Lab Exam 2 Study Guides

Know how to identify all parts of a living onion.

-Foliage leaves

-Scale Leaves

-Adventitious roots

What is the function of the foliage leaves and scale leaves on the onion?

Photosynthesis. The scale leaves are for protection.

Know how to identify all parts of a root tip model.

-Epidermis

-Primary Vascular Tissue

-Root Hair

-Root tip

-Root cap

-Meristematic region

-Region of elongation

What is taking place within a meristematic region of a plant root?

Mitosis

What is the function of a root cap on a plant root?

-Sending out a lubrication so it can go through the soil easier.

-It also is there for protection

Know how to identify the interphase stage of mitosis

-majority of cell life

-primary growth of cell

Know how to identify the prophase stage of mitosis.

-Nuclear envelope forms

-Spindle apparatus forms

-Centrioles move in animal cells

-Aster form in animal cells

Know how to identify the metaphase stage of mitosis.

Chromosomes line up on metaphase plate

Know how to identify the anaphase stage of mitosis.

-Sister chromatids separate by being pulled apart to either side

Know how to identify the telophase stage of mitosis.

Chromosomes are on either side of the cell and try to pull apart

What is the function of the spindle? What are the structural components of the spindle?

-Movement and pulling them apart

-Made of microtubules

Chromosomes move to the middle of the spindle during what phase?

Metaphase

During which phase do the cells separate?

Telophase

During which phase do chromosomes first become visible?

Prophase

Does cell growth occur during interphase or mitosis?

Interphase

Does the nuclear membrane dissolve during interphase or mitosis?

Mitosis

Are chromosomes distributed equally to daughter cells during interphase or mitosis?

Mitosis

Does DNA synthesis (replication) occur during interphase or mitosis?

Interphase

Does the cytoplasm divide during interphase or mitosis?

Mitosis

What is the end product of mitosis?

2 diploids, going to have 46 chromosomes (identical)

Know how to identify all parts of a complete flower (for lab exam two).

What are the non-reproductive parts of a flower mentioned in the lab nine lecture?

Sepal, petal, perianth

When can a flower be called "complete?"

-When it has all male and female parts it has to have all non-reproductive parts.

-Everything has to be present.

What are the male parts of a flower?

Stamen, filament, anthur

What are the female parts of a flower?

Pistil, (ovary, stigma, etc.)

Regarding flower anatomy, what is the definition of a (a) whorl, (b) receptacle, (c) pedicel?

(A): Whorl- represents the different levels of the flower being complete. Stand for each part.

(B): Receptacle- base that attaches the reproductive and nonreproductive parts.

(c): Pedicel- stem-like portion, which isn't always present in each plant. Can be directly attached

What is a sporangia? What is the difference between microsporangia and megasporangia?

-Has germ-line cells, which creates gametes, and lead to diploids going to gametes.

-Difference is micro means male and therefore makes pollen. The megasporangia is female with eggs

What are meiospores?

-Things that are going from interphase into becoming gametes.

-They are diploids eventually becoming haploid, and becoming spores. They are like pre-spores

What are the number and type of cells that result from meiosis vs. mitosis.

-Meiosis results in 4 non-identical haploid daughter cells

-Mitosis results in 2 diploid daughter cells

How do the genetic contents of cells resulting from mitosis and meiosis differ?

-Mitosis has genetically identical cells and meiosis has non-identical cells.

-Mitosis is diploid and meiosis is haploid.

If a diploid cell containing 28 chromosomes undergoes meiosis, how many chromosomes will each daughter cell have?

14

How are mitosis and meiosis similar or different?

-They both begin with a diploid cell.

-Difference between is that meiosis goes through two divisions while mitosis goes through one.

Know how to identify prophase I of meiosis (for lab exam two).

-Chromosomes cross over

-chromosomes thicken

-homologous chromosomes pair up

Know how to identify metaphase I of meiosis (for lab exam two).

Chromosomes line up in the middle in pairs

Know how to identify anaphase I of meiosis (for lab exam two).

Chromosomes are being pulled to either side of the cell by spindle fibers

Know how to identify telophase I of meiosis (for lab exam two).

Chromosomes are on opposite end and new nuclei form on each side surrounding chromosomes

Know how to identify prophase II of meiosis (for lab exam two).

Chromosomes condense

Know how to identify metaphase II of meiosis (for lab exam two).

Chromosomes line up in single file line

Know how to identify anaphase II of meiosis (for lab exam two).

Chromatids are pulled to either side of the cell

Know how to identify telophase II of meiosis (for lab exam two).

Chromosomes are on either side and are forming new nuclei surrounding the chromosomes

What is the difference between a viroid, prion, and virus?

-Viroid: makes RNA (plants)

-Prion: makes infected proteins

-Virus: Subatomic affected, made by DNA

What can be the components of a virus and what are their functions?

-Envelope: made of fats/lipids and are there for extra protection (not all some have)

-Spike:

-Capsid: made of protein and coat it; responsible for protecting virus

-Nucleic acid: RNA or DNA

What does it mean if a virus is "naked?"

Has no envelope

What occurs during the lytic cycle of a virus (in detail as discussed in lab)?

-Attachment

-Entry of phage DNA & degradation of host DNA

-Synthesis of viral genomes and proteins

-Assembly

-Release

What occurs during the lysogenic cycle of a virus (in detail as discussed in lab)?

1. Phage attaches to host cell and injects DNA

2. Phage DNA circularizes and enters lysogenic cycle

3. Phage DNA integrates within the bacterial chromosome by recombination, becoming a prophage

4. Lysogenic bacterium reproduces normally

5. Prophage may excise from bacterial chromosome by another recombination event, initiating a lytic cycle

What is the definition of a virus?

A submicroscopic pathogen

What are viruses doing before they infect a host? What is their only goal?

-Before infecting they wait in crystalline

-Goal is to reproduce

What does a virus have to do to "live" or reproduce? Why (explain)?

Has to enter and utilize another cell because it doesn't have the machinery to live on its own

What type of microscope, in the 1930s, had to be invented in order to observe viruses? What was its magnification?

-Electron microscope

-7,000 times

The AIDS virus has a core that contains _____________, it's a package of _____________ enveloped in a set of ______________ that allow the virus to utilize the cell for its own replication because it cannot function independently (cannot multiple independently).

genetic information, nucleic acid of genetic material, proteins

How are the genes of a virus protected?

A thin shell studded with molecules

The red plague that affected humans during the Peloponnesian war in the 5th century BC was probably due to which virus(es)? What virus was the scourge of the Middle Ages? What virus was mentioned in the Egyptian tombs when they were opened?

-Typhus, scarlet fever, or measles

-Smallpox was scourge

-Polio from egyptian tombs

One of the worst natural disaster in recorded history was caused by a virus. Which virus and what year? How many people were killed world-wide? How did this virus spread so easily?

-Influenza in 1918

-20 million people died

-During WWI allied troops in Northern France exchanged lethal strain of flu that spread around the world

What is the definition of a vaccine? What was the first vaccine created to kill?

-Vaccine: A virus simulating a immune response

-Small pox first vaccine to kill

How does your body kill a virus or bacteria? Understand the recognize, destroy, and memory prompts given in the video.

-Kills by using antibodies to bind to the surface of a virus/bacteria and flag it for death

-Destroy: body's white blood cells move into destroy virus infected cells

-Recognize: body immediately recognizes a virus if it enter again

-Memory: body remembers any viruses or fake viruses to protect you

Influenza viruses are usually grown in the lab in what organism?

In the egg and chicken cells

How did the influenza virus find a way around vaccines and your immune system?

By mutating

Why are RNA viruses a problem?

RNA viruses change all the time since they don't copy like DNA viruses

Why is it so hard to predict the influenza that will infect a specific area, region, or country each year?

A new strain comes from a different source every year

In 1955, Dr. Salk changed medicine by creating the polio vaccine. This vaccine was different from previous smallpox vaccines. How was it different?

It could immunize against the virus without experiencing infection

How does the rotavirus affect a person physically? How many children are killed a year by this virus?

-Attacks lining of small intestine, child develops severe diarrhea

-5 million children killed a year

Why does the rotavirus mainly affect poorer tropical countries and areas?

-Sanitation is hard

-The virus is stable which makes person-to-person transmission easier

In 1967, what disease did doctors and scientists want to eradicate from the world? What country had the last recorded smallpox case? What was the year of the last recorded smallpox case?

-Smallpox

-Somalia

-1978

Where is the smallpox virus still around? (there are two places)

-Moscow

-CDC in Atlanta

In 1519, Cortez invaded Mexico and conquered millions of Aztecs. What disease is more responsible for this than his horses, guns, and infantry?

-Smallpox

Experts believe what percent of species on earth are unknown to us?

90%

Arboviruses are carried by which organisms? How are they found?

-Insects that live in tree pots and on the forest floor

From mosquitos alone, how many strains of viruses have been found within the South American lab?

40 strains

Dengue fever is transmitted from which organism? What is the nickname of dengue fever? How is this carrier organism (of the viruses) spreading around the world?

-Transmitted from Asian tiger mosquito

-Breakbone fever

-Shipments of used tires

How did Hantavirus spread during the Korean War and the United States?

From urine of field mice that lived in rice paddies

AIDS is caused by which virus? How did it slowly get into the human population?

-HIV

-mutation of monkey virus centuries ago

Does HIV, once within a human, instantly kill its host? Why was it difficult to find within the body?

-Doesn't kill instantly

-Uses property or retrovirus RNA to make a DNA copy of itself and hides in host cells

What year and in which country was Ebola first categorized?

Sudan and Zaire in 1976

How can viruses be used to help cure or ease the symptoms of diseases?

Breaking into a cell to change inborn defects in genetic code

Know how to identify coccus bacteria.

Know how to identify spirillum bacteria

Know how to identify spirochete bacteria

Know how to identify bacillus bacteria

Know how to understand and comprehend a law of tolerance graph.

Which statement does not describe the steps to the bacterial UV light experiment?

-First spread E. coli all over the petri plate

-Cover one half of the petri plate to protect against UV light

-Expose the other side to UV light for whatever amount of time needed

-After covering up the plater and incubate overnight. -Repeat for all

Which statement describes the experimental design for the Kirby-Bauer sensitivity assay?

-Use little paper discs that are soaked in antibiotics.

-Take the discs and pit them on a petri dish that is thick with bacteria.

-The antibiotic diffuses into the augur while the plate is incubated and stops growth.

-Concentration decreases as you go farther from the disc. -Cover the dish fully with a thick layer of bacteria and bacteria grows up to a lawn.

-Putting them on an incubated petri dish we can see where antibiotics stopped bacteria from growing.

What is the shape of (a) coccus, (b) bacillus, (c) spirillum, or (d) spirochete bacteria?

-(a) coccus: circular

-(b) bacillus: rod shaped

-(c) spirillum: spiral

-(d) spirochete: cork screw

What is the difference between strepto- and staphylo- bacteria (morphologically speaking)?

Strepto means chains of and staphylo means clusters, so different shaped bacteria

What is the definition of the "law of tolerance?"

Law of tolerance is an area to figure out what is the best optimal conditions that bacteria can grow

How can the law of tolerance be applied to living organisms? (we will mention three answers to this question)

-it's the fact that every single organism too much or too little of certain environmental factors can be very limited.

-ecological minimum and maximum

-when you exceed extremes, it will stress and kill an organism.

What are we trying to observe when completing the Shelford's law of tolerance experiments?

Trying to observe which antibiotics are going to be the most effective against gram positive and gram negative bacteria. MISSING ONE THING.

What amount of UV light is harmful to E. coli according to your lab twelve experiment?

2 minutes of UV experiment can kill all bacteria. After 30 seconds it took effect.

What do your UV light experiment results tell us about E coli's ability to survive on UV (light) exposed surfaces?

This tells us that its ability to survive on UV exposed surfaces is minimal and only a small fraction of bacteria could be able to grow.

What happens to bacteria's DNA when it is exposed to UV light?

UV light causes 2 adjacent T bases to band with each other, forming thymine dimers. Thymine dimers prevent DNA from base read correctly. If a cells DNA develops too many thymine dimers, the cell will die.

How are the antibiotics placed into the petri dish for the Kirby-Bauer method during your lab twelve experiment? (Obviously, you do not just throw a pill inside)

uaw little paper discs that are soaked in antibiotics. Take the discs and put them on a petri dish that is thick with bacteria.

What is a zone of inhibition?

clearings around the antibiotic discs. The bacteria are only susceptible to some kinds of antibiotics.

How does one measure the susceptibility of a bacterial species to an antibiotic using the Kirby-Bauer method?

you have to measure the zone of inhibition to determine the susceptibility.

Which type of bacteria is more susceptible to antibiotics in general based on your lab twelve results?

Gram negative

Are all bacteria bad?

No

Regarding the bacteria that colonizes your skin, it is good or bad? Explain.

Some are beneficial and can help keep harmful straun and other types of pathogens from growing.

What are ways bacteria can be beneficial?

Bacteria in your digestive system can help break down food and produce vitamins. Some types of bacteria are used in producing some foods we eat.

Why do we have to be careful about which ones and how many antibiotics we take?

Antibiotics can harm some of the good bacteria as well

Do antibiotics work on viruses?

No because viruses are pathogens that are not made of cells

What are the three main types of bacterial shapes?

-Coccus (sphere)

-Bacillus (bacilli; rod shaped)

-spirillum (spirilla; spiral shaped)

What does it mean bacteria can be heterotrophs or autotrophs?

-Heterotrophs: they consume or feed on some organic matter

-Autotrophs: they can make their own food