Answer:
false
Explanation:
they increase of red blood cells
explain how the various specialiesed cells are modified to Cary out to their function 20mark
A sample from a stock of a bacterial colony in liquid media was diluted by a factor of 106, and 2 ml of this dilution was spread on a Petri dish of solidified media. 56 colonies were observed. What was the concentration of bacteria of the initial stock?
Answer:
28 × 10⁶ colonies/ml
Explanation:
Let C be the concentration of bacterial in the initial stock. When it is diluted by a factor of 10⁶, the new concentration is C' = C/10⁶.
When 2 ml of this concentration is spread on a Petri dish of solidified media, 56 colonies were produced. The number of colonies, n after spreading the 2 ml of C' is C' × 2 ml = 2C' = 2C/10⁶.
So, n = 2C/10⁶.
Since the number of colonies after spreading on a Petri dish of solidified media is 56, n = 56 colonies.
So, 2C/10⁶ = 56
Making C subject of the formula, we have
C = 56 × 10⁶/2
C = 28 × 10⁶ colonies/ml
So, the initial concentration of bacteria is 28 × 10⁶ colonies/ml
Kevin's supervisor, Jill, has asked for an update on today's sales, Jill is pretty busy moving back and forth between different store locations. How can Kevin most effectively deliver an update to her ? a) Call with a quick update Ob ) Send a detailed text message c ) Book a one-hour meeting for tomorrow morning d) Send a detailed email
Answer:
d) Send a detailed email
Explanation:
Send a detailed email is the best way to deliver an update to her because in the email he can send all the information in detail form which can satisfy his owner. He can't call or message because it takes too much time to provide information so email is the best way to provide information. Booking a one-hour meeting is not worth it and the reason for this is that there is no big presentation which takes one hour of description one email is enough for it.
A DNA fragment is introduced into the lacZ gene of a plasmid, which also contains an ampicillin resistance gene. What is the appearance of bacteria transformed with this plasmid if they are spread on plates containing ampicillin and X-gal
Answer: White colonies that are resistant to ampicillin.
Explanation:
The lac operon is an operon required for the metabolism of lactose in enteric bacteria such as Escherichia coli . It has three structural genes, a promoter, an operator and a regulator, all regulated by the availability of glucose and lactose. The lac repressor, a protein, senses lactose and blocks transcription of this operon. It acts as a repressor when lactose is present. A catabolite-activating protein (CAP), on the other hand, acts as a glucose sensor. The bacterium should express the lac operon only when lactose is available and glucose is not available. Thus, genes can always be transcribed, except when the Lac repressor protein is bound to the operon region, for which it has a high affinity (i.e. in the absence of lactose), where the Lac repressor protein maintains its high affinity for the operon region, preventing RNA polymerase from transcribing the structural genes. Thus, the system remains closed with consequent energy savings for the bacterium. In the presence of lactose, it binds to the Lac repressor protein and generates a conformational change that decreases its affinity for the operator region. Thus, the operator region is left free, RNA polymerase can freely transcribe the structural genes and the synthesized β-galactosidase (an enzyme) can degrade lactose to glucose plus galactose for energy.
Thus, the lac z gene encodes the enzyme β-galactosidase, which catalyzes the hydrolysis reaction of lactose to glucose and galactose. In gene cloning experiments, a compound called X-gal is used as an indicator of cells expressing the β-galactosidase enzyme. X-gal is hydrolyzed by the enzyme to galactose and another compound that is oxidized giving an insoluble blue compound. Thus, if X-gal and a β-galactosidase inducer are dissolved in the medium of a culture plate where the transformed bacteria is found, colonies grown on the plate that possess a functional lac z gene (either because they were not transformed by the plasmid, or if they were but the plasmid does not have the cloned fragment or gene that disrupts the lac z gene) can be clearly distinguished by their blue coloration. If they have another gene inserted interrupting the lac z gene, they will not be able to produce the enzyme that degrades X-gal, resulting in white colonies since X-gal is not degraded giving that characteristic blue color.
The white, non-transforming colonies are eliminated by adding an antibiotic to the medium for which the plasmid provides resistance (in this case ampicillin), so that we can select the recombinant colonies that carry the vector with our sequence, simply by their color.
So, if bacteria are transformed with a plasmid (with ampicillin resistance) cloned with a gene that interrupts the lac z gene, the bacteria will be white because they do not synthesize the enzyme that degrades X-gal and will be resistant to ampicillin.
Natural selection can lead to evolution in a population when:
A. a new allele appears in one of the offspring in a new generation.
B. one of its individuals is able to obtain more resources than others.
C. all individuals have the same genetic traits as their parents.
D. it has genetically diverse members that compete for resources.
which of the specific classification is the specific organism found
Answer:
Species are as specific as you can get. It is the lowest and most strict level of classification of living things. The main criterion for an organism to be placed in a particular species is the ability to breed with other organisms of that same species.
According to the phenotypic characters of pneumococcus considered in Griffith's
experiment of transformation, which of the following statements are correct? Choose the
correct option (i) Presence of slime layer (ii) Presence of capsule (iii) Absence of capsule
Answer:
发发发 发斯蒂芬
Explanation:
Presence of capsule. Therefore, option (B) is correct.
What was Griffith's experiment?Griffith's experiment of transformation is a landmark experiment in microbiology conducted in 1928 by British bacteriologist Frederick Griffith. The experiment aimed to determine the nature of the "transforming principle" responsible for transferring genetic material between bacteria.
Griffith used two strains of Streptococcus pneumoniae, one that was virulent and had a polysaccharide capsule (S strain) and another that was non-virulent and lacked the capsule (R strain). He found that when he injected mice with the heat-killed S strain and live R strain, the mice died, and live S strain was found in their blood. This suggested that the R strain had been transformed into the S strain, and the genetic material was responsible for the transformation.
Griffith's experiment provided the first evidence of bacterial transformation and paved the way for future research on the molecular basis of genetics.
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In butterflies, having red antennas (denoted by “R”) is dominant to having white antennas (denoted by “r”). If both parents are heterozygous for red antennas, what are the predicted Phenotypic outcomes of their offspring? (hint: a punnett square will help you determine this).
In butterflies, having red antennas (denoted by “R”) is dominant to having white antennas (denoted by “r”). If both parents are heterozygous for red antennas, what are the predicted Genotypic outcomes of their offspring? (hint: a punnett square will help you determine this).
All the offspring of a cross between a black-eyed mendelien and an orange-eyed mendelien have black eyes. What is the expected F2 phenotypic ratio of a cross between two F1 black-eyed mendeliens?
A) 1 black-eyed:1 orange-eyed
B) 3 black-eyed:1 orange-eyed
C) 1 black-eyed:3 orange-eyed
D) 1 black-eyed:0 orange-eyed
The phenotypic ratio of the cross is as follows: 3 red antennas: 1 white antenna
For question 2, the phenotypic ratio of the F2 generation is: 3 black-eyed: 1 orange-eyed
QUESTION 1
According to the first question, a gene coding for antenna color in butterflies is involved. Red antennas (“R”) is dominant to white antennas (“r”). Hence, a butterfly with genotype "Rr" will be phenotypically red.
According to this question, If both parents are heterozygous for red antennas i.e. Rr (red antenna) × Rr (red antenna), the following gametes will be produced: R and r. Using these gametes in a punnet square (see attached image), the following phenotypic ratio of offspring is produced:
3 RED ANTENNAS (RR, Rr, Rr) : 1 WHITE ANTENNA (rr)
2. In the second question, all the offspring of a cross between a black-eyed mendelien (BB) and an orange-eyed mendelien (bb) have black eyes (Bb). In a cross between two F1 black-eyed mendeliens i.e. Bb × Bb, the following proportion of offspring is produced:
BB, Bb, Bb, bb
Hence, a phenotypic ratio of 3 black-eyed: 1 orange-eyed
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Which type of energy refers to the sum of potential and kinetic energies in the particles of a substance?
Answer:
The answer is Internal energy
KE + PE = IE
Explanation:
The sum of potential and kinetic energy is refers to mechanical energy which is expressed by motion
Answer:C for edge (internal energy)
Explanation:
ich example best shows that the chemistry of water is helpful to plants?
Water’s polarity produces a high density, which allows water to move to the leaves.
Water’s bent shape causes a slow passage of nutrients up to the leaves of plants.
Water’s polarity causes cohesion that pulls other water molecules up through a plant.
Water’s bent shape reduces its own passage through the cell membranes of roots.
Answer:
waters polarity causes cohesion that pulls other water molecules up through a plant.
I hope this helps
Explica con tus palabras el proceso de la formacion de orina
Answer:
Answer to the following question is as follows;
Explanation:
The kidneys filtration undesirable chemicals from the bloodstream and expel them through urine. Urine is formed in three stages: glomerular filtration, re - absorption, and secretion. These procedures guarantee that the bodies natural waste and surplus water are eliminated.
Partes del sistema linfatico
Answer:
Explanation:
Le parti principali del tessuto linfatico sono il midollo osseo, la milza, la ghiandola del timo, i linfonodi, i linfonodi e le tonsille.
Which of the following iS a possible future milestone in environmental policy?
a.
water pollution policy
b. implementation of a cap and
dividend policy
C.
mandatory environmental assessments
d environmental impact statements
Answer:
a. water pollution policy
Wheres the cell membrane located?
Answer:
in cells the cell membrain is located in the middel but this can vary in diffrent cells Explanation:
Which statement about the genetic code is false?
A. There is no punctuation or spacing between codons.
B. Codons are composed of sets of three nucleotides.
C. Every amino acid is specified by a single codon.
D. The genetic code is almost universal, but not quite.
The statement 'every amino acid is specified by a single codon' about the genetic code is FALSE (Option C).
The genetic code refers to the process by which the heritable information is passed from the DNA sequence to RNA during transcription, and then from RNA to protein during translation.The genetic code is said to be redundant because there are amino acids that can be encoded by more than one codon.For example, the amino acid leucine can be specified by four different codons (CUU, CUC, CUA, and CUG).In conclusion, the statement 'every amino acid is specified by a single codon' about the genetic code is FALSE (Option C).
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Bacteria break down the nitrates and release oxygen. True or false? Short answer
Answer:
True
Short Answer-Denitrifying bacteria transform nitrate in extremely wet soils and swampy grounds where there is very little oxygen, i.e. the conditions are anaerobic. The bacteria get the oxygen they need for respiration from the breakdown of nitrates.
Explanation:
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The fact that only your liver cells produce liver enzyme and not your skin cells, which contain the same DNA, can be explained by O PCR O gene expression O gene flow NA
Answer:
Gene expression
Explanation:
Gene expression is the process in which cells (usually eukaryotic) have niches , meaning that one set of genes is expressed in once cell and different ones in another
As with most fluid samples sent for microbiological analysis, Mandy starts her investigation with a Gram stain.
Gram Stain Analysis Classify the infectious agent based on the Gram staining.
Hi. Unfortunately your question is incomplete and you have not shown any photos of the sample that Mandy must identify by Gram stain. However, after researching her question on the internet, I was able to find another question exactly like this one, which showed the microorganism that should be analyzed. This image is attached below. In that case, I hope the answer below can help you.
Answer:
Gram-positive cocci
Explanation:
It is possible to identify that the microorganism presented is a bacteria due to the application of the test known as Gram stain, which allows the identification of gram positive and gram negative bacteria. This test allows the bacteria to be subjected to a specific dye that reacts with the chemical composition of the bacteria, modifying its color. Gram positive bacteria show a blue color after the test, while gram negative bacteria show a red color after the test.
As we can see in the attached image, the bacteria that Mandy is analyzing shows a blue color, after being submitted to Gram stain, being then a gram positive bacteria.
We can also see that the colonies of this bacterium have formed round, similar to a coconut and for this reason, we can conclude that the bacterium has the shape known as cocci.
Therefore, we can classify the microorganism as a Gram-positive cocci.
In mitosis, the results are 2 different haploid cells.
ASAP please!!!
Answer:
In mitosis, the results are 2 different diploid cells.
Explanation:
Mitosis is an exact replication of the parent cells, making them diploid cells. 4 haploid cells are the result of meiosis.
Answer:
When a haploid cell undergoes mitosis, it produces two genetically identical haploid daughter cells; when a diploid cell undergoes mitosis, it produces two genetically identical diploid daughter cells. ... In contrast, meiosis is considered a “reductional” form of cell division that occurs in diploid germ cells.
In the garden pea, yellow cotyledon color is dominant to green, and inflated pod shape is dominant to the constricted form. When both of these traits were considered jointly in self-fertilized dihybrids, the progeny appeared in the following numbers : 193 green, inflated : 184 yellow, constricted : 556 yellow, inflated : 61 green, constricted. Test the data for independent assortment
Answer:
IT was shown that observations of 60 : 40 produced a significant chi-square at the 5% level when uncorrected for continuity. Apply the Yates correction for continuity and retest the data.Which is a compound that allows plants to get nitrogen from the nitrogen cycle?
Answer:
Plants can use ammonia as a nitrogen source. After ammonium fixation, the ammonia and ammonium that is formed will be transferred further, during the nitrification process. Aerobic bacteria use oxygen to convert these compounds.
why is the silkworm called a useful insect?
i need help in biology questions please G10?
Answer:
ok where is it
we can help only if there is something attached
what is the full form of NADP ?
Answer:
NaDP- Nicotinamide adenine dinucleotide phosphate
What were the three large, flightless birds with similar features found on different continents, Australia, Africa, and South America?
Answer:
Rhea from south america
Emu from Australia
ostrich in Africa
What's is biosynthesis
Answer:
the part of an organism close to the flesh and the cells
Explanation:
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined together to form micro molecules. This process often consists of metabolic pathways.
At this point, the writer is considering adding the following sentence. Successful nerve impulse transmission depends not only on myelin sheaths, but also on the presence of ion pumps embedded in the cell membrane. Should the writer make this addition here?
A) Yes, because it describes how the presence of ion pumps is related to the functions of cholesterol.
B) Yes, because it supports the passage’s main argument with a second example of cholesterol’s potential adverse health effects.
C) No, because it identifies a relationship between the nervous system and ion pumps that has already been discussed.
D) No, because it interrupts the paragraph’s discussion of cholesterol’s functions with loosely related information.
Answer:
D) No, because it interrupts the paragraph’s discussion of cholesterol’s functions with loosely related information.
Explanation:
The passage was discussing the importance of cholesterol in nerve impulse transmission. Its presence in the myelin sheaths of nerve cells speeds up nerve impulse transmission. It will not be wise for the author to now bring in the relationship between nerve impulse transmission and ion pumps. This is because the main topic under discussion is cholesterol and its importance. The sentence should be continued with other importance of cholesterol and not ion pumps.
Change of a liquid to a gas is ___________.
Answer:
Condensation. think about I, if you see fog on a lake or pond, that's condensation, if you see water droplets on the side of your cold beverage, that's condensation.
Which of the following describes a parasite
1 a bear that kills and eats fish?
2 a worm that lives inside a bear.
3 a dish that is killed and eaten.
4 a bear that has worms in its gut
Answer:
2
Explanation:
A parasite is an organism that feeds on the intestine of living organiy
Which of the following pathway would a protein destined for the interior of the nucleus follow
Answer: The protein is translated on free ribosomes and then passes through the pore complex to enter the nucleus.
Explanation:
