistance.
Metabolism & Two types
The chemical reactions in a cell.
- Two types:
- 1.Anabolism: make larger molecules from smaller ones; more complex.
- -Requires energy input
- Ex: photosynthesis (light --> Sugar)
- 2. Catabolism: chemical reactions that break down compounds and release energy.
- -The energy is used to make ATP.
- Ex: aerobic cellular respiration
- 1. Follow Carbons
- 2. Electrons collected by NADH, FADH2 (coenzyme type; electron carriers)
- 3. Collect Hydrogen Ions: H+
-where does it occur
-Bacterial products & How much
: the breakdown of glucose; occurs in cytoplasm
2 ATP (net gain), glucose, Pyruvate and NADH
1. One molecule of Glucose (6C)
is broken down into 2 Pyruvate (3C) molecules.
2. Two ATP are used
and 4 ATP are produced
3. Electrons are collected by NAD+
to become NADH
are used and make 2 NADH
(NADH: electron carrier
; carries 4 e-
4. NAD+ or NADH is then used in glycolysis
-final electron acceptor?
-Bacterial end products
- -No Oxygen needed; occurs anaerobically
- -occurs in cytoplasm
- -regenerates NAD+ from buildup of NADH in glycolysis
- -PYRUVATE=Final organic electron acceptor; accepts electrons from NADH (donator of 2 e's) to create NAD+ + H+ which can go back into glucose
- --> because pyruvate is organic, so are the products
- BACTERIAL END PRODUCTS: Lactic Acid,
- Ethanol, CO2
- 1. Pyruvate (organic final electron acceptor) gains electrons from NADH and becomes Lactic acid in some bacteria which produce yogurt, such as Lactobacillus (one organic product)
- 2. CO2 gas and Ethanol (2C)(organic compound) are produced by yeast fermentation (Ex: Saccharomyces cervisiae; bread, alcohol)
- --> One Pyruvate (3C) accepts 2 e's from NADH and to form NAD+ and H+ and then createing Ethanol (2C) and CO2 (1C)
(electron carrier) loses electrons and becomes NAD+
(electron carrier) which goes back into glycolysis cycle
-what kind of electron acceptor?
Oxidation (removing/collecting e's) and breakdown of chemicals; coupled to generation of ATP due to this process
-Requires an electron transportation system in membrane" molecules passing electrons to convert energy.
-Requires Inorganic final electron acceptor: definitely NOT pyruvate which is organic.
Two types: Aerobic and Anerobic.
AEROBIC CELLULAR RESPIRATION:
Still the breakdown of chemicals and ATP generation
- -- O2: final e- acceptor (organic)
- -- C6H1206 (glucose) + 6 O2 (oxygen) ---> 6 CO2 + 6 H20
-- animals/humans, yeasts, fungi, some bacteria (M. tuberculosis=aerobes)
ANAEROBIC CELLULAR RESPIRATION
-what kind of electron acceptor
-two examples: methanogens and E. coli
-- Uses inorganic final Electron acceptor
; obviously not Oxygen.
- Example 1: Methanogens (Archaea; found in intestines and cows)
- CO2 --> CH4 (methane gas)carbon dioxide is the final inorganic electron acceptor
- Example 2: E Coli:
- NO3- --> NO2 (nitrate-Inorganic elec acceptor; becomes nitrite).
- E. coli can either do aerobic, anaerobic respiration and fermentation o:
- Last less than a minute in chlorine...
what are the three Steps in aerobic cellular respiration ?
makes 38 ATP from 1 glucose molecule
- 1. Acetyl CoA
- 2. Krebs Cycle
- 3. Electron Transport System & Chemiosmosis
Aerobic Cell Respiration: Acetyl CoEnzyme A Step
One pyruvate from glycolysis (3C) and a Coenzyme A produce 1 "acetyl-coA (2c)" and one CO2 molecule (this reaction happens twice per glucose molecule--because it creates 2 pyruvates )
--> NADH is produced as NAD+ collects electrons; NADH used to make ATP later in ETS system
--> this steps occurs within cytoplasm of prokaryotes.
Aerobic Cell Respiration: Krebs Cycle
--> Oxaloacetate (4C) + 2C becomes citric acid- 6C (citrate) which eventually become 2 CO2 molecules
--> During each Krebs cycle: 2 CO2 are made, 1 FAD and 3 NAD+ collect electrons, and 1 GTP (ATP equivalent) is made.
--> Krebs cycle occurs twice per glucose molecule (2 pyruvate ) to produce FADH2 and NADH ( both goes into ETS system)
--> occurs in matrix of mitochondrion of eukaryotes
**SUMMARY OF PRODUCTS: 2 CO2, 3 NADH, 1 FADH2, 1 GTP**
Aerobic Cell Respiration:Electron Transport System & Chemiosmosis
molecules embedded in membrane that pass electrons to use energy; way to convert energy
a)FADH2 and NADH gives electrons to the ETS
(from krebs cycle; located in Plasma membrane of bacteria
; made of proteins and other membrane molecules)
b) H+ protons
are pumped outside
from inner membrane of mitochondrion
of eukaryotes so that there is more of a H+ concentration buildup on the outside.
c) O2 is an organic electron acceptor
that uses the energy from passing electrons to create water
d) ATP synthase enzyme
at the end of chain pumps the built up H+ concentration back inside
; these protons are used to bond ADP + Pi
(inorg phosphate) to create ATP
. The creation of 38 ATP max is made
- 1.Chemio: H+ ions are pumped out of the bacterial cell using the energy provided by electrons flowing down the ETS.
- 2. Osmosis:THEN the H+ ions flow into the cell through the ATP synthase and ATP & H20 is made.
- **Other notes:
- -ATP Synthase: Paul Boyer (1997) UCLA Nobel Prize
- -Chemiosmosis: Peter Mitchell (1978)
Genetics, Genome, Chromosome, Plasmids, Gene, Gene Expression
Genetics: study of heredity
Genome: all the genes in that particular organism
Chromosome: has most/all genes
Plasmids: circular; has few genes.
Gene: section of a chromosome; codes for a protein, usually a product
Gene Expression: using a gene needs transcription and translation
DNA and Structure
- type of replication?
-made up of ?
-semi conservative replication
-Double helix, Bases are hydrogen bonded with 5' end on top and 3' on bottom
- -loop domain sturcutre: DNA folded into bacterial cells
- -Supercoiling: twisiting, then extra twisiting on top of the double helix.
- -Replication: binary Fission
- -Nucleotide: made up of a phosphate group, a sugar, and base.
- -antiparallel: one strand moves one way and the other strand moves oppositely. One moves in a 5' direction so other stand moves oppositely in 3' direction.
- -semi-conservative replication: one new stand is paired with the old/original DNA strand
Semi Conservative Replication of DNA:
- --> make a copy of original DNA and uses them as templates
- --> Original DNA still present at end.
- --> occurs before binary fission so that two genetically identical cells can be made.
--> location: euk vs prok?
- -Eukaryotes Cells: Nucleus
- -Prokaryotic cells: Cytoplasm
2. A RNA primer by RNA Primase is added to start the DNA replication
- 1. The double stranded DNA is unzipped by the enzyme Helicase
- - going in right to left direction (<---) in a 3' to 5' direction
- -DNA built FROM a 5' to 3' direction meaning you add nucleotides in a 3' direction! (3' <---- 5' )
process; on the lagging strand
- 3. The DNA polymerase enzyme adds DNA nucleotides to the growing DNA strand.
- --> New DNA strand is complementary to the original DNA strand.
- 4. The replication fork is where the two strands of DNA have separated and new DNA synthesis is occuring.
5. The Ligase enzyme
link newly synthesized pieces of DNA together (okazaki fragments)
Assembly, Elongation, Termination
Make RNA complementary to DNA template; this RNA is a messenger-has genetic info; To use codes form mRNA to make proteins
1. Assembly: two subunits of ribosome, mRNA and tRNA w/ amino acids, Ribosomal RNA and Ribsomal tRNA
2. Elongation: covalent bonds form b/w anino acids.
3. Termination: at stop code.
- *in Translation*
- Group of 3 nucleotides in order that code for an amino acid OR STOP CODON!
- --> read 5' to 3' direction and always look at this strand to translate.
- --> editing mRNA: Get rid of non-coding "intron" regions b/w the exons (coding regions)
- DNA transcription: Messenger RNA created from dna template; dna sequence read by RNA
- *comes after Replication
The double stranded DNA is unzipped by the RNA polymerase
- 2. The RNA polymerase enzyme binds to the promoter site on the DNA to begin transcription
- --RNA Polymerase breaks the H+ bonds co complementary nucleotides; so that only one strand is copied.
- 3. The RNA polymerase enzyme adds nucleotides to the growing new messenger RNA strand. The new RNA is complementary to the DNA template strand.
- -->The mRNA contains the nitrogenous base Uracil (U) INSTEAD of Thymine (T)
. Transcription ends at the termination sequence/signal
of the DNA; when RNA polymerase reaches termination site of DNA and then the DNA strand rebinds while the RNA polymerase moves away
NEW mRNA takes a copy of the genetic code from the nucleus to the ribosome to be made/translated into a protein
DNA TRANSLATION STEPS
- Eukaryotes: Transcription occurs in nucleus
- Prokaryotes: Transcription and translation can happen at the same time
1. The subunits of the Ribosome
and the mRNA
all assemble together.
Each set of 3 nucleotides on the mRNA is a codon
, which codes for an amino acid.
The transfer RNA has an anticodon
which is complementary to the codon on the mRNA; its job is to bring aminoacids to the ribosome.
A peptide bond
is formed between 2 amino acids at the ribosomes.
is released from the ribosome.
This process of making a protein continues until a stop codon
is encounted and synthesis ends.
: STOP CODONS DON'T COUNT AS AN AMINO ACID**
**The sequence of the nucleotide bases in each codon is significant: 5' ATG is not the same a 5' GTA**
More Translation Notes:
-tRNA and it's relation to mRNA codons
: IN cytoplasm/ribosomes; mRNA leaves nucleus, goes into cytoplasm and make proteins out of amino acids
mRNA codons-->tRNA anticodons: mRNA is copy of DNA
- transfers amino acids from cytoplasm to ribosome. Grabs its amino acid, bonds to ribosome then drops off aminoacid (trucks) and repeats this process.
- Each tRNA has a specific anticodon (bonds to codon of mRNA) untill it gets to a stop sequence.
- Eukaryotes and Prokaryotes:
- Differences in DNA replication, Transcription and Translation
- - Replication: nucleus
- - Transcription occurs in nucleus and THEN mRNA moves to cytoplasm for translation
- -modifies mRNA by splicing, 5' end caping, and adding polyA tail
- -Replication: Cytoplasm/nucleoid
- -Transcription and translation can happen at the same time; occurs in cytoplasm
General Characteristics of STI:
1. Mode of transmission
2. Affected Body Parts
Mode of transmission: Sexual Activity
Affected Body parts: Reproductive organs
Prevention: Abstincence, monogamy with healthy partner, condoms
- Microbe info: Treponema pallidum
- -shape: spirochete
- Transmission Mode:
- contact w/ sore or rash
- 1. Primary stage: small hard painless sore at infection site
- 2. Secondary stage: rash on hands/feet, hair loss, other signs and symptoms
- 3. Latency: no signs S:
- 4. Tertiary stage: about 15% of untreated cases; affects kin or CNS or aorta D:
- Congenital Syphilis:-Mother to baby transmitted, bacteria crosses placenta during latency.
- -Affects neurological system, the mothers can be treated and cured.
Darkfield microscopy/fluorescent antibody detection (primary stage) and Serological test (Secondary test)
Infected Parts of Body
- Microbe: Neisseria gonorrheae-diplococcus
- -gram negative (pink)
- -has fimbriae
Infected Parts of Body:
- Transmission: Infected mother can pass GC to newborns during childbirth.
- -Antibiotics used to treate eyes of newborns to prevent GC
urethra, pharynx, rectum, eyes, cervix, uterus, Fallopian tubes
- -Men: Frequently SYMPTOMATIC: pain when urinating, discharge
- -Women: frequently ASYMPTOMATIC or...reddened cervix, abdominal pain, pain when urinating, disrupted menstrual cycle.
- Female complications:
- 1. Pelvic inflammatory disease: spread of disease to fallopital tubes/ovaries/uterus. Caused by gonorrhea or chlamydida.
- --signs/symptoms: asymptomatic or fever/abdominal pain
infection of the fallopian tubes; severe form of PID
3. Infertility and Ectopic Pregnancies
Antibiotics or Cephalosporin.
Complication for Women
- Microbe: Chlamydia
- -Intracellular bacteria
- -very small (NOT visible in light microscope), infects the same cells as GC
- -common cause of non-gonococcal rthritis
- -Patients are asymptomatic
- Complications for Women:
- 1. PID (Pelvic Inflamm. Disease)spread of disease to fallopital tubes/ovaries/uterus. Caused by gonorrhea or chlamydida. --signs/symptoms: asymptomatic or fever/abdominal pain
- 2. nonculture test (DNA detection)
- **gram stain is useless because it is too small
Antibiotics like Doxycycline
Ways to Diagnose a Bacterial Infection
- 1. Culturing
- 2. Gram Stain
- 3. Detect DNA
- 4. view WBC's
- 5. Detect antibodies in serological test
Giardia Lambia Cysts:
--> what is a cyst?!
--> where is it found, how is it transmitted?
inactive form, non-motile and resists DISINFECTION.
-oval shape, 4 nuclei
Shed in Feces, transmitted in fecally contaminated water and by oral contact of food.
--> what is a Trophozoite?
--> common where?
- Trophozoite: Active-Feeding form
- Most common in duodenum; also found in stool
- Has two nuclei with karyosomes and axostyle-a line in the middle of the cell and 8 flagella
Plasmodium Falciparium (ring stage)
- Transmitted by mosquitos;
- cause malaria: fatal vessel obstruction and thrombosis.
- --sporozoite transmitted my mosquito bite
- --reproduces in liver THEN RBC's
- Ring stage-parasite in RBC.
Most found in vaginal area, transmitted sexually- STD: trichomoniasis