Answer:
Bacteriophages (phages) are viruses that infect only bacteria and do not infect mammalian or plant cells. Phages are ubiquitous in the environment. Phages or bacteriophages were chosen as a model system for their simplicity, as they only contained protein-coated nucleic acid. Alfred D. Hershey and Martha Chase (who were part of the bacteriophage group) in 1952 studying the infection of the bacterium Escherichia coli by the T2 phage show that the information definitely resides in the DNA. They used phage with either [32P] -labeled DNA or [35S] -labeled proteins to infect the bacteria. Immediately afterwards, they centrifuged the sample so that the infected bacteria remain in the pellet and the virus capsids (proteins) remain in the supernatant. [35S] is found in the supernatant, whereas [32P] is found in bacteria. After one cycle of infection, it was observed that when phage labeled in the [35S] proteins were used, only 1% of the radioactivity was incorporated into the progeny. But when phages were [32P] labeled, more than 30% of the radioactivity was in the progeny. They showed directly that what is transmitted from one progeny to another is the DNA and not the proteins, despite having first "diluted" in a bacterium.
Explanation:
Bacteriophages are viruses that infect bacteria in a specific way. Bacteriophages, like other known viruses, are found in an intermediate zone between living organisms and inert matter. Bacteriophages bind to the host pathogenic bacterium, introduce their genetic material, replicate inside it and destroy it. Hersey, along with his assistant Martha Chase, used phages because they knew that T2 phages were made up of 50% proteins and 50% nucleic acids and that phages entered bacteria and reproduced. As the progeny carried the same infection traits, the genetic material of this had to be transmitted to the offspring, but the mechanism was unknown. These scientists carried out an experimental work with the T2 virus, a bacteriophage that infects the bacterium Escherichia coli, which it reproduces by attaching itself to the outer wall of the bacterium, injecting its DNA into it where it replicates and directs the synthesis of the phage's own proteins. Phage DNA is encapsulated within proteins and produces phages, which lyse or disrupt the cell and release phage from progeny. They infected a culture of bacteria with radioactively labeled phages: the protein coat with sulfur (35S) and its DNA with phosphorus (32P). After infection, they separated the phages from the bacteria by violent shaking using a mixer (hence the name of the experiment). By centrifugation the much smaller phages remained in the supernatant and the much larger bacteria in the pellet. 85% of the radioactivity corresponding to DNA appeared in the pellet and 82% of the protein in the supernatant. This result supported the idea that DNA was the only component of the bacteriophage that penetrated the interior of the bacteria and, having the ability to form new phages, constituted the genetic material.
what is environment?
Answer:
the surroundings or conditions in which a person, animal, or plant lives or operates.
Explanation:
Answer:
An enviroment is an ecosytem made up of all living things.
When an enzyme was added that destroyed carbohydrates from the heat-
killed S strain and added to the live R strain, did transformation occur? (Did
transformation happen without the carbohydrates?)
Yes or No
PLS HELP
On the image, which letter represents the enzyme?
Answer:The correct answer is B
Explanation:
I hope this helps you out!
From the image, the letter that represents the enzyme is B.
Enzymes are substances, made up of proteins, which are capable of speeding up the metabolic reactions in the human body.
There is a theory that explains the mechanism of action of enzymes. This is called the enzyme lock and key theory.
This theory states that enzymes bind to substrates temporarily forming enzyme-substrate complex that appears like the fitting of a lock and key.
This simply means that the same way a particular key can only fit into a particular lock is the same way a particular substrate must combine with a particular enzyme for a reaction to occur.
From the diagram,
B represents the enzyme with an active site which must fit into a substrate
A represents the substrate.
Therefore, the the letter that represents the enzyme is B.
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Which step is meiosis is shown in the image below ?
Anaphase I of meiosis in shown in this image.
What do you mean by meiosis?Meiosis is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, such as sperm or egg cells.
Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information. These cells are our sex cells – sperm in males, eggs in females.
Cells divide and reproduce in two ways, mitosis and meiosis. Mitosis results in two identical daughter cells, whereas meiosis results in four sex cells. Like mitosis, meiosis also has distinct stages called prophase, metaphase, anaphase, and telophase.
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Molten lava come to the surface and cool forming the first land. true or false
Answer:
true
Explanation:
common sense
your welcome for helping :)
justify that fluorine cannot exist monoatomic from nature
Answer:
Due to incomplete outermost shell.
Explanation:
Fluorine cannot exist monoatomic in nature because of its incomplete outermost shell. This incomplete outermost shell makes Fluorine more reactive and it can only be stable if it makes bond with other atoms through sharing of electron i. e. covalent bond or by complete transfer of electron i. e. ionic bond. This bond making completes its outermost shell and the Fluorine attain stability so that's why the Fluorine cannot exists in monoatomic in nature.
WHAT ARE SOME DEFENSE MECHANISMS SPECIES USE TO WARD OFF OTHER SPECIES?
Types of animal defense mechanisms
Contents
2.1 Startling the predator.
2.2 Pursuit-deterrent signals.
2.3 Playing dead.
2.4 Distraction.
2.5 Mimicry and aposematism.
2.6 Defensive structures.
plz help me u have to match the word with the defineition BRAINLIESTTTTTTTT and u must do all of them or u will get reported
Answer:
i am so sorry
good luck
Explanation:
Flowes come in red, blue and purple colors. Cross 2 purple flowers what percent of the offspring will be blue
tornadoes occur because a ___ air collides with ___ air. Please help!!
Flowers without petals are called_____
a-complete flowers.
b-eudicot flowers.
c-incomplete flowers.
d-monocot flowers.
Answer:
Letter A.
hope it help ❤️
what best describes transformation in bacteria
Answer:
Bacterial transformation is the transfer of free DNA released from a donor bacterium into the extracellular environment that results in assimilation and usually an expression of the newly acquired trait in a recipient bacterium
Explanation:
Answer:
Bacteria take DNA from their environment.
Explanation:
Bacterial transformation is a process of horizontal gene transfer by which some bacteria take up foreign genetic material (naked DNA) from the environment. ... The prerequisite for bacteria to undergo transformation is its ability to take up free, extracellular genetic material. Such bacteria are termed as competent cells
9. If the concentration of water inside a cell is lower then outside the cell, what will be the net
movement of water molecules be? *
(1 Point)
a) Into the cell.
b) Out of the cell.
Answer:
a) Into the cell.
Explanation:
The water molecules outside the cell would move into the cell until there is no net movement of water molecules. This process is known as osmosis.
Osmosis is the movement of molecules from a region of higher concentration to a region of lower concentration through a semi-permeable membrane until the concentrations across the membrane are equal. That is, there is no net movement of molecules across the membrane.
For a long time scientists have studied the cells of complex organisms. Scientists have discovered that
Answer:
Qweers
Explanation:
Fggs
Scientists have discovered the function of the cell of complex organisms according to their structure.
What is a living cell?The fundamental building blocks of form and operation in living things are cells. This implies that cells make up an organism's components and carry out all of its operations and functions.
The cell membrane, the nucleus, and the cytoplasm are the three primary components of a cell.
They provide the body structure, absorb nutrients from meals, turn those nutrients into energy, and perform certain tasks.
Therefore after a long studied scientist discovered the function of the cell, which perform to do many processes inside the cell of complex organisms.
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why breeding sows and boars should come from good mothers. (pls no long explaining)
Hillsdale and Cordera are the same distance from the equator, and both are near the ocean. Is Cordera warmer, colder, or the same temperature as Hillsdale? Explain why as completely as you can.
Answer:
it is expected that Hillsdale and Cordera have nearly similar temperatures.
Explanation:
In the first place, it is important to note that there is an inverse relationship between latitude and temperature: temperatures are typically warmer near the Equator (lower latitudes) and cooler near the poles (higher latitudes). This phenomenon is due to the fact that the angle of solar radiation is smaller at higher latitudes, and thereby less solar radiation is received/absorbed near the poles than at the Equator. Moreover, another important factor that also determines the temperature is altitude: at higher altitudes, the temperature is lower. This phenomenon is due to the fact that at higher altitude air molecules spread out further, and therefore the temperature decreases. In consequence, at the sea level, the temperature is higher than at higher altitudes.
Which of the following factors is most likely to contribute to gene flow between the
two geese populations?
Answer:
D.migration
Explanation:
The factor that should be contributing to gene flow between the two geese populations is migration.
What is migration?It is the movement that should be moved to another place. It can be the large people, or animals.
So based on this, we can conclude that the factor that should be contribute to gene flow between the two geese populations is migration.
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What is the difference in the function of the glycoprotein structures of an HIV virion and the cilia of an animal cell?
The function of the glycoprotein structures of an HIV virion is the envelope glycoprotein (Env) performs two functions that are very crucial for replication cycle of HIV and these are
binding to a receptor and a coreceptor by using one of its two noncovalently associated subunitsfusing with the plasma cell membranes,which is mediated by the otherThe functions of the cilia of an animal cell are
to move water relative to the cell in a regular movement of the cilialocomotion is the other important function of ciliaWhat is the main difference between function of cilia and glycoprotein structures of an HIV virion?The main function of the cilia is locomotion and sensory function and the main functions of glycoprotein structure of an HIV virion is binding to a receptor and fusing with the plasma cell membranes.
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why do dna strands copy different
Answer:
Because the two strands of a DNA molecule have complementary base pairs, the nucleotide sequence of each strand automatically supplies the information needed to produce its partner.
Explanation:
When mammals get an infection, their internal body temperature often rises 2 to 3 degrees Celsius. The body gets the energy it needs to react to an infection by -
Answer:
The correct answer is - increasing the rate of cellular respiration in the mitochondria.
Explanation:
During the infection, the body of mammals increases its temperature to kill the pathogens that normally die at high temperatures. To increase the body temperature our body promotes the rate of cellular respiration in the cells to produce more energy.
Cellular respiration is the process that helps in converting stored energy into a form of useable energy for the cell which is ATP. It takes place in the mitochondria of the cell which is called as the powerhouse of the cell and all the function related to energy or ATP is conducted by here.
(50 Points)
Select the correct location on the image.
In pea plants, white seed coat is a recessive trait and gray seed coat is a dominant trait. Which offspring have a white seed coat?
The highlighted ones are the answers to chose from (There is only one)
Answer:
gg
Explanation:
Not 50 pts but... recessive usually means it's the tiny letters.
Dominant traits have capital letter GG or Gg, so the dominant trait is going to show as the phenotype.
HELP ASAP ILL MARK BRAINLIEST
Which choice gives the order of a chain of events that show cause and effect relationships that results from human activity?
A. increased carbon dioxide in the atmosphere; increased water vapor in the atmosphere; increase in severe storms; increase flooding
B. increased water vapor in the atmosphere; increase in severe storms; increased carbon dioxide in the atmosphere; increase flooding
C. increased water vapor in the atmosphere; increased carbon dioxide in the atmosphere; increase in severe storms; increase flooding
D. increased carbon dioxide in the atmosphere; increase flooding; increased water vapor in the atmosphere; increase in severe storms
Answer:
D
Explanation
carbon dioxide is enhanced by human activity as it icrease it leads to many consequences so B and C are canceled
increasing carbon dioxide does not increase the water vapor immediatly
so A is canceled
so the left answer will be D
The choice that provides the ordering of the chain of events should be option D where the carbon dioxide should be increased.
What is carbon dioxide?It should be treated as colorless and nonflammable gas at the normal temperature and the pressure. Also it comprise of one carbon atom and 2 oxygen atoms. Here it should be enhanced by the human activity due to which the flooding should be increased, water vapor is also increased also the storms too.
Therefore, the option d is correct.
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When water is cooled, it becomes more dense and sinks to the bottom of the water column. The displaced water is them replaced with ___________.
more cold water from the North and south pole
warm water moving in from the equator
water that is roughly the same temperature as the displaced water
water from volcanic vents
B) warm water moving in from the equator
What are several ways that humans alter the natural habitat?
Answer:
cuting trees, killing animals, and pollution.
Answer:
"Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water."
Explanation:
sources: nationalgeographic
Which is NOT an influencing factor for weather?
Precipitation
Temperature
Gravity
Natural features - oceans, land, mountains, etc.
The answer is to the question is gravity
Cancer is caused by out of control
Answer:
what do you mean by that?
Explanation:
Answer:
Cancer is caused by mutated, or out of control, cells
Explanation:
Give an example or describe how WATER QUALITY can be impacted by the Water Cycle in an Aquatic Environment
Answer:
the water cycle can cause some waters that come from a polluted source to be cycled into aquatic enviroment lowering life quality for the inhabitants. at least i think so
Explanation:
This picture shows examples of a cross section of human skin.
The integumentary system could best be compared to-
Answer:
i don"t know sorry
Explanation:
ask some one
1. Many plants get energy from sunlight. 2. heterotroph get energy by eating other organisms.
3. Water that flows over the surface of the ground is called Surface
4. assimilation is the process by which bacteria turn nitrogen gas int
5. Dead organisms that were buried may turn into oil after millions o
6. Carbon from this material reenters the atmosphere by.
7. Explain: If energy and matter cannot be destroyed, what happens organism is eaten? Goes to other organisms that eat the organism 8. What is the law of conservation of energy? I
9. What is the law of conservation mass?
10. What is at the top of a energy pyramid?
11. A locust would be a consumer.
12. Nitrogen flows from producers through levels of consumers
13. How does water from the atmosphere return to Earth's surface?
14. What would happen to the ecosystem if there were no nitrogen-fixin bacteria?
Answer: All organisms need energy. ...
Autotrophs (producers) use energy directly from the sun or from chemicals to produce organic molecules. ...
Heterotrophs (consumers) obtain energy by consuming other organisms. ...
The flow of energy in an ecosystem can be represented with a food chain or food web
Explanation: A heterotroph is an organism that eats other plants or animals for energy and nutrients. The term stems from the Greek words hetero for “other” and trophe for “nourishment.” Organisms are characterized into two broad categories based upon how they obtain their energy and nutrients: autotrophs and heterotrophs. A consumer is an organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources. Consumers are also called heterotrophs, or other-feeders Producers
Producers: Producers are organisms that get their energy directly from the Sun. Their cells are able to turn sunlight into food through a process called photosynthesis. Organisms, such as humans, take in "substrates" such as glucose, in our food. During a process called respiration, we react 4these substrates with oxygen to give carbon dioxide and water; this takes place in the mitochondria of our cells.
If a diploid cell has 20 chromosomes, how many chromosomes will be in its haploid cell? If a germ cell has 10 chromosomes, how many chromosomes will be in its somatic cells? If a cell in G1 phase has 4 chromosomes, how many chromosomes will it have by the end of meiosis? If an unknown cell is going through mitosis, is it a germ cell or a somatic cell? By the time an unknown cell finishes meiosis, is it a haploid or somatic cell?
Answer:
20
Explanation:
I'm randomly guessed