Answer:E. Adenine and Guanine
They are double double carbon- nitrogen rings with four nitrogen atoms bases found in DNA and RNA. Purines always pair with pyrimidines(cytosine and thymine) to form a double helix structure.This precise paring ensured that the DNA has a complementary structure.
This paring of purines with pyrimidines is by hydrogen bonds. This is to ensure easily unwinding during replication, that is formation of new DNA molecules.
purines bases are also used for cell protein synthesis fro cell division.
Answer:E. Adenine and Guanine
Explanation:the DNA is a long ,linear chain of subunits called nucleotides.each nucleotides contains a sugar phosphate which is deoxyribose phosphate and also nitrogenous bases.
Nitrogenous bases usually contains carbon, hydrogen, oxygen and nitrogen.
The nitrogenous base are adenine, cytosine, guanine and thymine.
Adenine and guanine are purines.
Cytosine and thymine are pryrimidine.
In RNA , thymine is replaced by uracil
TRUE/FALSEThe telephone book shows relationships and is, therefore, a good example of a natural system of classification.
It just shows your address and phone number
If an individual was exercising at an exercise intensity of 1.5 liters of oxygen per minute, and had a mechanical efficiency of 20 percent, how many heat Calories would this person generate in 30 minutes?
Total calories = 45 calories
intensity of oxygen per minute = 1.5 lt
mechanical efficiency = 20%
time = 30 minutes
1 litre of oxygen = 5 calories per minutes
Total calories = oxygen quantity/min * time* efficiency* cal/min
Total calories = 1.5*30*0.20*5
Total calories = 45 calories
Part A Do you think three weeks (21 days) is enough time to observe all of the Moon’s phases? Why or why not?
No they do not.
The moon occurs every 29.5 days
No, I don't think so.
The reason is, in order to fully track the moon, you would need about 27 days because that is how long it take the moon to complete one full orbit around the Earth. However, if you don't think that you will need 27 days because some of the days there won't be a phase change then, that is up to you. Hope this helps.
What is the term for an atom that is electrically charged as a result of gaining or losing electrons?
An electrically charged atom as a result of gaining or losing electrons is called an ion.
What is an ion?
An ion is an atom that has an unequal number of electrons and protons, resulting in an overall electrical charge. When an atom gains or loses electrons, it becomes charged, and the resulting charged atom is called an ion.
Ions can be either positively charged (when they have lost electrons) or negatively charged (when they have gained electrons). Ions play important roles in many biological and chemical processes, including the transport of ions across cell membranes, which is critical for communication between cells and for the regulation of functions like muscle contractions and heartbeat. Additionally, ions play a role in the formation of ions and bonds, which are essential for the formation of molecules and for the maintenance of structure in many biological and chemical systems.
Learn more about ions, here:
The reason is, an ion is a charged particle. The charge can be either a positive charge or a negative charge.
Na+ : Cation (positively charged ion/particle)
Cl- : Anion (negatively charged ion/particle)
Dietary Supplements and Fortified Foods Dietary supplements are more popular than ever, particularly among older adults. They are used with intentions like boosting an inadequate diet, preventing a chronic disease, or managing a health condition. Fortified foods may also be used to help individuals increase specific nutrients in their diets.
Select all the sentences below that correctly describe dietary supplements.
Select all that apply.
Select all that apply.
1- Large doses of dietary supplements are unlikely to pose any adverse health effects.
2- A multivitamin supplement provides all of the benefits of fruits and vegetables.
3- Dietary supplements can be beneficial for pregnant women, vegetarians and vegans, older adults, those with lactose intolerance, and anyone else who has a difficult time meeting nutrient needs through food.
4-Dietary supplements are approved and strictly regulated by the FDA.
5- Fortified foods can increase the risk of overconsuming certain nutrients.
These supplements are just for complementing the naturaly available food subtances.And in some cases in adults to boost reduced quantities in old people.
However overconsumption of these materials have adverse effects Besides these products(minerals and vitamins can not replace the naturaly available components of fruits and vegetables, because they are synthetic, and the chemical components can affect the body physiological mechanisms especialy of the kidney and liver.Unlike natural components that are easily metabolise by the's ogans.
Identify the FALSE statement. The primary atmosphere: a. consisted mainly of water, carbon dioxide, carbon monoxide, and methane.
b. that escaped from Earth was then blown away by the solar wind.
c. was replaced by a secondary atmosphere consisting mainly of gases melted out of minerals within the Earth and released through volcanoes.
d. was replaced by a secondary atmosphere that, arguably, consisted partially of gases brought to Earth by comets.
A- consisted mainly of water, carbon dioxide, carbon monoxide, and methane
The option A, is attributed, as the composition of the secondary atmosphere, which was generated by gases trapped within the rocks that make up the planet, but escaped during volcanic activity.
Suppose that a snake handler bitten by a particular venomous snake species was treated with antivenin. Why might the same treatment for a second bite from a similar snake have different results?
The handler of the snakes has been bitten by the snake and another then he was treated with antivenin. The effect of the venom decreases and the person is well.
The handlers of the snakes if gets bitten by the same snake again then there would have been no effect on the body of the handler because the immune system of the body starts producing antibodies against the antigen.
The antigens of the snake bite would have been neutralized by the antibodies produced by the immune system of body.
A They will have sterile offspring. your welcome please 5 stars
What is the most appropriate method to prepare a sample of cheek cells for PCR?
Extraction of genomic DNA
Resuspend the cells(any number), smaller numbers also work, in 10-20 ul of TE buffer or milli Q water. boil for 5-10 min in a waterbath, quick chill, short spin. use the supernatant as a template for PCR.
If cells are very less, u can directly add cells to the PCR reaction without enzyme,boil for 5-10 min in a waterbath, let it cool slowly, short spin. Add enzyme to the supernatant and start the reaction at extension step followed by normal PCR reaction steps.
The four nucleotides found in human DNA (G, A, T, C) combine in groups of three to create potentially 64 different amino acids, but only 20 amino acids, one start codon and three stop codons are used to construct proteins. Why is this so? a.Many amino acids are not considered complete until they bind with a second amino acid.
b.64 amino acids are produced, but the body only integrates
c.42 of them into proteins. 64 amino acids are initially produced, but 42 of them are unstable and degrade immediately. Different d.nucleotide combinations code for the same amino acid.
2.What term is used to describe the phenomenon that there are 64 different groups of 3 nucleotides to code for amino acids but only 20 amino acids, 1 start codon, and 3 stop codon used in protein construction.
Suppose a male and a female with chromosomes "DD" (male) and "dd" (female) crossbreed. How likely is their offspring to exhibit the DD genotype?
4.What term best describes the genotype of "dd"?
5.Suppose a male and a female with chromosomes "DDBb" (male) and "ddBB" (female) interbreed. How likely is their offpsring to exhibit the DdBb genotype? 100% 50% 25% 0%?
6. What term best describes the breeding perfomed when a male and female with chromosomes "DDBb" (male) and "ddBB" (female) interbreed?
D- Different nucleotide combinations code for the same amino acid.
Some amino acid has more than one nucleotide combination coding for it.
Redundancy means that more than one codon is assigned for the coding of most amino acids.
Since both parents are homozygous dominant and recessive respectively, no crossing can give the homozygous dominant as all offspring are heterozygous.
The genotype 'dd' is homozygous since the two letters are both in the lower case.
If acetyl-CoA is labeled with 14C at its methyl group, how many rounds of the cycle are required before 14CO2 is released?
14 CO₂ will be released in the second turn of the cycle
Complete question goes like this, "The CO2 produced in one round of the citric acid cycle does not originate in the acetyl carbons that entered that round. If acetyl-CoA is labeled with 14C at the carbonyl carbon, how many rounds of the cycle are required before 14CO2 is released?"
The answer to this is;
- The labeled Acetyl of Acetyl-CoA becomes the terminal carbon (C4) of succinyl-CoA (which becomes succinate that is a symmetrical four carbon diprotic dicarboxylic acid from alpha-ketoglutarate).
- Succinate converts into fumarate. Fumarate converts into malate, and malate converts into oxaloacetate. Because succinate is symmetrical, the oxaloacetate can have the label at C1 or C4.
- When these condense with acetyl-CoA to begin the second round of the cycle, both of these carbons are discharged as CO2 during the isocitrate dehydrogenase and alpha-ketoglutarate dehydrogenase reactions (formation of alpha-ketoglutarate and succinyl-CoA respectively).
Hence, 14 CO₂ will be released in the second turn of the cycle.
Which of the following is the most important, publicly available, health science database? 1. PsycINFO
3. Web of Science
This is a free search engine maintained by the United States National Library of Medicine.
It is used for accessimg and searching of MEDILINE database.
Medline is an acronym for (Medical Literature Analysis and Retrieval System Online) it is conprehensive bibilography of research materials in fields of biomedicine and life sciences.It contains abstracts and references of related journals.
It is an online repository for biomedical research materials
It also helps to promotes the concept of evidence based medicine.(The concept of clincal medicine that depends on the combination of available research evidences with patients values and clincal research.)
Therefore the use of Pubmed is to gain access into all the information above in the MEDLINE.
When storing a batch of yeast starter for bread, you want to ensure that the sugar you fed the yeast is consumed slowly. Should conditions be aerobic or anaerobic? Explain using key details from your understanding of cellular respiration.
the conditions should be" anaerobic"to ensure the slow consumption of sugar i.e GLUCOSE.
the way sugar is metabolized depends on the availability of oxygen .to ensure that the sugar we fed the yeast is consumed slowly , the conditions should be made anaerobic enough .the reason for this is that in the presence of oxygen i.e in aerobic conditions the complete breakdown of glucose molecules occur and in this way glucose would be consumed much earlier.because during aerobic respiration,glucose is oxidized to CO2 and water and energy is released.
so , to consume the sugar slowly the conditions should be made anaerobic as in the case of yeast or alcoholic fermentation.
because both the alcoholic and lactic acid fermentation yield relatively small amount of energy from glucose molecules.
A genome has a GC content of 40%. Assuming the sequence is IID, what is the probability that three random consecutive nucleotides form a stop codon? Edit: IID means independently identically distributed.
The probability of three codons will be 0.063 and the nonstop codons are ATT, ATC, ACT .
The genome content = 40%
Probability of three random consecutive nucleotide to form a stop codon.
The Percentage of AT+ percentage of GC = 100.
The Percentage of AT = 100-40 = 60. [GC is given 40]
The Percentage of T = 30
The Percentage of A = 30
The percentage of G = 20
The percentage of C = 20;
The nonstop codons are ATT, ATC, ACT
So, The probability of ATT
So, The probability of ATC
So, The probability of ACT
So, the answer is 0.027+0.018+0.018 = 0.063
A DNA fragment with the sticky end sequence TGGCA will bind with another DNA fragment with the sticky end sequence _____
A DNA fragment with sticky end sequence TGGCA will bind with another DNA fragment with sticky end sequence ACCGT.
When a DNA strand is separated by the restriction endonuclease, it forms two separate single strands. These strands or cuts are known as sticky ends as they are detached from the complementary pairs.
These cuts of DNA are without complementary pairs and when they find suitable base pair, they get attached to it. These sticky ends are allowed to fix with the complementary base pairs during PCR/ polymerase chain reaction.
They are called sticky ends as they are ready to stick with the complementary base pairs of nucleotides.
The fragment of a DNA is made of the nitrogenous bases and ribose sugar and a phosphate group.
The base pairs like adenine takes place only with the thymine and guanine with cytosine. This binding is known as the complementary base pair.
The strand TGGCA will bind to the sticky end containing the ACCGT base pair. The whole strand of the DNA has complementary binding.
DNA is the genetic material in all the living beings that carries the genetic material from one generation to another generation.
A culture of human tissue is being grown in a lab to study mitosis. A solution containing radioactively labelled cytosines was added to the culture in the middle of prophase, and then growth was halted at the end of telophase. Where would the scientists see radioactively labelled DNA?
A. In the mother cells only-not in the cells produced at the end of telophase
B. Only in the nuclei of half the cells
C. In the cells produced at the end of Telophase-only in the daughter cells
D. In the nuclei of every cell
E. Nowhere in the cells
Answer: E. Nowhere in the cells
The cell cycle is an ordered set of events leading to cell growth and division into two daughter cells. The stages are G1-S-G2 (which comprise the interface of the cycle) and M. During the interface, the cell grows and synthesizes components necessary for survival (during G1 and G2), and duplicates its DNA (during S). And during M (Mitosis), the division of the nucleus into two daughter nuclei, and division of the cytoplasm occurs (the latter in a process called cytokinesis).
So, mitosis is the actual cell division, producing two genetically identical daughter cells. Each cell is diploid and contains the same number of chromosomes, because the genetic material was previously duplicated during S stage in interphase.
The stages of mitosis consist of :
- Prophase: The chromosomes move from the lax working form to the compact transport form. The nuclear envelope is fractionated into a series of tanks that are no longer distinguishable from the ER. The nucleoli also disappear, dispersing in the cytoplasm in the form of ribosomes.
- Metaphase: The mitotic or achromatic spindle appears, formed by beams of microtubules; the chromosomes join some microtubules through a lamellar protein structure located on each side of the centromere, called cinetochorus.
- Anaphase: The offspring centromeres are separated from the chromatids, which now become offspring chromosomes. Each set of daughter chromosomes migrates to one pole of the cell. The mitotic spindle is the structure that carries out the distribution of the offspring chromosomes in the two offspring nuclei. The movement is carried out thanks to the activity of the chromosomal microtubules, which are shortened at the end attached to the cinetochorus. The polar microtubules slide in the opposite direction, distancing the two groups of child chromosomes.
- Telophase: Begins when the chromosomes reach the poles of the cell. The offspring chromosomes lengthen, lose condensation, the nuclear envelope is formed again from the rough RE.
Cytosine is one of the five nitrogenous bases that make up the nucleic acids (DNA and RNA) and is represented in the genetic code by the letter C. The other four bases are adenine, guanine, thymine and uracil.
If the labeled cytosine is added during the prophase of mitosis, the DNA has already been duplicated during the S-stage and will no longer incorporate this labeled base into the molecule. So is not going to be found in either the mother cell or the daughter cells.
The vitamin _____ is a coenzyme for reactions involving nitrogen-containing compunds, including proteins and amnio acids.
Vitamin B6 (pyridoxine)
The vitamin __Vitamin B6 (pyridoxine)__ is a co-enzyme for reactions involving nitrogen-containing compounds, including proteins and amino acids.
Vitamin B 3
A sequence of nucleotides that codes for a specific protein and controls the heritable characteristics of an organism is called a(n)____________.
A sequence of nucleotide that codes for a specific protein and controls the heritable characteristics of an organism is called a(n)_____Gene_______.
A gene is the basic unit of heredity in a living organism.
Ribonucleic acid rna
After a 24 hour fast, which of the following is the major metabolic pathway providing oxidizable substrate for skeletal muscle? A. Lipolysis
C.Ketone body synthesis
Option C, Ketone body synthesis
Ketone bodies are used as a source of energy when glucose is not easily available as energy source. This usually happens when a person is fasting and hence does not intake any glucose. There are three main ketone bodies a) acetoacetate, b) 3-beta-hydroxybutyrate and c) acetone. When our body do not receive food for a long time or a person undergo rigorous and continuous physical exercise, then the level of ketone bodies increases in the blood
Hence, option C is correct
Answer: I believe the answer would be A. If it is wrong sorry.
"A man has a mutation in a mitochondrial gene encoding a subunit of the ATP synthase complex. The mutation leads to a defective ATP synthase that is not able to synthesize ATP effectively, and this in turn, leads to extreme muscle weakness in the affected individual. If this man has children, what is the likelihood that they will inherit this disease from him?
- Mitochondria is a cellular organelle that is used for the purpose of providing energy to the cell.
- This cellular organelle has a special property that it has its own DNA and hence, the mitochondrial DNA is transmitted separately from the nuclear DNA, therefore any mutation arising in the mitochondrial DNA will only be inherited if the progeny receives the mitochondria with the mutated mitochondrial DNA.
- Further, the mitochondrial inheritance in humans has a special property that only the mother transmits the organelle to the progeny.
- Since in the given question the defect in the mitochondrial gene is in the father's mitochondria and in human beings the pattern of mitochondrial inheritance is such that only the mother transmit her mitochondria to the the progeny, the offspring of the man have 0% chance to inherit the defect.
Along the length of a river there exists a species of green sunfish. In order to provide electricity to area homes, a hydroelectric dam is built that separates the lower river area from a newly formed lake above. After many, many years, the green sunfish in the river and lake are sampled and found to be phenotypically very different. Which of the scenarios listed below is the best hypothesis to explain the microevolutionary changes observed? A. directional selection
B. disruptive selection
C. stabilizing selection
D. sexual selection.
A. directional selection
In population genetics, directional selection also called as positive selection. In this type of natural selection extreme phenotype is preferred over other existing phenotype. This preference case shift in allele frequency over time in the direction of preferred phenotype.