The factors make sequencing by the sanger chain-termination method possible are option C and E: A DNA strand whose 3' end terminates in a dideoxynucleotide cannot be elongated.
Deoxynucleotides having hydroxyl groups at the 3′ position on the deoxyribose ring make up the chain. By joining the phosphate of the incoming nucleotide to the 3′-hydroxyl of the outgoing nucleotide, DNA polymerase adds the following nucleotide. A nucleotide chain cannot continue if it lacks the 3′-hydroxyl, and the chain is broken. A growing DNA strand only gets new nucleotides at the 3' end. This is because the strand elongates only from 5' to 3' end of the chain.
Similar to DNA replication, chain termination sequencing needs deoxynucleotides, a single-stranded DNA template, DNA polymerase, and a primer. These elements are combined during in vitro sequencing operations, and DNA polymerase creates several copies of the original template.
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Which factors make sequencing by the sanger chain-termination method possible? select all that apply.
a. Complementary single-stranded nucleic acid sequences can come together to form a duplex molecule.
b. Single-stranded nucleic acid molecules can be immobilized on certain types of filter paper.
c. A DNA strand whose 3' end terminates in a dideoxynucleotide cannot be elongated.
d. Duplex nucleic acid molecules can be separated by size by means of electrophoresis.
e. New nucleotides are added only to the 3' end of a growing DNA strand.
what term would best describe the expression of the gal10 and gal1 genes in a strain that is gal80-?
Best represents the expression of the gal10 and gal1 genes in a strain that constitutively expresses gal80
constitutively expresses gal80 and Saccharomyces cerevisiae GAL80 gene (SGDID:S000004515) is a negative regulator of the transcriptional activator GAL4 from Saccharomyces cerevisiae. Dimers of GAL80 bind to GAL4 dimers, allowing GAL4 to bind UAS sequences but not to activate transcription (adapted from FBrf0233764). If GAL4 is the canonical on-switch for almost all transgenes of interest, GAL80 is the logical off-switch. GAL80 binds to the transcriptional activation domain of GAL4, thereby preventing recruitment of RNA polymerase (Ma and Ptashne 1987). Gal3 binds Gal80 more strongly than Gal1, indicating changes in adaptive proteins after replication. Molecular Biology and Evolution | Oxford Scholar.
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Identical copies of chromatin held together by cohesin at the centromere are called _____.
Histones are identical copies of the chromatin that cohesin holds in place at the centromere.
What are histones, and what are their purposes?A histone is indeed a protein that gives chromosomes structural support. The lengthy DNA molecules that make up each chromosome must fit inside the cell nucleus. The chromosome takes on a more compact shape as a result of the DNA wrapping around complexes containing histone proteins.
Are histones crucial?DNA is shielded against tangle formation and damage by histones. Additionally, histones are crucial for DNA replication and gene control. Chromosomes' unraveled DNA would be exceedingly lengthy without histones.
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4. In South America, Africa and Australia fossils of the same exact extinct amphibian
can be found. Which of the following statements best describes this occurrence?
Occurrence of endemic species in South America and Australia is due to continental drift. Continental drift is the gradual movement of the continents across the earth's surface.
Darwinism claims that the fossilized remains of South American species are similar to those found in Africa and Australia.
Thousands of animals and plants were gathered and described by Darwin during the Beagle's trip (1831–1836). He studied how species in South America adapted to a range of environments, including rainforest, grassland, and mountain ecosystems. The species in the temperate areas resembled the species of South America's tropical regions more than they did the similar species of Europe's temperate regions. For instance, although there are no rabbits in Argentina's grasslands, there are rodents that resemble them. These rodents are not linked to European rabbits, but rather to other rodents found in South America.
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although both ends of a microtubule can gain or lose subunits, one end (called the plus end) polymerizes and depolymerizes at a higher rate than the other end (the minus end). for spindle microtubules, the plus ends are in the center of the spindle, and the minus ends are at the poles. motor proteins that move along microtubules specialize in walking either toward the plus end or toward the minus end; the two types are called plus end-directed and minus end-directed motor proteins, respectively.
Microtubules can gain or lose subunits at both ends, but the plus end polymerizes and depolymerizes more quickly than the opposite end (the minus end). The plus ends of spindle microtubules are located in the spindle's centre, and the minus ends are located at its poles.
Where is a spindle microtubule's plus end located?Microtubule minus ends are located at the spindle poles, whereas microtubule plus ends connect to protein complexes called kinetochores that are attached to centromeric DNA.
During anaphase, how does the microtubule depolymerize?There are two main hypotheses about how chromosomes move during anaphase A. One is that motor proteins at the kinetochores pull chromosomes along kinetochore microtubules using energy from ATP hydrolysis.
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If a cell is no longer able to differentiate into any type of tissue, it has become ________.
A cell has differentiated if it can no longer develop into any particular tissue type.
What exactly are tissues and what varieties are there?Overview. The four fundamental types of tissue are connective, epithelial, muscular, and nervous. Supporting and tying together bone, blood, or lymph tissues is connective tissue. The linings of the body's numerous passageways, including the skin, are made of epithelial tissue.
What role does tissue play?Tissue is a collection of cells that function as a single unit with a common structure and function. The body's tissues give it form and aid in storing energy and preserving body heat. There are four different types of tissues: epithelial, connective, muscle, and nervous tissue.
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when using the hill equation:a.it will never be 1 for a multisubunit protein.b.it is possible to observe positive cooperativity.c.it cannot be applied to noncooperative binding.d.it is possible to observe both positive, negative and no cooperativity.e.it is possible to observe negative cooperativity.
when using the hill equation, it is possible to observe negative cooperativity.
What is negative cooperativity?Negative cooperativity is a phenomenon in which binding of one or more molecules of a ligand to a multimeric receptor makes subsequent ligand molecules more difficult to bind. Negative cooperativity can make the response of a multimeric receptor more graded than it would otherwise be. Negative cooperativity occurs when the binding of a first ligand or substrate molecule reduces the rate of subsequent binding. This definition does not apply only to ligand-receptor binding; it applies whenever two or more molecules have two consecutive binding events. Negative cooperativity occurs when the binding of a first ligand or substrate molecule reduces the rate of subsequent binding.
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the biological species concept emphasizes that: group of answer choices species are interbreeding entities that occupy diverse geographic areas species are reproductively isolated from each other species are irreducible clusters of organisms species are a nonsensical concept in evolutionary biology
The biological species concept would emphasize that species are reproductively isolated from each other.
So, the correct option is B.
The biological species idea stresses group separation for reproduction and is based on behavioral evidence. The lineage-species idea, which is based on genetic data, highlights unique evolutionary paths across groups that produce separate branches on a phylogenetic tree. According to the biological species concept, a species is a collection of populations that, when living together in nature, have the capacity to interbreed and give birth to live, fertile offspring but do not tend to breed with other populations.
The study of reproductive isolating mechanisms is essential to understanding the biological concept of species because these mechanisms act as physical barriers to gene flow, defining the boundaries of the reproductive community and gene pool while also maintaining the integrity of the species' genetic makeup.
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One group of rabbits lives in a forest in New York. Another group
of rabbits of the same species lives in a forest in Connecticut. Are these two
groups of rabbits part of the same population? PLS Help (Por favor)
Darwin studied two different types of tortoises on the galapagos islands. Sort the characteristics based on which tortoise they describe.
The characteristics of tortoise that Darwin describes include lengthy necks in saddleback tortoises and short necks in domed tortoises.
Darwin observed that many species of tortoises resided on islands with various climatic conditions. He understood that the tortoises possessed characteristics that enabled them to survive in their specific settings. For instance, the shells and necks of tortoises that consumed plants close to the ground were rounded.
The two varieties of Galapagos Island tortoises will be divided into the following groups:
Saddleback Tortoises have lengthy necks, elevated plant life, and rounded shells. While short necks in domed tortoises, ground-level plants, and ordinary shells.
It should be noted that the term "Galapagos tortoise" refers to a chelonoidis family member. The largest species of tortoise are known to exist. They have a maximum weight of 417 kg.
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if all chromosomes are not attached to the mitotic spindle at the m phase checkpoint, the cells would most likely be arrested at which of the following points in the cell division cycle or mitosis?
Answer:
It should be Metaphase
Match the following answers
In which phase of the cell cycle interphase
are chromosomes duplicated
(DNA is copied)
Which types of human cells use
mitosis to make more cells?
If a somatic cell has a diploid
chromosome number of 20, then
after mitosis is complete each of
the new resulting cells will have
this many chromosomes
A
w
25
S
H
YOU WON'T USE
ALL OF THESE
20
prophase
Skin
cells
Bone
Cells
10
Egg
cells
Muscle
Cells
40
Hair Cells
telophase
Sperm
Cells
Answer:
Skin cells
Explanation:
Because skin cells are often in harsh conditions, it is important that they undergo mitosis often
13. A graduated cylinder has 20 ml (cm³) of water placed in
it. An irregularly shaped rock is then dropped in the
graduated cylinder and the volume of the rock and water
in the cylinder now reads 30 ml (cm³). The mass of the
rock dropped into the graduated cylinder is 23 grams.
a.) Find the volume of the rock dropped into the
graduated cylinder.
b.)
Find the density of the rock dropped into the
graduated cylinder.
Step 1: Write the Equation
Step 2: Substitute with units
Step 3: Solve with units to nearest 0.1
A. Volume = displcement
Therefore the rock has a volume of 10mL
B. Density = mass/volume
Therefore density = 23/10 = 2.3 per unit volume.
Measure the amount of water poured into the graduated cylinder put the object in the water and measure the amount again. The difference between the two volume measurements is the volume of the object. Then divide the mass by the volume to calculate the object's density.
To measure the volume of a large stone fill a glass measuring cup halfway with water. Put a large stone in and measure the new water level. Subtract the original volume of half a glass of water and the difference is the volume or space occupied by the stone. One way he does this is by submerging the object in a measuring cup of water and recording how much the volume increases. Convert volume to m³.
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explain the following parts to a microscope: ocular: objective: stage: coarse adjustment: fine adjustment: condenser:
The eyepiece is also known as the ocular. This area is used to view objects through the microscope. It can be accessed from the microscope's top. It has a 10x standard magnification and a 5X to 30X optional eyepiece as options.
What purposes serve microscopes?An apparatus for enlarging minute objects is a microscope. The shape of a cell, as well as its nucleus, mitochondria, and other organelles, can be seen by scientists using some types of microscopes, which even allow them to observe an object at the cellular level.
Objective: The primary lenses for viewing specimens are those mentioned above. They can be magnified between 40x and 100x. One to four objective lenses can be found on a microscope, some of which are rare-facing and others that are forward-facing. There are various magnification levels for each lens.
Stage: This is the area where the specimen is displayed for inspection. The specimen slides are kept in place by stage clips. The most popular type of stage is a mechanical stage, which enables control of the slides by allowing them to be moved mechanically on the stage rather than manually.
Fine adjustment knobs and coarse adjustment knobs: These knobs are used to focus the microscope. They are referred to as coarse adjustment and fine adjustment. Adjustment knobs come in two varieties.
Condenser: Lenses called condensers are used to gather and concentrate light from the illuminator onto the specimen. They are located next to the microscope's diaphragm underneath the stage. They are essential for producing clear, sharp images at high magnifications of 400X and higher. Image clarity increases with increasing condenser magnification. With an Abbe condenser that has a high magnification of about 1000X, more advanced microscopes are available.
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Which of the following observations best supports the claim that mitochondria evolved from once-free-living prokaryotic cells by the process of endocytosis?
A. Mitochondria produce ATP.
B. Mitochondria contain proteins.
C. Mitochondria exchange substances with the cytosol.
D. Mitochondria are surrounded by a double membrane.
Option D. Mitochondria are surrounded by a double membrane, observations best support the claim that mitochondria evolved from once-free-living prokaryotic cells by the process of endocytosis.
Prokaryotes are unmarried-celled organisms belonging to the domains bacteria and Archaea. Prokaryotic cells are much smaller than eukaryotic cells, have no nucleus, and lack organelles. All prokaryotic cells are encased by way of a cell wall. Many even have a pill or slime layer made of polysaccharides.
A prokaryote is a single-celled organism that lacks a nucleus and different membrane-sure organelles. The word prokaryote comes from the Greek within the -empire system bobbing up from the paintings of Chatton, prokaryotes had been categorized in the empire Prokaryote.
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Formulate conclusions (at least 5) about the structure of plant and animal cells, about the process of plasmolysis and deplasmolysis, using your own words.
Answer:
666
Explanation:
Dna replication occurs during the _____________ phase and cell replication occurs during the _______________ phase.
DNA replication occurs during the S phase and cell replication occurs during the interphase phase.
In interphase, there is a process of preparation and storage of energy by cells to carry out the division. During interphase, the cell nucleus (nucleus) and daughter cells (nucleolus) are visible. However, the chromosomes in the cell are not visible because they are still in the form of chromatin, which are fine threads composed of DNA, RNA, and protein molecules.
The interphase stage can be divided into three:
G1 phase ("first gap"), develops the cytoplasm (cell fluid), cell organelles, as well as the synthesis of materials to be used for the next phaseS phase, DNA replication or duplication occurs as genetic material that will be passed on to daughter cells, so that two DN terminations will be produced.G2 phase ("second gap"), DNA replication has been completed. There is an increase in protein synthesis as the final stage of cell preparation for division.Learn more about interphase here https://brainly.com/question/14130118
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A researcher while working in vitro outside cell added Helicase enzyme which resulted in the untwisting of the DNA helix But the untwisting led to strain ahead of the replication fork. Which enzyme can be added to correct this problem
Answer:
The enzyme needed is topoisomerase. Topoisomerases are enzymes whose function is to regulate the unwinding of the DNA double helix. They ensure there is no over winding or underwinding of the helix. During the replication and transcription of DNA, the double helix becomes overwound ahead of the replication fork. If left to go on, the tension created would eventually hinder the ability of DNA and RNA polymerase enzymes to continue down the strand of DNA. Topoimerases I and II enzymes correct this, ensuring the polymerase enzymes do their work smoothly.
Explanation:
Hope this helps!
What is dna sequence that serves as a recognition and recruitment site for transcription factors & rna polymerase?.
A DNA sequence known as a TATA box is found in many eukaryotic promoters. Similar to the 10 element in bacteria, the TATA box also has a function.
What section of the DNA sequence attracts transcription factors and RNA polymerase?Within promoter regions are DNA sequences known as response elements that serve as a reliable binding site for transcription factors and RNA polymerase. Proteins known as transcription factors are responsible for activating RNA polymerase, controlling, and regulating the transcription of DNA into mRNA.
What is the DNA transcription sequence?DNA sequence that acts as a recognition and recruitment site for transcription factors and RNA polymerase. Transcribing process stages. A gene's transcription occurs in three stages: start, elongation, and termination.
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the functions of the liver include
Answer:
The functions of the liver include:
Bile production and excretion.Excretion of bilirubin, cholesterol, hormones, and drugs.Metabolism of fats, proteins, and carbohydrates.Enzyme activation.Storage of glycogen, vitamins, and minerals.Synthesis of plasma proteins, such as albumin, and clotting factors.The functions of the liver include:
FiltrationDigestionMetabolism and DetoxificationProtein synthesisStorage of vitamins and mineralsExplain the functions of the liver.
Filtration: The liver filters the blood and breaks down harmful substances. The by-products are excreted into the bile or blood.Digestion: The liver plays a role in digestion by secreting bile. Bile is a fluid produced in the liver and stored in the gallbladder.Metabolism and Detoxification: The liver uses enzymes as a mode of detoxification. The liver also detoxifies the body by changing a foreign or harmful agent to urea or bile and excreting it from the body via stool or urine. Protein synthesis: Liver cells play a role in protein synthesis and amino acid metabolism, and is involved in the production of ammonia.Storage of vitamins and minerals: The liver produces, stores, and releases vitamins and minerals into the blood. Vitamins are responsible for pulling out vital elements from the foods we consume. These elements are essential for normal growth, the development of healthy red blood cells, hormones, genetic materials, and the nervous system.Thus, these points are the functions of the liver.
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I NEED HELP WiTH ALL THIS ASAP
The skeleton has been labeled based on the information given.
What is a skeleton?The human skeleton is the body's internal framework. It is made up of approximately 270 bones at birth, which decreases to approximately 206 bones by adulthood after some bones fuse together. The skeleton's bone mass accounts for approximately 14% of total body weight.
Thw body's skeletal system serves as a support structure. It shapes the body, allows movement, produces blood cells, protects organs, and stores minerals. The musculoskeletal system is another name for the skeletal system. The skeletal system also provides support to the body by acting as a framework and attachment.
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Which animal is similar to humans?
Answer:
Chimpanzees.
Explanation:
Chimpanzees now have to share the distinction of being our closest living relative in the animal kingdom
Chimpanzees now have to share the distinction of being our closest living relative in the animal kingdom. So, chimpanzees are similar to humans.
What animals are similar in form to humans?
Humans, chimpanzees, gorillas, orangutans, and their extinct ancestors form a family of organisms known as the Hominidae. Researchers generally agree that among the living animals in this group, humans are most closely related to chimpanzees, judging from comparisons of anatomy and genetics.
Why humans are also animals?
Humans can move on their own and are placed in the animal kingdom. Further, humans belong to the animal phylum known as chordates because we have a backbone. The human animal has hair and milk glands, so we are placed in the class of mammals. Within the mammal class, humans are placed in the primate order.
Thus, chimpanzees are similar to humans.
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What happens when there is an influx of
nutrients in an aquatic ecosystem?
A. there is an overabundance of nutrients
B. producers slow down their rate of production
C. nutrients become limited in that ecosystem
D. producers work in harmony to supply nutrients to the
area
which characteristic was not advantageous for organisms in the million years after the catastrophic asteroid impact?
Large body size was initially a disadvantage for organisms in the million years after the catastrophic asteroid impact.
An Impact event is a collision between astronomical objects causing measurable effects. large body size is known as a key diagnostic feature of species threatened with extinction.
In ecology, The studies between the body size and extinction has been studied in detail. The specification curves show that the body size effect on threat status tends to be less strongly impactful in models that include geographic range size as a covariant.
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which of the following is not a reptile? group of answer choices northern leopard frog marine iguana galapagos tortoise burmese python
Among all these options all of them are reptiles except for one species. The species that is not at all a reptile is northern leopard frog that is an amphibian.
What is the kingdom to which the reptiles belong ?
Reptiles belong to the kingdom animalia and the class reptilia. The more animals to which the kingdom belong are lizards, crocodiles and many more.
Amphibians (frogs) that are having four limbs and these are mostly able to live in both water and land for example in the case of amphibians it is eggs laying in water but they live on land but it is noticeable that they fertilise in water.
Therefore, the correct option is northern leopard frog.
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1. discuss the phylogenetic relationships between major clades of vertebrates (jawless fishes, chondrichthyes, actinopterygii, sarcopterygii, amphibia, reptilia,mammalia), the major characteristics of each (and adaptive value of such characteristics) and the points on the phylogenetic tree where major adaptations appeared, such as vertebral column, endoskeleton, cranium, jaws, lungs (or derivatives), lobe fins, limbs, amniotic egg and hai
Jawless fishes come under class agnatha, Chondrichthyes comes under Pisces, Actinopterygii includes ray-finned fishes, and sarcopterygian includes lobe-finned fishes.
What is a phylogenetic relationship?
It is the study of the relationship among organisms of a species or a population through evolution. It enriches our understanding of how genes, genomes, and species evolve.
Pisces has two types of vertebral column trunk and caudal vertebrae, cartilaginous fishes have cartilage endoskeleton, and bony fishes have bone endoskeletons, respiration occurs through gills, Fishes and amphibians are amniotes.
Amphibians, reptiles, and mammals have axial and appendicular endoskeletons. Amphibia, reptilia and Mammalia have dicondylic skull, four limbs, respiration through lungs, and a vertebral column.
Sarcopterygii and Actinopterygii are two groups of Osteichthyes which have a bony endoskeletons.
Hence, Pisces, amphibia, reptilia, Mammalia have almost similar characteristics that differ only in the endoskeleton.
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a gene fusion where the regulatory region of one gene is fused to the open reading frame of another gene whose protein product is easy to detect.a preferred sugar prevents transcription of a sugar-metabolizing operon.a protein that changes its conformation upon binding to another molecule, such as a repressor that binds toan inducer.stimulation of transcription by a specific molecule. prevention of gene expression by a specific protein that binds to an operator.a cluster of genes transcribed together into a single mrna and regulated as a group.premature termination of transcription in response to translation of an rna leader.an untranslated region at the 5' end of a bacterial mrna.a strain that synthesizes curtain enzymes regardless of environmental conditions.
A gene fusion where the regulatory region of one gene is fused to the open reading frame of another gene whose protein product is easy to detect reporter gene.
A gene created by combining sections of two different genes. Fusion genes and the fusion proteins that result from them can be created in the laboratory or naturally in the body when a piece of DNA from one chromosome moves to another. The most common type of mutation is gene fusions or translocations caused by chromosomal rearrangements. They result in chimeric transcripts or gene deregulation due to the juxtaposition of novel promoter or enhancer regions.
A reporter gene is an exogenous coding region that is linked to a promoter sequence or element in an expression vector and introduced into cells to provide a means of measuring promoter activity.
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When an electron is emitted from photosystem II, it does not return.The photosystem cannot trap any more light energy until the "hole" in the photosystem is filled with another electron. The source of the electron that fills the "hole" in photosystem II is
Select one:
a. carbon dioxide
b. water
C. NADPH
d. ATP
Answer:
carbon dioxide
your welcome
which of the following methods of altering enzyme activity is irreversible? phosphorylation of enzymes. binding of allosteric effectors to enzymes. binding of transition state analogs to enzymes. none of the above (all of them are reversible). binding of competitive inhibitors to enzymes.
All methods for changing enzyme activity are temporary. They are all reversible.
What is an easy way to define enzyme?
A specific kind of biological catalyst called an enzyme is almost always a protein. It speeds up a particular chemical process happening inside the cell. The enzymes are continuously employed throughout the process, and they are not wasted.
What role does an enzyme play?
Our bodies' metabolism, or chemical reactions, are accelerated by proteins called enzymes. While certain chemicals are destroyed, new ones are created. Enzymes are a part of everything living. Our bodies naturally manufacture enzymes. Names ending in -ase are frequently derived from the substrate of an enzyme or the series of events that it catalyzes.
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Suzanne has two biological sons that she raised from birth. her two sons are members of her?
The biological sons that she raised from birth. her two sons are members of her Family of procreation.
Family is the first and most important agent of socialization. Procreation comes from a Latin word procreare meaning "bring forth" It refers to the family you want to create through marriage and by having children. Families of procreation includes their own set of distinct family values. It is different from family of orientation where it is the family you were born into.
The role of family of procreation is to create children and develop their socialization. The family here created is done by the choices unlike family of orientation where we do not get to choose.
The family of procreation will form unique family values and dynamics
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The prime factorization is 3 2 ・5 2 . What number does this describe?
Answer:
scuse me but this is math