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.
Using the Periodic Table of Elements, what group of elements are also known as the Halogen Family?
Answer:
I NEED SOME POINTS TO ASK A QUESTION UGH
Explanation:
Answer:
the answer is this hope it helps
The chemical colchicine is used in the production of karyotypes. Colchicine prevents spindle fibers from forming during the cell cycle. What is a result of preventing spindle fibers from forming? Answer
A The cell cycle skips G1 phase
B Mitotic division is skipped, and the cell cycle proceeds to cytokinesis.
C Mitotic division stops in metaphase and cannot proceed to anaphase.
D The cell cycle skips S phase and proceeds to G2 phase.
Answer: the correct answer is C
Explanation:
Preventing the formation of spindle fibers makes the mitotic division stop in metaphase, and thus fail to proceed to anaphase.
• Colchicine prevents the polymerization of the microtubule, and thus, prevents the arrangement of the mitotic spindle, which shows the prevalence of another checkpoint in the cell cycle.
• As a result, the activity of the maturation promoting factor remains high, the chromosomes stay condensed, and the nuclear envelope fails to redevelop.
• A toxic effect is exerted on the living cells by the colchicine, which usually results in the arrest of the process of mitosis at an eventual stage, generally the metaphase, with the generation of unusual and bizarre nuclear configurations, and thus, resulting in the death of the cell.
Thus, the correct answer is option C.
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Why do we not use a Punnett Square to determine the offspring for asexual reproduction? Is that form of reproduction diverse? Explain your answer.
Answer: There isn’t another organism to cross with
Explanation:
In asexual reproduction there is only one parent so all the genes come from one person.
Which two fields of study provide the core information that is used to classify organisms?
how cutting down trees contribute to global warming??
Answer:
Carbon is stored in the plant, which helps a plant to grow. But when trees are cut down and burned and or allowed to rot, their basically storing carbon dioxide, which then gets released into the air ... again known as carbon dioxide. In conclusion this is how deforestation or cutting down trees and including forests can lead to and or contribute to global warming.
List at least five facts about brain health and protection.
Answer:
always use protection but of no one lisens to that saying.
1.)Weave heart-pumping exercise into your daily routine.
2.)Take care of any medical problems.
3.)Get enough sleep, and get help for existing sleep problems.
4.)Review the medications you’re taking with your doctor.
5.)Stay socially engaged.
Match the mechanism to the most likely outcome for each column. One mechanism may be chosen more than once.
PUNTOskkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkkj
I will mark someone brainliest! Please help!!
Answer:
The first one
Explanation:
Mark me brainliest please
. Which statement best expresses the central idea in the article?
A. Scientists have discovered a way to prevent genetic defects in babies, but some believe genetic development should be left to nature
B. Scientists have discovered a way to prevent genetic defects in babies, but some worry that the process could be used for great economic gain
C. Scientists have discovered a way to prevent genetic defects in babies, but the method is against many families’ religions
D. Scientists have discovered a way to prevent genetic defects in babies, but the process is still very risky
Answer:
I believe the Answer is D
Explanation:
Mainly because b, c, arent very logical and A is also a decent choice but i believe d is the answer
Which monomer – polymer pair below is mismatched? *
2 points
amino acid-protein
glucose-glycogen
glucose-starch
amino acids-nucleotide
Answer:
glucose-glycogen
Explanation:
Because extra glucose is converted into glycogen and stored for when it is needed. It is not a polymer pair.
Mom is a dominant purebred for big feet. Dad is a hybrid for foot size. What are their chances of big feet? Or little feet? _ out of _ or _ %
Answer:
Parent´s chances:
Mom´s chances of giving their children the big feet allele are 2 out of 2, or 100%Mom´s chances of giving their children the small feet allele are 0 out of 2, or 0%Dad´s chances of giving their children the big feet allele are 1 out of 2, or 50%.Dad´s chances of giving their children the small feet allele are 1 out of 2, or 50%Offspring chances:
The offspring have 4 out of 4 or 100% of probability of having big feet. And 0 over 4 or 0% of probabilities of having short feet.Explanation:
Due to technical problems, you will find the complete answer and explanation in the attached file
magnetite is________that acts like a magnet
A.a compass
B.an electric circuit
C.a mineral
D.a planet
Answer:
C. a mineral
Explanation:
magnetite is a naturally-occuring mineral found in the lithosphere. Like other metals (such as iron), it has electromagnetic properties.
Which of Earth's layers is the thinnest?
OA.
outer core
ОВ.
crust
OC.
mantle
OD.
inner core
PLEASE HELP! Giving extra points & will mark as Brainliest!
1.Looking at the map of epicenters shown above, what do you notice about the location of most of the worlds earthquakes? What patterns do you notice?
2. Explain the pattern of the earthquake epicenters shown on the map. Why do most of the world’s earthquakes occur in these areas?
Answer:
the answer is jesus... the answer to everything is jesus
Explanation:
he is the son of god and died for our sins
A group of individuals of the same species living together is called a:
Answer:
Population
Explanation:
The greatest amount of genetic variation is produced in offspring that reproduce -
A. sexually through fission B. asexually through budding C. sexually through meiosis D. asexually through mitosis
In meiosis, the greatest amount of genetic variation is produced in offspring that reproduce sexually, hence option C is correct.
How do organisms reproduce sexually through meiosis?Because the environment is continually changing, sexual reproduction often has an advantage over asexual reproduction.
Increased phenotypic variation, or the physical variety of the organisms, results from higher genetic diversity.
Each gamete has a unique DNA set because of recombination and independent assortment during meiosis. The resultant zygote has a special set of genes as a result.
Genetic variety can be increased by new genes and alleles being created as a result of gene duplication, mutation, or other events.
Therefore, it is possible for novel gene combinations to arise during sexual reproduction.
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Why do you think mining on land would be less costly than mining in the ocean?
Explanation:
Because dense minerals are heavier and drop to the stream bottom, lighter minerals are carried along in the current of the stream. Why do you think that mining on land is less costly than mining in the deep ocean is? It is easier to get to land than the ocean and you need special equipment to go under water.
True or False: Our organ systems work separately and do not interact with each other at all in our bodies
What's cycle works together with the carbon cycle
Answer: The carbon cycle is nature's way of reusing carbon atoms, which travel from the atmosphere into organisms in the Earth and then back into the atmosphere over and over again. Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms
Explanation:
Pls help! Explain why blood pressure must decrease in the arterioles before entering the capillaries ahhhhh
this is because the blood flow slow through the capillaries to allow gaseous exchange. Plus the pressure is higher in capillaries because the diameter of the capillaries is smaller than arterioles
what's one thing u wonder about ocean exploration
Name THREE products in the food industry that are produced by biotechnology
BT crops are developed by adding traits from which of the following organisms?
phytoplankton
bacteria
viruses
superweeds
Answer:
bacteria
Explanation:
'Bt' crops are genetically modified crops that contains a certain gene of a bacteria called Bacillus thuringiensis. The name of this GM or transgenic crop was coined from the bacteria used.
The gene coding for the toxic traits of the bacteria are added into Bt crops e.g cotton, hence, the crops become resistant to pest attack. Therefore, according to this question, BT crops are developed by adding traits from BACTERIA.
If today is Monday and it is a 1st quarter moon, what phase will it be on Thursday
Answer:
Saturday
Explanation:
because
When an organism has two alleles at a particular locus that are different, then the organism is called what?
Purebred
Dominant
Heterozygous
Recessive
Answer:
Heterozygous
Explanation:
Which of the following stages of photosynthesis involves carbon fixation, reduction reactions, and the ribulose 1,5-bisphosphate regeneration?
photoreduction
light-independent reaction
light-dependent reaction
first stage photosynthesis
Answer:
light-independent reaction
Explanation:
Photosynthesis, which is a unique metabolic process where plants synthesize their food (glucose) in the presence of sunlight, occurs in two stages namely: light dependent stage and light-independent stage.
The light independent stage is also known as dark stage because it does not require light to occur. It occurs in the stroma of the chloroplast where ATP and NADPH are used to fix carbon into the production of glucose. This stage involves three major processes:
- Carbon fixation of CO2
- Reduction reactions of G3P
- Regeneration of ribulose 1,5-bisphosphate (RUBP).
Scientists hypothesize that early whale ancestors were amphibious. Which statement
below is most consistent with this hypothesis? The fossil animals ____________.
HELP MEEE,!!!!! PLEASE
Answer:
C
Explanation:
spindle fibers are important during metaphase. division stops without them.
Why are DNA fingerprints are more reliable than hand fingerprints in solving crimes.
Answer:
Fingerprints are still the most cost-effective and reliable way to identify people: ... No two fingerprints have ever been identical in the many millions of comparisons. Fingerprints solve ten times more unknown-suspect cases than DNA fingerprinting.
Explanation:
how many codons specify 5 amino acids?
Answer:
20, Im not completely sure tho
Explanation: