Explanation:
Using a filtering method for the isolation of bacteria, Ivanovsky discovered that filtered sap from diseased plants could transfer the infection to healthy plants. Further researches led Ivanovsky to conclude that the causal agent was an exceedingly small parasitic microorganism that was invisible even under great magnification and that could permeate porcelain filters designed to trap ordinary bacteria.
Final answer:
Dmitri Ivanovski's experiment in 1892 crucially demonstrated that the infectious agent causing tobacco mosaic disease could pass through filters that trapped bacteria, leading to the foundation of virology and the subsequent identification of viruses.
Explanation:
The experiment conducted by Dmitri Ivanovski in 1892 marks a significant milestone in the field of virology. In his groundbreaking experiment, Ivanovski worked on the tobacco mosaic disease, previously believed to be caused by bacteria. He observed that the infectious agent could pass through a porcelain filter designed to trap bacteria. To his surprise, when he applied the filtered sap to healthy tobacco plants, they too became infected. This led Ivanovski to conclude that the agent causing the disease was smaller than bacteria and not visible under the microscope. His work laid the foundation for the discovery of viruses, although he did not identify the infectious agent as a non-living particle, which is how viruses are now classified.
Phosphate Group
Nitrogenous Base
Pentose Sugar
molecule. What is it the monomer of?
Answer: Nucleotide
Explanation: It is a monomer composed of the following parts: a phosphate group, a nitogeneous base either ( A,G,C,T) and a pentose sugar.
An example of a land feature formed by river erosion is
a.
alluvial fans
c.
soil
b.
deltas
d.
oxbow lakes
Please select the best answer from the choices provided
A
B
C
D
Answer:
An example of a land feature formed by river erosion is alluvial fans
Explanation:
Alluvial fans entails when water caused an erosion on land and makes it to form a likely shape of triangle.
Answer: D
Explanation:
Erosional landforms include V-shaped valleys, interlocking spurs, waterfalls and gorges. Meanders and oxbow lakes are formed from erosion and deposition. Depositional landforms include floodplains
What happens when the atmosphere interacts with the lithosphere?
Answer:
A
Explanation:
Gases are released from volcanic eruptions.
And took test (:
1. Describe the pattern of air circulation between an
area of low pressure and an area of high pressure.
Answer:
The sinking of cold air creates regions of high pressure and this air travels to lower pressure regions produced by the rising motion of warm air. This process results in air circulation.
Explanation:
PLEASE HELP
Read the passage and answer the following question.
Antibiotics are drugs used to treat bacterial infections. This class of drug was first developed in the 1920s. At that time, infectious diseases were the leading cause of death worldwide. Within two decades of the introduction of antibiotics, almost every major bacterial disease could be effectively cured with an antibiotic. In the late 1960s, Surgeon General William Stewart reported to Congress that infectious diseases would soon be a thing of the past. Little did he know that the process of natural selection would soon prove his words false.
As antibiotics were dispensed for practically every ailment, some bacteria developed mutations that allowed them to become resistant to specific antibiotics. Through natural selection, these bacteria rapidly multiplied and spread, effectively neutralizing the effectiveness of one antibiotic after another. Today, strains of bacteria that cause tuberculosis, staph infections, and other infectious diseases are almost completely untreatable with antibiotics. Experts predict that the problem will continue to grow and can only be held in check by the discovery of new drugs.
Using evidence from this passage explain how bacteria provided an example of natural selection.
The bacteria which had mutation became resistant to the antibiotic and survived and keeps on increasing, promoting natural selection.
Explanation:
The bacteria rapidly divide, the chances of mutation in the gene increases manifold.
The strains of bacteria causing tuberculosis and staph infection got mutated at DNA level such that they became resistant to antibiotics when tested those susceptible did not survive. These mutations were not harmful to bacteria and the resultant bacteria survived.
These bacteria which survived and proliferated as the environment was in their favour.
Thus, Darwin's Theory of Natural Selection is acceptable here as it says if a mutation is occurring towards the increase in population, they will be selected ones.
One way to increase the number of organisms in an endangered species is to let the few remaining individuals o
that species breed. However, this breeding may also lead to species extinction because inbreeding over a short
period of time may -
F produce a different species
increase fertility
o increase beneficial mutations
o reduce genetic diversity
2m
Chrome OS System
Sign-in has changed
Final answer:
Inbreeding among the remaining individuals of an endangered species may lead to a reduction in genetic diversity, causing inbreeding depression and increasing the risk of extinction.
Explanation:
One concern with allowing the few remaining individuals of an endangered species to breed is that it may lead to a reduction in genetic diversity. Inbreeding, which is the mating of closely related individuals, can often cause adverse effects known as inbreeding depression. This mating strategy tends to bring together deleterious recessive mutations, which can result in abnormalities and increased susceptibility to diseases. For example, if a rare recessive allele causing disease is present within a population, the likelihood of two carriers mating and passing the disease to their offspring increases dramatically when the population size is small and inbreeding occurs. Therefore, the option that correctly completes the statement on how inbreeding over a short period of time may lead to species extinction is through the reduction of genetic diversity.
Drag each tile to the correct location on the chart. Each tile can be used more than once.
Categorize each mutation by its most likely effect on the organism.
harmful
beneficial
neutral
Genetic Mutation
Effect
A mutation in the HBB gene, which codes for
hemoglobin, produces red blood cells that
are rigid and sickle-shaped
A mutation in the EYCL3 gene, which helps
regulate eye color, produces two
different colored eyes.
A mutation in the CFTR gene, which codes
for a cell transport protein, causes a buildup
of a thick mucus that covers the organs.
A mutation in the LRP5 gene, which codes
for a cell membrane protein, increases
bone density
beneficial
Reset
Next
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Answer:
Mutations are errors in genetic information and code that cause physical and functional alterations in living organisms. Some of them may be beneficial, harmful, or not produce significant alterations (neutral).
Explanation:
When categorizing each mutation as beneficial, harmful, or neutral, it's observed that:
A mutation in the HBB gene, which codes for hemoglobin, produces red blood cells that are rigid and sickle-shaped and is harmful.
Sickle cell anemia is caused by the HBB gene mutation, producing crescent-shaped cells, or "YES", which are not functional and very short-lived, causing hemolytic anemia. Deformity in red blood cells can cause blockage of small-caliber arteries, causing other symptoms other symptoms related to the disease.
A mutation in the EYCL3 gene, which helps regulate eye color, produces two different colored eyes, is neutral.
Under normal conditions, EYCL gene determine the color of the eyes. A mutation of this gene can cause the same individual to have a green and blue eye, which is not a serious health problem, but rather aesthetic.
A mutation in the CFTR gene, which codes for a cell transport protein, causes a buildup of a thick mucus that covers the organs, which represents a harmful mutation.
Cystic fibrosis, a disease caused by a mutation in the CFRT gene, produces the excessive thick mucous secretion that lines up the lungs and other organs - liver, pancreas, intestine - that characterizes this condition.This causes a functional alteration of the affected organ. It is also known as mucoviscidosis.
A mutation in the LRP5 gene, which codes for a cell membrane protein, increases bone density, which can be harmful, when it produces symptoms or beneficial.
Increased bone density is called osteopetrosis, and depends on the LRP5 -Low density lipoprotein receptor-related protein 5- gene mutation, that can cause bone pain in childhood and adolescence in just over half of patients, but represents an increase in bone resistance and reduces the risk of fractures.
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The heat from the Sun reaches Earth through convection.
Please select the best answer from the choices provided
T
F
Answer:
false 100%
Explanation:
A grown tiger began its life as a single fertilized egg. Which explains why a tiger
looks so much different as an adult than it did as a single fertilized egg.
All the genes are expressed.
Different genes are expressed at different times
Different cells have different genes.
As a tiger grows his genes change.
Answer:
As a tiger grows his genes change
Explanation:
Development from a fertilized egg to a mature organism depends on the expression of different genes at different times. In addition, gene expression can occur in different parts of the body at different times during development. As the fertilized egg begins to divide, different genes are either turned on or off. The activation of specific genes is the most important step in cell differentiation. As the tiger grows and develops, different genes are either turned on or off in the tiger’s various cells. This regulation is a key part of development and differentiation.
which is the best procedure of separating a mixture of maize bean and sugar
Answer:
here are several methods of separating mixtures. The common ones are:
1. Winnowing
The wind is used to separate wharves (chaff), small sticks, and dry leaves, from grains or seeds by blowing the chaff away.
Chaff is usually lighter than the grains.2. Sieving
a sieve is used to separate mixtures of particles of different sizes. For example stones from flour.
The larger particles remain on the sieve while the finer ones pass through.
3. Picking
Here the large particles are separated from smaller ones by observing them and using the hands to remove the unwanted ones.
For example, stones are separated from rice or beans in this way.
4. Filtering
This method is used to separate a liquid from particles that cannot dissolve in it.
For example, separating sand from water using filter paper or piece of cloth.5. Decanting
This is when a liquid is separated from large particles of solids by pouring the liquid out gently.
For example, pouring off kerosene that has mixed with tiny ball bearings.
Explanation:
The best procedure for separating a mixture of maize, bean, and sugar involves physical and chemical separation techniques such as hand picking, sieving, magnetism, dissolving, filtering, evaporating, and density gradient.
Explanation:The best procedure for separating a mixture of maize, bean, and sugar is using a combination of physical and chemical separation techniques. Here is a step-by-step process:
Separate the large particles by hand picking or using a sieve to remove any visible pieces of maize, bean, and sugar. Use a magnet to separate any iron filings that may be present in the mixture. Add water to the mixture to dissolve the sugar. The sugar will separate from the maize and bean. Filter the mixture to remove the liquid portion, which will contain the dissolved sugar. Evaporate the water from the filtrate to obtain pure sugar crystals. Separately, use a density gradient technique to separate the maize particles from the bean particles. The maize will settle at the bottom, while the bean will float on top. Remove the floating bean particles and collect the settled maize particles. Learn more about Separating mixture of maize, bean, and sugar here:https://brainly.com/question/24945228
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What the central idea of against all odds Earths fragile pioneers
Answer:
The central idea of "Against all odds: Earths fragile pioneers" is how Hawaii which is the most isolated island group on earth slowly was colonized by plants and animals.
Explanation:
Despite Hawaii's seclusion from the world, life got there through three means: wind,wings and water.Insects and seeds travel on birds that migrate or flee storms.Jet stream causes wind to move from Asia to Hawaii carrying seeds.And sometimes insects like cricket, and various seeds like hala reached Hawaii floating on the ocean.All these organisms faced harsh conditions, adapted and and now colonize Hawaii.Answer:
he Hala seeds can float in the ocean for so long because they have a blanket of spongy material, which help is Hala seeds float. I know this because in the text it says “How do its seeds survive the salty ocean? They are snuggled in a blanket of spongy material, which can float in the sea for months or even years. A species of Hawaiian crickets rafted in on pieces of floating wood. This supports the central idea because it shows how difficult it is for the colonize to get to Hawaii.
Explanation:
what’s the difference between a dominant allele and a recessive allele
Answer:
key difference between dominant and recessive alleles is that dominant alleles are the alleles that give the phenotype, masking over the other phenotype, while recessive alleles are the alleles that are suppressed by the dominant allele.
Explanation:
Final answer:
A dominant allele is expressed in an organism's phenotype even if only one copy is present, while a recessive allele is only expressed if two copies are present. This expression pattern determines the visible traits, with dominant alleles masking recessive ones in heterozygous individuals.
Explanation:
Difference Between Dominant and Recessive Alleles
The main difference between a dominant allele and a recessive allele lies in their expression in an organism's phenotype. A dominant allele is always expressed in the phenotype even if just one copy is inherited. In contrast, a recessive allele can only be expressed in the phenotype if two copies are present. This means that in a heterozygous individual (one who has different alleles at a particular gene locus, such as 'Aa'), the dominant allele (A) will mask the expression of the recessive allele (a).
As an example, if we consider the ABO blood group system, an individual inheriting one allele for blood type A and one for blood type O will have the blood type A because A is dominant over O. Meanwhile, for a person to have blood type O, a recessive trait, they must inherit two O alleles.
It is important to understand that dominance does not imply superiority or higher frequency in the population but simply reflects the mechanism of inheritance and expression of certain characteristics. Indeed, the same allele can be dominant in relation to one allele and recessive to another, illustrating the context-dependent nature of these terms.
What is the probability that a mother with type AB blood and a father with type O blood will have a child with type O blood?
Each parent has a 50% chance of passing down the O gene. So each child has a 25% chance of ending up with an O blood type.
Can AB and O produce AB?An AB and O couple producing an AB child cannot be explained in terms of the usual inheritance patterns. One would not expect the cord blood result to be AB when the mother is type O.
Thus, there is 25% possibility.
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Name
Class
Date
Biology/Life Sciences Standards: Genetics
Amino acids
IRNA
Growing protein
III - Anticodon
UGU
GU
mRNA
CCA (ACA) CÁC CUU CCG GGA CCU CÁC CCC CUA AGU
Codon
Fiqure 2-10 Translation A protein molecule is synthesized on a ribosome
when tRNA translates the genetic information in mRNA.
Review Questions
30 Genetic information is contained
in code words. Each code word con-
sists of three
A amino acids.
B nitrogen bases.
C codons.
D anticodons.
Which statement is true about
TRNA?
A It transcribes genetic informa-
tion in DNA.
B It translates genetic information
in mRNA
C It transfers amino acids to the
nucleus.
D It transfers mRNA to a
ribosome.
311
Where is the genetic information in
mRNA translated into a sequence
of amino acids?
A in the nucleus
B inside a DNA molecule
con a ribosome
D in a complementary base
Answer:
30.
B. nitrogen basesB. It translates genetic information in mRNA31.
C. On a ribosomeExplanation:
Translation:
Translation is the final step in the central dogma of molecular biology that involves the decoding and translation of the codons on mRNA to amino acid sequence.The genetic code is a scheme of 64 triplet nitrogeneous base codons that code for 20 amino acids.A tRNA molecule reads this codon sequence with the help of complementary anticodons and helps transport an amino acid to the ribosome for addition to the growing polypeptide chain.Protein synthesis occurs in the rough endoplasmic reticulum (RER) in the cytoplasm.What does dormancy mean
Answer:
dormancy is the state of having functions slowed down for a period of time.
Growing rain gardens like the one shown here is one way communities can help the environment. These shallow gardens contain
native plants with deep roots, wild grasses, and flowers. They are established near runoff sources, like driveways, to catch rainwater
before it flows into sewers and ditches. Capturing clean rainwater helps replenish local groundwater, instead of going to waste down
a sewer. Rain gardens naturally infiltrate water that may have picked up chemicals from lawns, roofs, or driveways while also
providing a habitat for local wildlife. Based on this information, what is another environmental benefit of rain gardens?
es )
They absorb air pollution caused by local factories.
They prevent weeds from killing non-native plant life.
They provide native fruits and vegetables for farmer's markets.
They soak up excess water that can potentially lead to flooding.
Submit
Ecology and Interdependence
Please help
A)they absorb air pollution caused by local factories
B)they prevent weeds from killing non native plant life
C)they provide native fruits and vegetables for farmers markets
D)they soak up excess water that can potentially lead to flooding
Answer:
The correct option is D) They soak up excess water that can potentially lead to flooding.
Explanation:
A rain garden can be described as a depressed area in a landscape which comprises of plants like native shrubs and flowers. The primary purpose of building a rain garden is to hold and soak in rainwater. This causes to prevent a situation such as a flood because most of the excess water is trapped by the plants. Hence, situations such as erosion and flooding can be decreased by rain gardens.
Below are the three main organs that make up the plant body.
The parts of a plant are labeled. The top green leaf part is labeled A. The stem is labeled B. The part that is underground is labeled C.
What is the main function of the structure that is identified as B in the picture above?
It anchors the plant.
It produces food.
It absorbs nutrients.
It supports the plant.
The answer isn't B. I think the answer is D.
The law of superposition states that layers of sedimentary rock are
A.
ordered in a repeating pattern, with every third layer being identical.
B.
ordered in a time sequence, with the oldest layers on the bottom and the youngest on top.
C.
ordered according to the age of the volcano that created the layer.
D.
ordered in a random fashion, with the age of the rock varying wildly from one layer to the next.
Sedimentary Rock layers over time and if there is a cliff area where you can see all the layering, there is no rhyme or reason to it, just simply grows with time. B
What is the product of a DNA synthesis reaction?
Answer:
The product of the DNA synthesis reaction is that, from a DNA molecule, two identical molecules of this nucleic acid are obtained.
Explanation:
The DNA replication process involves a series of events that result in obtaining two DNA molecules with the same sequence of nitrogen bases relative to the original. This must occur previous to the process of cell division, so that each cell daughter possesses the same genetic information.
For this process to occur the double DNA chain must be unrolled and, from each of the simple chains a complementary chain is formed, by adding complementary nitrogen bases: adenine with thymine and cytosine with guanine. DNA synthesis is facilitated by the action of the enzyme DNA polymerase.
DNA synthesis is called semi-conservative, as each molecule obtained in the process has a simple chain, coming from the original molecule, and a new synthesized chain.
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Final answer:
The product of DNA synthesis is two identical DNA molecules, comprised of one original strand and one new strand. This replication process ensures genetic information is preserved.
Explanation:
The product of a DNA synthesis reaction is two identical DNA molecules, each consisting of one original and one newly synthesized strand. This process, known as replication, occurs within the nucleus of a cell during the S phase of the cell cycle. Enzymes such as DNA polymerase play a pivotal role in this process, 'unzipping' the original double helix to use as templates for synthesis. Free deoxynucleoside triphosphates (dNTPs) are aligned opposite their complementary bases on each template strand, and DNA polymerase catalyzes the addition of these nucleotides to the 3' end of the growing chain. Thus, each daughter DNA molecule is an accurate copy of the parent DNA, ensuring genetic information is preserved during cell division.
In nature, animal populations are dynamic. This means they are changing due to various circumstances. The population of rabbits in certain areas of the world are affected by the population of foxes, for example. Using reasoning, which model shows the relationship between the two populations?
Answer:
The model representing this relationship is : Prey-Predator Relationship.
Explanation:
In a prey-predator relationship, the population size of each, prey and predator is affected by the population of the other.This is distinctly observed when the predator has a preference for a particular prey.In the given example, the rabbits are the prey and the foxes are the predators.Increase in the population of the rabbits will make them easily accessible to the foxes, that on hunt them for their food. On obtaining sufficient food the foxes can reproduce well and will produce more offspring, so the population size of the foxes would also increase.After some time, the continued hunting of the rabbits will cause its death rate to increase more than its birth rate. This will result in the decline in the rabbit population.The reduced rabbit population would reduce the chances of them being accessed and hunted by the foxes. Due to decrease in food availability, the foxes reduce their reproduction rate, as a result the fox population gradually decreases.This is followed by an increase in rabbit population.This cycle continues.Which statement BEST describes a scientific theory?
OA) No scientists believe it is correct.
OB) A few scientists believe it is correct.
OC) Many scientists believe it is correct.
OD) All scientists believe it is correct.
I think C. Many scientists believe it is correct. because a theory can not be proven therefore some we'll educated scientists could still reasonably believe the theory to be false, even when I hasn't been proven incorrect.
What are the characteristics of the reproductive strategy shown in the image?
protection from predators
low parental involvement
high percentage of offspring reach reproductive age
offspring independent after birth
(Image contains a Dog surrounded by her puppies)
Answer: In that case the right option is protection from predators.
Explanation.
Dogs protect their puppies from predators, there are many kinds of predators that are threats to domestic or guard dogs. For example, the two main types are birds of prey and coyotes. They are excellent hunters especially of the dogs and cats weighing less than 25 pounds. They can easily took dogs of smaller sizes for which the mother dog always protect her puppies from predators when they are small. Dogs have the strong instinct of protection for the survival of their off springs.
Answer:
protection from predators
I hope this helps
What two types of cells contain chloroplasts?
Answer:
The two types of cells those contain chloroplasts are plant cells and algae.
Explanation:
Chloroplasts are double membrane bound cell organelles of plant cell which has envelope, stroma and lamellar system. It is found in green plants and algae as a photosynthetic apparatus. It contains chlorophyll which is a photosynthetic pigment that receives the energy from sunlight to converts it into the energy molecules called ATP. The shape of chloroplast is variable ; most common is discoid.Final answer:
Plant cells and algal cells are the two types of cells that contain chloroplasts, which are organelles responsible for photosynthesis.
Explanation:
Two types of cells that contain chloroplasts are plant cells and algal cells. Chloroplasts are special organelles where the process of photosynthesis takes place, using chlorophyll to convert solar energy into chemical energy in the form of glucose, which serves as food for the plant. In addition to plant cells, some groups of eukaryotes called algae also contain cells equipped with chloroplasts. Like plant cells, algal cells can have one or more chloroplasts, which are important for their photosynthetic activities.
Photosynthetic cells in plants are typically found in the mesophyll, the middle layer of cells in leaves. In aquatic environments, algae harness light energy with the help of chloroplasts as well. The presence of chloroplasts is fundamental to these organisms, as it allows them to produce their own food through photosynthesis, defining their role as autotrophs within ecosystems.
Phosphate sugar base what molecule is that?
Answer:
nucleotides
The DNA molecule is a polymer of nucleotides. Each nucleotide is composed of a nitrogenous base, a five-carbon sugar (deoxyribose), and a phosphate group.
Explanation:
I need help, please
The solution regarding the Mechanical waves and electromagnetic is discussed below:
The difference between the Mechanical waves and electromagnetic waves is Mechanical waves require medium and electromagnetic waves do not.The example which describes the production of a longitudinal wave and the motion of particles that transport in the waveform is a single pulse tone is sent from an underwater speaker through a pool of water and the water molecules are compressed in the direction of wave.The similarity between the em waves and mechanical waves are transfer matter over long distances.In a compression waves, the medium is displaced in the same direction. The light bulb can generate waves and travel through the vacuum. The unique properties of EM waves are amplitude and frequency.
Which of the following choices is not evidence supporting the theory of plate tectonics?
fossil assemblages is NOT evidence supporting the theory of plate tectonics.
Explanation:
Supporting evidence of tectonic plate movements include;
ancient cave drawing found in Francethe jigsaw puzzle-like fit of the continentstraces of glaciation found in Africa and South AmericaRather than fossil assemblage, similar fossils of a species found in different continents straddling a vast ocean are evidence of tectonic plate movement.
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Answer:
its B
Explanation:
trust
4. What determines muscle strength?
Answer:
Having more fast-twitch muscle fibers is one factor that contributes to muscle strength. Another factor that determines strength is muscle mass. People with larger muscle cross-sectional areas can generate greater amounts of force. This should come as no surprise.
Explanation:
In your opinion, what are the main factors that cause pollution?
Answer:
I my opinion i think that the main causes of pollution is planes and cars as they use fuel to run. Deforestation is one major factor as there less trees to absorb the CO 2 (Carbon Dioxide). burining fo fossil fuels can also lead to many polluted areas
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Which sentence best shows the results of a substitution mutation in the DNA
Answer: Swapped nucleotide during the DNA replication.
Explanation:
For example, during replication, thymine nucleotide must be inserted in a place of guanine nucleotide.
what method can scientists use to determine when the fossil above appeared on earth?
Answer:
There are two ways
1) By the depth at which the fossil was found(i.e. If it was found near the surface of Earth, then its a fossil which was just recently decomposed, but if it was deep inside then it's old.
2) By method of Carbon Dating
Answer:
-relative age dating
Explanation:
t meant that scientists could suddenly establish the actual ages of all their rocks and fossils! The method of using radioactive decay to determine the age of rocks is called radiometric dating.
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