Lab Exam Flashcards
1
Q
Know what a red blood cell looks like within a hypotonic, hypertonic, and isotonic solution.
A
Hypertonic (shriveled), isotonic (normal), hypotonic (puffed up and bursting)
2
Q
What are erythrocytes?
A
Erythrocytes are red blood cells without a nucleus.
3
Q
How should red blood cells react to hyperosmotic, hypoosmotic, and isosmotic solutions?
A
- In hyperosmotic solutions, red blood cells crenate (shrink) due to salt.
- In hypoosmotic solutions, red blood cells lyse (explode), due to the excess water coming in.
- In isotonic solutions, the red blood cells are stable because the solution is balanced.
4
Q
What occurs during the lysis or hemolysis of a cell?
A
During lysis or hemolysis, the cell is exploding since water is coming in and making the cell expand. Hemolysis can’t be reversed.
5
Q
What happens to a cell when it is crenate?
A
When a cell is crenate it shrinks due to the salt in the solution.
6
Q
Which is not a step to prepare a tap water Elodea slide?
A
Obtain a clean glass slide, hypertonic solution, and lab gloves. Put on lab gloves and retrieve Elodea sp. culture. Make a wet mount of Elodea leaf. Observe the condition of the leaf with the scanning, low, and high-dry objectives. The leaf should be turgid. Draw several fully hydrated leaf cells that are visible with a high-dry objective.
7
Q
What is plasmolysis?
A
Plasmolysis is the cell losing water. All the organelles are dying, and the chloroplasts bundle to the middle b/c no central vacuoles in the cytoplasm.
8
Q
Which statement describes turgor?
A
Turgor is pressing a lot of pressure on the cell wall.
9
Q
Which statement describes turgor pressure?
A
Turgor pressure is pressing a lot of pressure on the cell wall.
10
Q
Why does water leave a plant cell when it is placed in a hypertonic solution?
A
Water leaves the plant cell in a hypertonic solution because it wants to move towards areas with high solubility, or solution concentration.
11
Q
What substances keep the plant cell turgid?
A
high solute concentration in the cell and water.
12
Q
How does one clean and handle a microscope?
A
Grasp the microscope with one hand and support it at the base with the other, do not touch lenses with your fingers, do not use paper towels or cloth to wipe the lens (use lens paper), do not allow liquid near the microscope.
13
Q
How do you find the magnification of our light microscopes we use within the lab (i.e.
how is it calculated)?
A
You read the objective lens and multiply it by 10.
14
Q
What are the three most common magnifications to find on a light microscope?
A
X40, x100, x400
15
Q
When does one make a wet mount?
A
You make a wet mount when you are focusing on a direct examination of living specimens/non-living materials for a short time; this can determine the size and shape relationship, motility, and reactions to various chemicals of an organism.
16
Q
How does one make a wet mount?
A
Materials: glass slide, coverslip, elodea, bottle with water.
- Clean slide
- Take some water and place 2-3 drops on a glass slide
- Pick out a leaf from the elodea plant and CAREFULLY & GENTLY place it on the water drops.
- Place the coverslip carefully & slowly/gently
- Gently push down on the coverslip
17
Q
When does one use oil immersion?
A
Oil Immersion - allows the highest magnification to be used due to the refractive index of the oil to be the same as the lenses.
- The oil acts as an additional lens in the system and prevents the loss of necessary light rays
- Can be used on dead materials and organisms
18
Q
How does one use oil immersion? (watch the video on the PowerPoint for all of the
steps)?
A
You use oil by raising the stage until the oil immersion objective touches the slide but no further than the point where it just touches and this is going to be done using the coarse focus of the microscope and slowly turning it away from you which raises the stage and very slowly getting our eyes down where we can see what’s happening and watch between the interphase lense and the drop of oil so we slowly raise the stage seeing the drop of oil and when the lens hits the drop of oil you see the light scatter. Use fine focus to get the image where you can see it clearly. Adjust the eyepiece and slowly turn it away from you. Concentrating until you can see some color.
19
Q
Know how to identify all parts of a living onion
A
Foliage leaves: Leaves on top
Scale Leaves: The Dead Leaves on the Side
Adventitious roots: The bottom roots
20
Q
What is the function of the foliage leaves and scale leaves on the onion?
A
Foliage leaves - responsible for photosynthesis
Scale leaves - dead; used to protect onion from decomposition
21
Q
What is taking place within a meristematic region of a plant root?
A
All mitosis takes place here - it is above the root tip
22
Q
What is the function of a root cap on a plant root?
A
Protects root tip and secrets a lubricant that allows it to move through the soil
23
Q
Know how to identify the interphase stage of mitosis.
A
Cell Growth Occurs, replicating its DNA
24
Q
Know how to identify the prophase stage of mitosis.
A
Chromosomes first become visible
25
Know how to identify the metaphase stage of mitosis.
Chromosomes move to the middle of the spindle
26
Know how to identify the anaphase stage of mitosis.
Chromosomes break; sister chromatids move to opposite ends of the cell
27
Know how to identify the telophase stage of mitosis.
The Cells Finally Separate
28
What is the function of the spindle? What are the structural components of the spindle?
The Spindle separates the chromatids during mitosis to opposite sides of the cell. It is made up of spindle fibers and microtubules.
28
What is the function of the spindle? What are the structural components of the spindle?
The Spindle separates the chromatids during mitosis to opposite sides of the cell. It is made up of spindle fibers and microtubules.
29
Chromosomes move to the middle of the spindle during what phase?
Metaphase
30
During which phase do the cells separate?
Telophase
31
During which phase do chromosomes first become visible?
Prophase
32
Does cell growth occur during interphase or mitosis?
Interphase
33
Does the nuclear membrane dissolve during interphase or mitosis?
Mitosis
34
Do chromosomes distribute equally to daughter cells during interphase or mitosis?
Mitosis
35
Does DNA synthesis (replication) occur during interphase or mitosis?
Interphase
36
Does the cytoplasm divide during interphase or mitosis?
Mitosis
37
What is the end product of mitosis?
Cytokinesis - Two identical daughter cells are made
38
When can a flower be called “complete?”
Both female and male parts
39
What are the male parts of a flower?
Stamen (made up of filament and anther)
40
What are the female parts of a flower?
Pistil (stigma, style, ovary, and ovule)
41
Regarding flower anatomy, what is the definition of a (a) whorl, (b) receptacle, (c)
peduncle, (d) inflorescence, and (e) pedicel?
- Floral organs’ formation in a circle
- The tip of a modified stem
- The modified stem itself
- A cluster of flowers
- The modified stem where the receptacle is found if a cluster/inflorescence is found
42
What is a sporangia? What is the difference between microsporangia and megasporangia?
Sporangia- diploid part of the plant that is the reproductive area that produces gametes
- Microsporangia - male reproductive organs that make sperm
- Megasporangia - Female reproductive organs that make sperm
43
What are meiospores?
The cells that go through meiosis and eventually turn into gametes
44
What are the number and type of cells that result from meiosis vs. mitosis.
Mitosis has 2 identical diploid cells. Meiosis produces 4 haploid cells
45
How do the genetic contents of cells resulting from mitosis and meiosis differ?
Meiosis has 4 cells at the end while mitosis has 2
46
If a diploid cell containing 28 chromosomes undergoes meiosis, how
many chromosomes will each daughter cell have?
14
47
How are mitosis and meiosis similar or different?
- Similar - 2 new cells are produced at the end of mitosis and meiosis 2.
- Differences - meiosis has 4 cells at the end while mitosis has 2
48
What is the difference between a viroid, prion, and virus?
- Viroid - small circular naked RNA molecule capable of infecting the host
- Prion - INfectious proteins that misfold your proteins
- Virus - small, noncircular infectious DNA or RNA cored(?), non-living.
49
What can be the components of a virus and what are their functions?
- Capsids - protein-based covering of nucleic acid core
- Core of virus - replicates in a similar manner to us in our cells; RNA
- Envelope - Lipid bilayer; absorbs outside layer of host’s cells
- Spikes - proteins that allow the virus to attach itself to a host cell
50
What does it mean if a virus is “naked?”
Ability to attach themselves to the host cell with spikes not present in an envelope
51
What occurs during the lytic cycle of a virus (in detail as discussed in the lab)?
In the lytic cycle, the whole cycle will be complete within an hour.
52
What occurs during the lysogenic cycle of a virus (in detail as discussed in lab)?
The virus will lay dormant and only replicate when the host cell replicates
53
What is the definition of a virus?
A submicroscopic pathogen
54
What are viruses doing before they infect a host? What is their only goal?
They wait in a crystalline form somewhere between life and death. Their only goal is to reproduce by waiting for a living host
55
What does a virus have to do to “live” or reproduce? Why (explain)?
To live, it enters and utilizes another cell because it doesn’t have the machiner to live on its own
56
What type of microscope, in the 1930s, had to be invented in order to observe viruses? What
was its magnification?
Electron microscope at 7000 times magnification
57
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, proteins
58
How are the genes of a virus protected?
Thin shell studded with molecules that enable it to dock with a target cell and work its way inside.
59
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?
The red plague was likely typhus, scarlet fever, or measles. The scourge of the Middle Ages was smallpox. Polio was inside Egyptian tombs
60
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?
The Influenza pandemic of 1918 killed at least 20 million people world-wide. The strain spread a lot because of the war. When allied forces met in northern France, the exchanged a lethal strain of the flu. This then went from France to the US.
61
What is the definition of a vaccine? What was the first vaccine created to kill?
A virus stimulating an immune response. The first vaccine was small pox.d
62
How does your body kill a virus or bacteria? Understand the recognize, destroy, and memory prompts given in the video.
- Your body kills virusis or bacteria with your immune system.
- Recognize: Antibodies flag them for destruction
- Destroy: white blood cells destroy viruses or infected cells.
- Memory: once destroyed, the memory recognize that virus if it enters your body again and protects you, which is how vaccines work.
63
Influenza viruses are usually grown in the lab in what organism?
Chicken embryos
64
How did the influenza virus find a way around vaccines and your immune system?
By mating, it changes the way it looks so the immune system doesn’t recognize it
65
Why are RNA viruses a problem?
RNA viruses do have a low frequency of mutations because they don’t have a system that corrects errors. Because they mutate regularly, you need a new vaccine every year.
66
Why is it so hard to predict the influenza that will infect a specific area, region, or country each year?
The influenza strain changes frequently because it can cross between species and the strain changes each time this happens. Ex: Ducks with the influenza virus pop in the water. Then, pigs drink that water and the influenza genes mix to make a new strain.
67
In 1955, Dr. Salk changed medicine by creating the polio vaccine. This vaccine was different from previous smallpox vaccines. How was it different?
The vaccine contained salt-killed polio. This virus altered the immune system without making the person sick.
68
How does the rotavirus affect a person physically? How many children are killed a year by this virus?
Rotavirus attacks the lining of the small intestine. As the body tries to flush the irritant away, the child develops severe diarrhea. It kills over 5 million children per year.
69
Why does the rotavirus mainly affect poorer tropical countries and areas?
It is water-borne and poor communities typically have 1 water source. If a child has diarrhea in the river, it spreads the virus more and locals bave no choice but to drink from that water because its the only source. It also spreads between people and poorer areas lack proper sanitation
70
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. The last record of smallpox is found in Somalia. The last recorded case was in 1978.
71
Where is the smallpox virus still around? (there are two places)
In moscow and in the Center of Disease Control in Atlanta
72
In 1519, Cortez invaded Mexico and conquered millions of Aztecs. What disease is more
responsible for this than his horses, guns, and infantry?
Smallpox
73
Experts believe what percent of species on earth are unknown to us?
90%
74
Arboviruses are carried by which organisms? How are they found?
Carried by insects that live in treetops and forest floor. Researchers brought them while in liquid nitrogen and sought them under a microscope.
75
From mosquitos alone, how many strains of viruses have been found within the South
American lab?
40
76
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?
Asian tiger Mosquito. It is spread through shipments of used tires around the world. It is also called breakbone fever.
77
How did Hantavirus spread during the Korean War and the United States?
It spread from the urine of field mice in rice paddies
78
AIDS is caused by which virus? How did it slowly get into the human population?
HIV. It got into the population through a mutation of a monkey virus and then transferred to people through rituals using monkey blood. Then it spread as civilization expanded and as transportation became possible.
79
Does HIV, once within a human, instantly kill its host? Why was it difficult to find within
the body?
It first kills the immune system. Then it makes a DNA copy of tiself which goes to the host and integrates itself with the cells’ DNA. It can stay silent so it is difficult to find.
80
What year and in which country was Ebola first categorized?
In Sudan and Cairo in 1976
81
How can viruses be used to help cure or ease the symptoms of diseases?
Researchers can use a virus’s ability to break into a cell to change inborn defects in the genetic code. For example, people with cystic fibrosis that are missing a gnee can be injected with a cold virus whose genetic code is changed to contain the cure for cystic fibrosis
82
Know how to identify coccus bacteria.
Round or spherical shaped
83
Know how to identify spirillum bacteria
Curved shaped long
84
Know how to identify spirochete bacteria.
Spirally twisted snake.
85
Know how to identify bacillus bacteria.
Rod shaped
86
Which statement does not describe the steps to the bacterial UV light experiment?
Environment: The petri dishes will be inoculated at 37 degrees C. The lamp uses 2 15 watt bulbs and 220 volts and the wavelength is 257nm, uvc
- Spread E-coli over a petri dish
- Cover half of the petri dish to protect it against the UV light
- Expose the uncovered side to UV light for 15 seconds
- Cover the plate and let it incubate overnight for 22 hours
- Repeat steps 1-2 to a new dish
- Expose the uncovered side to UV light for 30 seconds
- Cover the plate and let it incubate for 24 hours
- Repeat steps 1-2 to another new dish
- Expose the uncovered side to UV light for 60 seconds
- Cover the plate and let it incubate for 24 hours.
- Repeat steps 1-2 to another dish
- Expose the uncovered side to UV light for 120 seconds
- Cover the plate and let it incubate for 24 hours
87
Which statement describes the experimental design for the Kirby-Bauer sensitivity assay?
- Put on gloves and gather tweezers, sterile cotton swabs, a marker, six discs each containing a different presoaked antibiotic, a plate with single colonies, a blank plate, and a container for waste.
- Label the bottom of the plates
- Take out a sterile swab and draw a black spot next to the tip to help you locate the side that is inoculated with bacteria
- Inoculate a single colony by touching a colony with the tip of the swab
- Inoculate a lawn on the blank plate by spreading the bacteria evenly, covering the whole plate both horizontally and vertically.
- Discard the cotton swab in the waste container.
- Divide the plate into sixths
- Use tweezers to place one antibiotic disc on its own section of the plate
- Gently tap the disc to stick it to the auger
- When placing the disc, use the lid to shield the plate from contamination, and if it falls out of the tweezers, leave it where it falls.
- Do steps 9-11 5 more times on different inoculated dishes while checking to make sure you are using different antibiotics.
- Place the 6 plates upside down in a 37-degree celsius incubator for 24-48 hours (or as instructed by your teacher)
88
How many mass extinctions in the history of the planet?
5
89
What is a common characteristic of all five mass extinctions?
A mass increase in CO2
90
The ocean is absorbing huge amounts of carbon dioxide. What has been the result?
The CO2 Reacts with water to form carbonic acid and because of this, each year the ocean is becoming more acidic. Different varieties of creatures will simply dissolve into the acid ocean.
91
Methane is a very potent greenhouse gas. What type of agriculture produces large
quantities of it? What percent of agricultural land is used for these organisms?
Livestock produces large quantities of methane. The video dives into mostly cows. ¾ or 75% of agricultural land is used for livestock.
92
Phytoplankton produces half of the oxygen we breathe. How much have these organisms
decreased in population in the last 50 years? What would happen to aquatic ecosystems if
phytoplankton became extinct?
They decreased by 40%. If they become extinct, everything else fails because all species are connected.
93
There are approximately 7000 species of amphibians. How many are endangered?
All of them
94
There are approximately 340 species of turtles in the world. How many are under threat?
Half of them
95
What probably led to the “great dying” during the Permian Period?
Methane gas
96
What organisms can be considered “algae?”
Any protist that is photosynthetic and has some form of chlorplast
97
What is the one main difference between unicellular and multicellular algae?
One cell vs having multiple cells
98
Which statement describes the characteristics of the species Euglena we discussed in class?
- Can have cell wall covered by pellicle (made of protein)
- Has eyespots, or stigma, which allows them to sense where light is
- Can have contractile vacuoles that pump water out of the cell. It keeps out excess water to prevent lysis
99
Referring to the Dinoflagellates, how many flagella do they have? What is the function of
their thecae? Why can they be considered dangerous to humans?
They have 2 flagella. The thecae is a term for outside layer used for protection. They’re dangerous because they have red tides throughout the year and if consumed, even through another organism such as shrimp that at from the toxic blooms, you can get massively sick and potentially die.
100
The color of all chloroplasts found within species of Phylum Rhodophyta is _____.
Fill in the blank.
red
101
Why is it this color (the species within Phylum Rhodophyta)? (the answer involves its
chlorophyll pigments)
It’s red because they use chlorophyll a and d. Phycoerythrin, an accessory pigment causes them to stay this color.
102
Most species of diatoms have frustules. What are frustules? What type of chlorophyll do
they utilize?
Frustules are silica walls which are used for protection. They use chlorophyll a and c
103
The color of all chloroplasts found within species of Phylum Chlorophyta is _______.
Fill in the blank.
green
104
Why is it this color (Phylum Chlorophyta)? (the answer involves its chlorophyll
pigments)
It uses chlorophyll a and b, which reflect green light
105
Referring to the Hydrodictyon: what geometric shape repeats throughout the specimen?
hexagons
106
Referring to the Volvox: are daughter colonies visible in the parent colony? How many
are visible?
Yes, 22 are visible
107
What is the gas bladder used for within species of Fucus?
Used for flotation devices and allows them to float on the surface regardless of tide.
108
The color of all chloroplasts found within species of Phylum Ochrophyta is __________.
Fill in the blank.
Yellowish to brown
109
Why is it this color (Phylum Ochrophyta)? (the answer involves its chlorophyll pigments)
Fucoxanthin, a pigment, causes them to be brown
110
How do Amoebas and Arcella move? Do they have flagella? Do they have any outer
protection, if yes, what is it called? Which of them have reticulopodia and hat is the
definition of this anatomical part?
They move with pseudopods. They do not have flagella. Only arcella have outer protection and it is called the test. Only Arcella have reticulopodia and it is defined as pseudopodia covered by test that will harden and form connected chambers
111
What are a Foram’s reticulopodia? Filopodia? What are the possible different chemical
components of the tests?
They are the same as arcella’s reticulopodia, pseudopodia covered by test that will harden and form connected chambers. Filopodia are hard spines of ectoplasm. The possible different chemical components are siliceous, calcareous, organic, and pores.
112
What is a radiolarians axopod?
It is a cytoplasmic extension supported by microtubules called axenome.
113
What disease is caused by the protist Trypanosoma? What is a kinoplast?
African sleeping sickness. A kinoplast is when mitochondria that has a minicircle and maxicircle for their DNA
114
How can Spirostomum, Vorticella, and Stentor use their cilia? What is a cytostome?
What is a function of their pellicle?
- Spirostomum use cilia for movement and feeding
- Vorticella use cilia for feeding only
- Stentors use cilia for feeding only
- Cytostome is the mouth
- Pellicle is an outer layer made of protein used to protect
115
Stentor coeruleus can grow to what size on average?
2 millimeters
116
What is one reason cells are normally small?
Large cells are too hard to control, as it takes too long to send information from one part to another
117
How do Gromia sphaerica move?
They crawl by extending tiny feet-like projections called pseudopods through holes in their tests. They leave behind noticeable tracks in the sediment
118
vSpicalosiphon oceana where found near hydrothermal vents and were thought to
originally be a sponge and not a protist. Why did scientists initially think this was the
Case?
The several centimeter long creatures each had a stalk that penetrates into the sediment and holds it in place, and a globe-like top with lots of thin spines sticking out of it - much like carnivorous sponges. These spikes look a lot like spicules, the small, hard structures, made by sponges.
119
Which group do the Spicalosiphon oceana actually belong to instead?
Forams, a group of single-celled amoeba-like organisms.
120
How does Spicalosiphon oceana have spicules if they do not create them on their own?
Why do they do this?
They collect and arrange spicules from carnivorous sponges to steal their look. They do this because it allows them to capture prey, like small invertebrates, in the same way carnivorous sponges do.
121
What are the Spicalosiphon a “canary in a coalmine” for and why?
Just like a canary in a coal mine alerts coal miners for dangers, the spiculosiphon alert scientists of ocean acidification because although they are found being close to hydrothermal vent systems because of the acidity and minerals in those waters, they can’t tolerate super acidic conditions because their shells will dissolve. If scientists see this, this can be a sign for ocean acidification
122
What does Valonia ventricosa look like? How large can they get?
It looks like what one would think a regular cell looks like, except they are supersized. They can grow to be 4 centimeters or larger.
123
Why are Valonia ventricosa similar to grape anatomically speaking?
Their outer cell or cell wall contains a lot of cellulose, just like grape skin
124
Mermaid’s wine glasses or Acetabularia can grow up to be ______________ tall and they kind of look like fungi that you might find carpeting the forest floor with their stems and rounded caps.
10 centimeters
125
Acetabularia has one giant ________ located at the base of its stem. Fill in the blanks.
Nucleus
126
We have covered thus before in class, but what research was completed on Acetabularia
during the 1930s and 1940s
Joachim Hammerling performed a series of experiments on Acetabularia to prove that the nucleus was the control center of the cell. He cut multiple specimens in half and found that only the ones containing the nucleus could regenerate. He also grafted together 2 species of acetabularia and should not be combined all would take on characteristics of whichever species its nucleus came from
127
When does a mermaid’s wine glass have multiple nuclei instead of only one at the base?
When its about to reproduce because its nucleus goes through several divisions to have little nuclei at the base
128
Caulerpa algae are individual cells are some species can grow to carpet a _______ (area) or more?
Square
129
Each Caulerpa algae consists of a _____, _______ that look
like leaves, and the ________ parts that anchor in place. Fill in the blanks.
stem, fronds, and root-like
130
Why can Caulerpa algae grow so large (the video gives two reasonings)?
- It has loads of nuclei to help all parts of it functioning properly
- It uses a process called cytoplasmic streaming that acts like a circulatory system by always keeping the cytoplasm moving in an organized fashion, allowing them to quickly transfer molecules and other structures around the cell.
131
Why is it theorized all plants should be considered unicellular (and not multicellular)?
Their cells are interconnected and communicate with each other through channels called plasmodesmata.
132
Why is life in water less stress for a cell of any size?
In the water, cells won’t dry out, can easily diffuse nutrients and waste products in and out, and fluid pressure gives extra support to their walls
133
Other than malaria, what are three other diseases mentioned in the video that mosquitos
are hosts for?
Dengue fever, zika, yellow fever
134
How many people in 2015 alone were infected with malaria? How many died in 2015
Alone?
200,000,000 were infected, 500,000 people died
135
Malaria always starts with what? Where do the infected protists head once inside a
human? How do they hide from your immune system?
Malaria starts with an insect bite. The protists head to the liver. Once in the liver, they enter big cells and hide from the immune system
136
What type of cells do the Plasmodium infect and destroy once they leave the liver?
Red blood cells
137
What are the symptoms of malaria? What happens if it breaks the blood-brain barrier?
Flu-like Symptoms: high fever, sweats, chills, convulsions, headaches, and sometimes vomiting and diarrhea. If it breaks the barriers it can cause a coma, neurological damage, or death
138
How have scientists used CRISPR to try and get rid of malaria (and other mosquito born
diseases)?
Using CRIPS for genetic engineering, scientists created a strain of mosquitoes that are immune to the malaria parasite by adding a new antibody gene that specifically targets plasmodium. These mosquitos will never spread malaria. This can be done to other mosquito borne diseases as well.
139
Why will creating GMO mosquitos not be the “cure-all” for diseases?
The edits would only be inherited by half the offspring so after two generations only half of the offspring would carry the gene. In a population of billions, this would hardly make a difference
140
How can a gene drive be able to solve the problem of the previous question? What
percent of generations wild type x GMO mosquito will be malaria-resistant now?
A gene drive forces the new gene to become dominant in the following generatoins, overpowering the old gene almost completely. Because of this, 99.5% of all GMO mosquito offspring will carry the anti-malaria edit. If we release enough of these mosquitoes, the gene will spread quickly enough that plasmodium is unable to adapt.
141
So, if using gene drives and GMO-mosquitos can save millions of lives every year, why
have we not used this technology to a high degree? There are two main reasons.
Using CRISPR editing is barely 4 years old so until recently we wouldn’t do it very fast or easily
Humans have never consciously changed the genetic code of a free-living organism on such a large mass. It has to be done right because there could be unwanted consequences from which there is no going back.
142
What is a columella?
The box where the sporangiophore (stalk) forms
143
Which Genus of fungi did you observe that does not complete sexual reproduction?
Penicillium
144
What is a pileus?
Another name for the cap of a fungus
145
What is a hymenium?
Another name for the gills of a funfus. This is where sexual reproduction takes place
146
What exactly are lichen?
Mixture of fungi and bacteria or fungi and algae. Specifically, lichen needs to be fungi + algae/bacteria. The bacteria is usually cyanobacteria which are photosynthetic
147
What is a thallus? What is a cortex? What is a medulla? Where is the algal layer of lichen located?
- Leaf like portion or vegetative body of the lichen.
- The upper layer of thallus
- Loose inner layer of thallus
- It is located right under the upper cortex
148
What is the difference between foliose, fruticose, and crustose lichen?
- Foliose is the leaf-like lichen
- Fruticose has branching thalli and is stem shaped
- Crustose is a crusty type of lichen
149
Scientists believe there are how many species of fungi on earth today?
1.5 mil
150
Why is fungi important to all life cycles on earth?
They are important because they feast on the deceased remains of almost all organisms on the planet, converting the organic matter back into soil, allowing new life to be made.
151
What discovery did Louis Pasteur make in 1857 after studying yeast under a microscope?
He discovered that yeast were living organisms. Through his experiment, he found that in the absence of free oxygen, yeast were able to obtain energy by decomposing substances that contained oxygen (anaerobic respiration)
152
Louis Pasteur also created a process of pasteurization for certain liquids. What is Pasteurization?
A heating process used in mild, canned foods, syrups, wines, and more, in which the product is kept between 55-60 degrees F for a short period of time.
153
What does it mean that fungi are heterotrophs?
They absorb nutrition from their surroundings by secreting powerful enzymes that break down complex molecules into smaller organic compounds, which they use to grow, feed, and reproduce.
154
What are hyphae?
Tiny, tubular filaments that grow through and within whatever the’re feasting on
155
How are the cell walls of fungi reinforced?
Nitrogenous carbohydrate chitin
156
What is a mycelium? What is the purpose of mycelium?
It is the interwoven mass of hyphae that grows into the food source, structured to maximize its surface area. The purpose is to maximize the hyphae in an area, allowing them to secret their enzymes and use food
157
What are the different ways fungi are classified?
One way of classifying them is how they react with other organisms. There are decomposers, those that secret enzymes that break down and absorb nutrients from nonliving organic material. Mutualist fungi have specialized fungi called historia that tangle themselves with plant roots for the benefit of both organisms and their relations are known as mycorrhizae. Predatory fungi capture their prey using their hyphae and parasite fungi feed on living organisms without killing them
158
Fungi can reproduce asexually (no gametes), sexually (gametes), or both ways. But either way, what is the main thing they are trying to accomplish (i.e. what do they produce after replicating)?
Production of spores
159
What is plasmogamy?
A stage in fungi reproduction during which mycelium fuse the cytoplasm of their cells, taking up to hours or centuries-long
