The following characteristic is functionally important in cells of gametophytes of angiosperms and gymnosperms : b)mitochondria
What is meant by gametophyte?Gametophyte is one of the two alternative multicellular stages in the life cycles of plants and algae. Angiosperms and gymnosperms generate haploid gametophytes or organisms with only one set of chromosomes.
The gametophyte is the sexual phase in the alternation of generations of plants and algae. This stage produces gametes that undergo alternation of generations and it is a haploid phase producing zygote from which sporophytes arise.
Examples of Gametophytes are the fern on a forest floor is a gametophyte
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which of the following is a 'zeitgeber', or an important external stimulus affecting biological clocks?
The information about light that the SCN receives from the retina via the RHT serves as the most significant signal (or "zeitgeber" in scientific parlance) in synchronising the biological clock.
The zeitgebers include things like light, temperature, eating and drinking habits, etc. These environmental cues support the biological clock's ability to maintain rhythmic cycle consistency. The most significant Zeitgeber is light. Zeitgeber time (ZT) is a standardised 24-hour notation for the phase in an entrained circadian cycle, with ZT 0 denoting the start of daytime or the light phase and ZT 12 denoting the start of nighttime or the dark phase. See circadian time for a comparison.
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Please select all of the possible applications of DNA fingerprinting to test your understanding of several applications of DNA fingerprinting.Check All That Apply-forensics-detection of genetic disease-identifying microorganisms-determining parentage-replacing defective genes
Forensics, genetic disease detection, microorganism identification, and parentage determination.
Why is DNA fingerprinting important?DNA fingerprinting was first used to solve homicides and prove paternity in court cases. It may be used to identify inherited genetic diseases and determine if tissue donors and recipients share the same genetic traits. A big, flat basic molecule that mimics a pair of DNA bases is called ethidium bromide (EtBr). In molecular biology laboratories, ethidium bromide is frequently used to stain electrophoresis gels.
How does PCR fit into DNA fingerprinting?Primers that target several of these repeated components are used in the repetitive sequence-based PCR, or rep-PCR, DNA fingerprint technique to produce distinctive DNA profiles, or "fingerprints," of certain microbial strains.
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The complete question is -
Please select all of the possible applications of DNA fingerprinting to test your understanding of several applications of DNA fingerprinting.
Check All That Apply
-forensics
-detection of genetic disease
-identifying microorganisms
-determining parentage
-replacing defective genes
Which one of the following is a trait that increases the chances of survival for an endangered species?
A: large size
B: long life span
C: widespread distribution
D: small number of offspring
Option C is correct : widespread distribution is a trait that increases the chances of survival for an endangered species
An endangered species with a widespread distribution has a greater chance of survival than a species that is confined to a small, isolated area. A widespread distribution allows a species to occupy multiple habitats, increasing their chances of finding food, water, and other resources needed for survival. It also reduces the risk of natural disasters or human activities affecting the entire population at once.
While a large size or a long life span may provide some advantages for an individual, they do not necessarily increase the chances of survival for an entire endangered species. In fact, a species with a small size or a short life span may have a higher reproductive rate and adaptability, allowing them to recover more quickly from population declines.
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fill in the blank. in order to transform the___of atp into ___ to do work, the bonds of atp must be broken into adp and an available phosphate group.
In order to transform the energy of ATP into work, the bonds of ATP must be broken into ADP and an available phosphate group.
ATP is a nucleotide that contains a ribose sugar molecule, a nitrogen-containing adenine molecule, and three phosphate groups that are negatively charged.
ATP, or adenosine triphosphate, is a high-energy molecule that serves as the primary energy source for cellular functions. It acts as the power source for all biological activities in cells by supplying energy.
It is produced during cellular respiration, a process that converts glucose and oxygen into energy in the form of ATP. The energy stored in the high-energy bonds of ATP can be utilized to carry out a variety of cellular functions, such as transporting molecules across cell membranes, synthesizing complex molecules, and moving cells.
When ATP is used to accomplish work, it is converted to ADP (adenosine diphosphate) and an available phosphate group, and the energy stored in its bonds is released to do work. This process is referred to as hydrolysis.
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Which statement would be MOST important to include in a summary of the article?
A
Models are used to represent objects and events in the real world.
B
Maps can be created on paper as well as digitally in people's phones.
C
Scales on maps use measurements in miles or kilometers.
D
Microscopes use lenses that bend light to make objects appear larger.
Answer:
D.) Microscopes use lenses that bend light to make objects appear larger.
Explanation:
I believe this is correct because it gives more detail in its sentence providing more information on a subject.
The papillae are denser on the bottom of the rumen than on the top. What is the reason for this?
Dense feed sinks to the bottom/ when lighter feed breaks down, the particles absorb water and sink to the bottom-->the papillae greatly increase surface area for absorption of nutrients of the feed. The bottom is where majority of microbe activity/nutrient breakdown occurs.
A blunt force injury to the forehead would result in a contrecoup injury to which region of
the brain?
A. Frontal
B Temporal
c. Parietal
d. Occipital
Spinal cord injuries most likely occur in which region?
A Cervical and thoracic
B Lumbar and sacral
C Thoracic and lumbar
d. Cervical and thoracic-lumbar
Answer:
Frontal lobe/ forehead
Cervical and thoracic
Explanation: A “coup” injury occurs directly under the site where the head receives the blunt force trauma. Most often, in car accidents, this occurs at the frontal lobe (forehead) or the temples.
spinal cord injuries are most common in the cervical region (the upper-most region of the spine, starting just below the skull) and the thoracic region (the middle of the spine, between the cervical and lumbar regions)
What does receiver bee stand over???
Answer:
The flower.
Explanation:
It eats the nectar and the pollen sticks onto its fur, so that it can pollinate other flowers.
True/False: The Heimlich maneuver is a procedure in which air in the lungs is used to expel a piece of food that obstructs the opening to the trachea.
False.The Heimlich maneuver, also known as abdominal thrusts, is a first aid procedure used to dislodge an obstruction from a person's windpipe, or trachea.
What is a trachea ?The trachea, also known as the windpipe, is a tube-like structure that connects the larynx, or voice box, to the bronchi in the lungs. It is located in the neck and chest and is an important part of the respiratory system.
The trachea is composed of a series of C-shaped rings of cartilage that provide structural support and prevent the trachea from collapsing. The walls of the trachea are lined with a mucous membrane that secretes mucus to help trap and remove foreign particles and microbes from the air before they reach the lungs.
The trachea also contains cilia, tiny hair-like structures that beat in coordinated waves to move mucus and trapped particles up and out of the respiratory system. This helps to protect the lungs from infection and other respiratory diseases.
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please help need this soon
Frequency of dominant allele: 0.99
Frequency of recessive allele: 0.01
% homozygous dominant: 98.01%
% homozygous recessive: 0.01%
% heterozygous: 1.98%
What is Hardy -Weinberg equation?The Hardy-Weinberg equation is a mathematical model that describes the relationship between the frequencies of alleles and genotypes in a population. It is based on the assumptions of a large population size, random mating, no migration, no mutation, and no natural selection.
The equation is:
p² + 2pq + q² = 1
where:
p = frequency of the dominant allele
q = frequency of the recessive allele
p² = frequency of the homozygous dominant genotype
q² = frequency of the homozygous recessive genotype
2pq = frequency of the heterozygous genotype.
Given that cystic fibrosis is a homozygous recessive condition that affects 1 in 10,000 of the Hispanic population in the US, we can assume that the frequency of the recessive allele is q = √(1/10000) = 0.01.
To calculate the frequency of the dominant allele, we can use p = 1 - q = 1 - 0.01 = 0.99.
Now we can use the Hardy-Weinberg equation to calculate the frequencies of the different genotypes:
p² = (0.99)² = 0.9801 = 98.01% homozygous dominant
2pq = 2(0.99)(0.01) = 0.0198 = 1.98% heterozygous
q² = (0.01)² = 0.0001 = 0.01% homozygous recessive
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Skeletal muscles usually consist of several distinct types of muscle fibers. Different muscle fiber types in the same muscle become apparent when certain dyes are applied, as seen in the stained micrograph on the right. Consider the three muscle fiber types labeled Type A Type B, and Type C. -Type C Type B Type A Dr. Gladden Willis / Visuals Unlimited, Inc./Getty Images Each muscle ber type has a unique set of contractile properties. The following graphs plot the force of muscle fiber contractions in response to a single stimulus (a single action potential, shown as one black arrowhead), a short burst of stimull (a rapid succession of action potentials, shown as a sequence of black arrowheads), and repeated bursts of stimull (a sustained succession of action potentials, shown as a continuous black bar). Force produced due to a single stimulus Force produced due to a short burst of stimuli Force produced due to repeated bursts of stimuli 0.5 0.5- Force produced due to a single stimulus Force produced due to a short burst of stimuli Force produced due to repeated bursts of stimuli 0.5- 0.5- 0.4 0.4 0.3 0.3- Force (N) 0.2- 0.2- 0.1 0.1- 0 0- 0 50 100 150 200 250 300 Time (msec) 0 0 2 60 500 1000 1500 Time (msec) 4 6 Time (min) In each row of the following table, identify the muscle fiber type or types described by each statement. Check all that apply. Type A Type В Type с When these muscle fibers experience a short burst of stimuli, fatigue sets in within 750 milliseconds of the first stimulus. s This muscle fiber type can still generate force after 60 minutes of repeated stimulation. This muscle fiber type produces the strongest possible peak force. In other words, it has the strongest contractile activity Based on how these three muscle fiber types respond to different stimull, Type B y fibers are most likely to be abundant in muscles that contract very strongly but only for a short period of time. These fibers are also known as fast aerobic muscle fibers.
Skeletal muscle fibres come in two varieties: type I slow-twitch and type II fast-twitch (type II). Fast-twitch muscle fibres assist short, strong actions like sprinting or weightlifting.
While slow-twitch muscle fibres support long distance endurance sports like marathon running. The majority of skeletal muscles in humans contain a mix of fibre types: postural and endurance muscles have a higher proportion of MHC I fibres, whereas muscles involved in quick, powerful, short-duration movements have a higher proportion of MHC IIA and IIX fibres. More mitochondria are present in type 1 ("slow twitch") fibres, which enables them to create more energy and makes them ideal for prolonged, aerobic activity.
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What are two different types of muscle fibres that can be found in skeletal muscles name some characteristics?
In what type of organisms can the CRISPR/Cas system be found naturally?
which of the following favors filtration into the bowman's or glomerular capsule of nephron? multiple select question.
in the atmosphere are several distinct global wind patterns. where there are low pressure belts, the air is ___
In the atmosphere, there are several distinct global wind patterns. When there are low-pressure belts, the air is rising.
Air in low-pressure belts rises since the atmospheric pressure is much lower than the atmospheric pressure around it. When the air gets warmed up, it rises, and it reduces the pressure in the surrounding air. In the tropics, the intertropical convergence zone, or ITCZ is a zone of low-pressure belts where the trade winds converge. At the equator, it rises, cools down, and goes towards the poles. It is the area that receives the most rainfall on earth since the warm air has more moisture content that condenses as it rises and cools down. This belt is very important for the earth's climate since it is responsible for regulating weather patterns across the planet. Winds move from high pressure to low pressure, and that creates air currents. Warm air rises, and cool air sinks, and that creates convection cells. These convection cells create high and low-pressure belts around the earth, and it creates the weather patterns that we see daily.
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t/f a condition that occurs when warm air traps cooler air at the surface of the earth is greenhouse gases.
False. A condition that occurs when warm air traps cooler air at the surface of the earth is greenhouse gases called an inversion.
When a layer of warm air forms above a layer of cooler air, pollutants and other particles near to the earth are effectively trapped. This can result in the buildup of smog, particulate matter, and other harmful substances, all of which can damage human health and the environment.
These gases, which include carbon dioxide, methane, and water vapor, trap heat in the atmosphere and add to global warming. The greenhouse effect is a natural process that is required for life to exist on Earth.
However, human actions such as the use of fossil fuels and deforestation have increased greenhouse gas emissions, causing global temperatures to rise and resulting in climate change.
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Complete question
A condition that occurs when warm air traps cooler air at the surface of the earth is greenhouse gases is Inversion. True or False
Which of the following can cause erosion?
Group of answer choices
falling leaves
flowing water
rising temperatures
growing grass
Answer:
Explanation:
Rising Temperatures because the humidity will cause erosion as well
The T cell receptor (TCR) on T helper cells most likely recognizes:
A. short peptides inside a non-enzymatic protein.
B. long peptides inside an enzymatic protein.
C. short polysaccharides inside an enzymatic protein.
D. long-chain fatty acids inside a non-enzymatic protein.
Option A. The T cell receptor (TCR) on T helper cells most likely recognizes: short peptides inside a non-enzymatic protein.
What are T cell receptor (TCR)?The T cell receptor (TCR) on T helper cells most likely recognizes short peptides inside a non-enzymatic protein.
T helper cells play a critical role in the adaptive immune response, specifically by recognizing and responding to foreign antigens displayed on the surface of antigen-presenting cells (APCs). The TCR on T helper cells binds to antigenic peptides that are displayed on the major histocompatibility complex (MHC) molecules on the surface of APCs.
In general, the antigenic peptides recognized by TCRs are short peptides (usually 8-20 amino acids in length) that are derived from proteins that have been degraded within the APC. These peptides can come from non-enzymatic proteins or enzymatic proteins, but they are typically not long enough to constitute entire protein sequences.
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name two features of the 16s rrna that made this a good method for determining the secondary structure.
16S rRNA has two characteristics that make it a useful tool for figuring out the secondary structure. They are:
Highly conserved sequences: The 16S rRNA gene is highly conserved among various bacterial species, indicating that some sections of the RNA have not altered over a significant amount of time during evolution. Due to the sequence's conservation, homologous regions can be found and identified, allowing for the prediction of the molecule's secondary structure.
Base-pairing interactions: The secondary structure of 16S rRNA is stabilized by a significant number of base-pairing interactions, in which complementary nucleotides form hydrogen bonds. These interactions provide the RNA molecule a sturdy framework and make it reasonably simple to anticipate the secondary structure using established base-pairing rules.
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What do you think is the relationship between the buoyant force and the weight of displaced liquid?
In light of this, the buoyant force and the liquid's displacement weight are equal.
What is meant by buoyant force?A fluid's buoyant force is the upward push it applies to an item. The buoyant force that is equal to the fluid's displacement weight is known as the Archimedes Principle.Here are a few instances where the buoyant force is present in daily life. A ship cruising the seas, a boat moving down a river, an iceberg floating in the water, a person wearing a life jacket, a balloon rising in the air, etc. The density has an impact on the buoyant force. When an object is fully or partially submerged in a fluid, buoyancy, also known as a buoyant force, is the propensity of the fluid to pull the object higher. A buoyant force is measured in Newtons in the S.I.To learn more about buoyant force, refer to:
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To which side of the kidney does the ureter connect?
A. Proximal
B. Superior
C. Medial
D. Axial
The ureter connects to the C.) medial side of each kidney.
What is the function of kidney?Kidneys' primary function is to remove toxins from the blood and convert waste products into urine. The average kidney weighs 160 grammes and excretes 1.5 litres of urine every day. Every 24 hours, two kidneys work together to filter 200 litres of fluid.
The kidneys aid to maintain the body's chemical balance by excreting waste and excess water from the blood as urine and removing excess salt, potassium, and calcium. Additionally, they produce hormones that encourage bone marrow to produce red blood cells, which is referred to as renal function. They also assist manage blood pressure.
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Snails are the final host in the life cycle of blood flukes.
Please select the best answer from the choices provided
T
F
Answer:
trueee. . . .. ..................
What was the independent variable in the first catalase experiment?
Answer:
Independent and Dependent Variables Independent Variable: The independent variable is the chicken liver and the potato. Dependent Variable: The dependent variable is what I will be measuring which is how much peroxide I will use for each individual experiment.
PLEASE HELP! Thank you! Website doesn’t work
The Bacteria and what their features represent include bacillus ( rod shaped ), coccus ( spherical), spirillum ( spiral ), diplo ( pairs ), strepto (chains), and staphylo (clusters).
What are some types of bacteria ?There are various types of bacteria that occur in nature and some of them include:
bacillus - Rod-shaped bacteriacoccus - Spherical-shaped bacteriaspirillum - Spiral-shaped bacteriadiplo - Bacteria that occur in pairsstrepto - Bacteria that occur in chainsstaphylo - Bacteria that occur in clusters or groupsHow do Bacillus occur in nature?The bacteria in the diagram include:
Diagram 1: BacillusDiagram 2: DiplococcusDiagram 3: StreptococcusDiagram 4: CoccusDiagram 5: StreptococcusDiagram 6: BacillusDiagram 7: SpirillumDiagram 8: StaphylococcusDiagram 9: BacillusBacillus occurs in nature in various forms, including soil, water, and air. They are commonly found in soil, where they play a vital role in decomposing organic matter. Bacillus also occurs naturally in water, including freshwater and saltwater.
Some Bacillus species are known to survive extreme environmental conditions, including high temperatures, radiation, and desiccation, allowing them to exist in a dormant state for extended periods.
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Image transcribed:
Use the following website: http://biology.clc.uc.edu/courses/bio106/bacteria.htm or your notes to fill in the meaning of the term on the line next to the term.
1. bacillus
2. coccus
3. spirillum
4. diplo
5. strepto
6. staphylo
Use the terms you defined above to name the bacteria in each diagram below. Write the name on the line below each diagram. Note: Some names will combine two of the terms. For instance, a chain (strepto) of round (coccus) bacteria is called streptococcus.
the organelles found in modern eukaryotic cells which are responsible for providing energy for the cell are ___________ and _____________.
The organelles found in modern eukaryotic cells which are responsible for providing energy for the cell are mitochondria and chloroplasts.
Mitochondria are known as the "powerhouse" of the cell as they convert energy from food molecules into a form the cell can use, known as ATP. Chloroplasts are responsible for photosynthesis, which captures the energy from sunlight and converts it into a form the cell can use The organelles found in modern eukaryotic cells which are responsible for providing energy for the cell are mitochondria and chloroplasts.Eukaryotic cells are organisms whose cells have a nucleus and other organelles enclosed by a plasma membrane.
The organelles found in modern eukaryotic cells that are responsible for providing energy for the cell are mitochondria and chloroplasts.The majority of eukaryotes have mitochondria, which are responsible for cellular respiration. Mitochondria are an essential part of cellular respiration, which generates ATP, the molecule that supplies the cell with energy. Chloroplasts, on the other hand, are responsible for photosynthesis in plants and algae.The answer is: Mitochondria and chloroplasts.
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How was the dependent variable in the catalase experiment measured?
The rate of the reaction is the dependent variable. The concentrations of the enzyme, substrate, temperature and the presence of an inhibitor are the independent variables.
What is a catalase experiment?The impact of substrate concentration on reaction rate is investigated in this experiment. In a beaker containing hydrogen peroxide, porous filter paper discs are first dipped in a catalase solution. Oxygen bubbles begin as little ones and grow in size as the process progresses.Students can assess the effects of temperature and pH on the effectiveness of catalase using a typical enzyme lab. The enzyme catalase converts hydrogen peroxide (H2O2) into oxygen and water, and it is present in practically all living things. A common source of catalase used by educators is raw chicken liver or potato. By adding hydrogen peroxide to the bacteria, it is easy to detect whether they make catalase.To learn more about catalase experiment, refer to:
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Please help me solve the first question step by step
A. The concentration of algal cells at 0.08 absorbance would be 2 10E6 if we extrapolate the given graph.
How to check the absorbanceOur standard culture is this. A 0.5 10E6 concentration is what we need. Our stock will be diluted as a result.
we have 0.5 x 10⁶
the original stock is given as 2 x 10⁶
The df = 15 + 5 / 5
= 4
Final volume / initial volume
2 x 10⁶ / 4
= 0.5 x 10⁶
b. The number of microbial cells in a culture of microbes affects how much of it is absorbed.
The absorbance was lower at the beginning of the culture because there were fewer algal cells present. At the end of the culture, when enough algal cells had grown, the concentration of algal cells had also increased, making the absorbance value higher.
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Carbon sinks are reservoirs that hold large amounts of carbon. Which of the following are considered to be carbon sinks? Ο Ο Ο fossil fuels deep underground Ο the atmosphere Ο All of the answer choices are correct
None of the answer choices are correct because Fossil fuels and the atmosphere are not considered to be carbon sinks.
What are carbon sinks?
Carbon sinks are natural or artificial reservoirs that absorb and store atmospheric carbon dioxide (CO2) from the atmosphere through biological or physical processes.
The main natural carbon sinks are oceans, forests, and soil, which take up CO2 through photosynthesis and absorption. Carbon sinks help to mitigate climate change by reducing the amount of greenhouse gases in the atmosphere, which can help to reduce global warming.
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clostridium tetani, the bacterium that causes tetanus, can only survive in soil away from oxygen. it is considered which of the following?
Tetanus-causing bacteria Clostridium tetani is regarded as an obligate anaerobe. It can only exist in surroundings devoid of oxygen, which means that it cannot thrive in the presence of oxygen.
What allows Clostridium tetani to endure?The creature is heat-sensitive and is incapable of surviving in an oxygen-rich environment. In contrast, the spores are remarkably resistant to heat and common antiseptics.
Can the tetanus-causing Clostridium tetani bacterium only endure in oxygen-free soil?The bacteria Clostridium tetani produces a toxin (poison) that causes tetanus. Oxygen prevents the C. tetani bacteria from surviving. Because to their resistance to heat and other chemicals, they develop spores that are particularly challenging to eradicate.
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which of the following indicates the function of sodium bicarbonate released by the pancreas
The pancreas secretes a lot of sodium bicarbonate, which cancels out stomach acid and protects the duodenum. The stomach is a large, bean-shaped, hollow muscular organ with four regions: Persist reading for more info.
The pancreas secretes sodium bicarbonate to aid digestion. Certain enzymes are broken down and stomach acid generated during digestion is neutralized by this compound.
An antacid called sodium bicarbonate is used to treat acid indigestion and heartburn. In some cases, your doctor may also prescribe sodium bicarbonate to make your urine or blood less acidic. Occasionally, this medication is prescribed for other purposes; For more information, consult your physician or pharmacist.
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Select the combinations of strains that would have allowed successful replication of the Lederberg and Tatum experiment. (Check all that apply.) Check All That Apply met biof the leu thi and met biof thr* leu thi* met bio thrleu thi and met bio thrleuthit met bio thr leu thi and met bio thrleut thr met bio thr leu thi and met biof thrt leut thit
The combinations of strains that would have allowed successful replication of the Lederberg and Tatum experiment are:
met bio and leu thimet bio thr* and leu thi*met bio thr leu thi and thrleuthitmet bio thr leu thi and thrleutWhat is the expression of genetic exchange?The Lederberg and Tatum experiment demonstrated that genetic exchange can occur between bacteria through conjugation. In this experiment, two different strains of bacteria were used: one strain was auxotrophic for methionine and biotin (met bio), while the other strain was auxotrophic for leucine and threonine (leu thi).
To allow for genetic exchange to occur, the strains needed to have complementary auxotrophies, such that the recipient strain was able to grow in the presence of the nutrient(s) that the donor strain was unable to synthesize.
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