Answer:
Oxygen levels stay above 15 percent starting 200 million years ago
Explanation:
Atmospheric oxygen levels are related to the evolution on Earth and changes in geochemical cycles that involve climate variations.
The presence of O 2 and evolution of oxygen gave new opportunities to the life on Earth. Oxygen levels in atmosphere have fluctuated between 15% and 35% of atmospheric volume, since the start of the Cambrian period.
So, form the starting 200 million years ago, oxygen level stay above 15 percent and the correct option is "B".
Answer:
b
Explanation:
Explain why mutations that replace S/T/N residues with A/L/W residues in the N-terminal region of transmembrane proteins that function as cell surface receptors could significantly disrupt that utility of these proteins as receptors.
Answer:
Serine (S), Threonine (T) and Asparagine (N) are primary binding sites of carbohydrates, and thereby they are required to form glycoproteins (i.e., glycosylation products)
Explanation:
A transmembrane protein (TP) is a particular type of protein that crosses the cell membrane in order to enable the movement of ions and molecules. Transmembrane proteins are divided into alpha-helical and beta-barrel proteins. The N-terminal region of transmembrane glycoproteins can be required for N-linked glycosylation, which is an enzymatic mechanism capable of attaching oligosaccharides to proteins in order to form glycoproteins (glycans). N-linked glycosylation is a posttranslational protein modification that has distinct functions depending on the cell type and the protein region involved in such modification. For example, in the surface of immune cells, the N-linked glycans are capable of dictating the migration pattern of these cells.
Question 9 (5 points)
How do mutations occur?
Mutations occur through the intentional alteration of amino a
Mutations occur randomly through changes in DNA.
Mutations occur through a negative change within that organ
1
Mutations occur as directed responses to changes in the envi
Answer:
The answer is option 2.
Explanation:
Mutation occurs when there is a change in DNA base sequences.
(Correct me if I am wrong)
Answer:
Mutations occur randomly through changes in DNA.
Explanation:
It's now understood that mutations occur randomly and aren't directed in response to an immediate change in the environment.
Which source would be the least reliable? a nonfiction book written by a scientist a peer-reviewed scientific journal an encyclopedia an advertisement
Describe an example of non-heritable variation. Think about the way an organism interacts with its environment and how that influences its phenotype (the nurture in nature vs. nurture). Knowing what you do about genetics, genes, and gene expression control, propose a mechanism of molecular control that might be working in the example you have chosen.
Answer:
Epigenetic reprogramming
Explanation:
Epigenetic is a discipline that studies how phenotypic traits are influenced by DNA methylation and histone post-translational modifications such as acetylation, methylation and ribosilation. All these epigenetic marks are known to affect the conformation of the DNA molecule, thereby altering gene expression patterns and consequently also phenotypic associated traits. Epigenetic reprogramming refers to the erasure and remodeling of these epigenetic marks, this being a type of non-inherited variation produced by the interaction between a genotype and its environment. Epigenetic reprogramming is in part responsible for the non-heritable differences observed between different cell types and tissues.
In imaginary fruit, white fruit color (W) is dominant over yellow fruit color (w) and disk-shaped fruit (D) is dominant over sphere-shaped fruit (d). If a plant true-breeding for white, disk-shaped fruit is crossed with a plant true-breeding for yellow, sphere-shaped fruit, what will the phenotypic ratios be for: Show all work
Answer:
See the answer below
Explanation:
Genotype of a true-breeding white, disk-shaped fruit = WWDD
Genotype of a true-breeding yellow, sphere-shaped fruit = wwdd
Crossing the two:
WWDD x wwdd
WwDd
All the offspring (100%) will have the genotype WwDd with white, disk-shaped phenotype.
Assuming the cross is advanced to F2:
WwDd x WwDd
W_D_ 9 White, disk-shaped (9/16)
W_dd 3 White, sphere-shaped (3/16)
wwD_ 3 Yellow, disk-shaped (3/16)
wwdd 1 Yellow, sphere-shaped (1/16)
(See the attached image for the Punnet's square)
What is the end result of the eukaryoic cell cycle?
A. no parent cells and two daughter cells
B. one parent cel and two daughter cells
C. two parent cells and one daughter cel
D. one parent cell and one daughter cell
Answer:
A. No parent Cells and two daughter cells
A. _____ found in the intestinal tracts of poultry and other animals; outbreaks have been linked to raw eggs, unpasteurized milk and raw or undercooked meat, poultry or shellfish; avoiding cross contamination can help prevent this microorganism from causing illness. B. _____ most often affects fetuses; outbreaks have been traced to unpasteurized milk, lunch meats and hot dogs. C. _____ found in infected cuts and in the nose and throat; outbreaks have been associated with mayonnaise based salads (macaroni, chicken, egg) and cream filled baked goods; can be prevented by proper cooling and refrigeration of foods. D. _____ found in the intestinal tracts or animals and humans; common cause of waterborne disease in humans in the United States. E. _____ found in the human intestinal tract; outbreak have been associated with salads and contaminated water; using sanitary practices can prevent illness from this microorganism.
Answer:
A Salmonella
B Listeria monocytogenes
C Staphylococcus
D Camplobacter jejuni
E Giardia intestinalis
Explanation:
The relevant term is mentioned above for filling in the blank according to the description provided. Each pathogen has a unique set of conditions required for breeding and causing infection, although some characteristics are overlapping with one another as well.
Organism found in the intestinal tracts of poultry as well as other animals, but can be prevented from causing illness by cross contamination is Salmonella.
organism that most often affects fetuses, and the cause of it is from unpasteurized milk is Listeria monocytogenes.
Organisms that can be found in infected cuts as well as in nose and throat is Staphylococcus.
microorganism that can be in the intestinal tracts or animals as well as humans which is common to waterborne disease is Camplobacter jejuni.
Microorganisms that can be found in human intestinal tract in which salads and contaminated water usually the cause of the outbreak is Giardia intestinalis.Microorganisms can be regarded as organisms that cannot be seen without microscope. Some of this organisms are dangerous fir our health while some are useful.Giardia intestinalis is one of the microbes found in human intestinal tract , it's outbreak could be as a result of contaminated water.Learn more at:
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Your mom has started complaining to you about her varicose veins and is thinking about surgery. What true information could you tell about varicose veins?
Answer:
One very true and essential information to know about varicose veins is that there is often re-occurrence following after surgery.
Explanation:
Varicose veins are a group of large, benign, twisted, and superficial veins on the skin surface. They may come with no side effect in some sufferer (asides from the physical appearance), and can cause chronic pain and discomfort in others, usually pointing to an underlying circulatory problem. Varicose veins are caused by damaged or weak valves in the veins, and complications like bleeding might occur. Some people with the risk of developing this disease are obese people, people with genetic tendencies, and usually pregnant women. Treatment methods includes compression stocking, a lifestyle change, and some medical procedures like surgery. After surgery, there is usually re-occurrence.
Fill in the blanks.
1. The phylum contains most common animals you are familiar with su
as eagles, dogs, foxes, and frogs.
2. While the earth is home to many members of this phylum, earthworms are
a member of
3. The most successful phylum on earth is which contains insects,
spiders, and crustaceans.
4. An animal that molts it exoskeleton is called a(n).
5. are cells that have the potential to become any type of cell; they hav
not yet received their genetic programming.
6. All members of the animal kingdom are multicellular, heterotrophic and
7. A starfish is a bilaterian deuterostome with symmetrical adults.
8. Complete the chart by describing what kinds of organs or tissues each type
germ layer becomes:
Moi
Answer:
1. chordata
2. nematoda
3. arthropoda
4. ecdysozoan
5. stem Cells
6. eukaryotic
7. radically
Chart answer:
Endoderm = Lungs, liver, pancreas, lining of gut organs
Mesoderm = Bone, muscle, heart, circulatory system
Ectoderm - Brain, nervous system, skin
Explanation:
Answer:
1. chordata
2. nematoda
3. arthropoda
4. ecdysozoan
5. stem Cells
6. eukaryotic
7. radially
8. Endoderm… Mesoderm becomes… Ectoderm becomes…
Lungs, liver, pancreas, lining of gut organs
Bone, muscle, heart, circulatory system
Brain, nervous system, skin
Explanation:
Natural resources are not required for all energy producing technology
Please select the best answer from the choices provided
ОТ
OF
Answer:
True
Explanation:
we don't need only natural resources to produce energy but artificial resources too.
Hope it helps.
Natural resources are required for all energy producing technology. So, the given statement is False.
What is Energy production?The area of endeavours centred on obtaining energy supplies from natural resources is known as energy development. These activities include the creation of energy from fossil, nuclear, and renewable sources as well as the recovery and redistribution of energy that might have been lost.
The creation of energy requires a source. We cannot produce something without using natural resources, whether they are renewable or not. This is true whether the sources are renewable or not. For instance, radioactive minerals are required to operate nuclear energy.
Similar to how water, air, renewable power, coal, fossil fuels, natural gas, or any other source we choose are all already existing in nature, natural resources are needed for every energy-producing technology regardless of the industry we choose.
So, the given statement is False.
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Michael, a new lab analyst, receives an email notifying him that his expected samples from a recent outbreak should be arriving soon. To prepare for his analysis, he decides to look into what type of diseases could be spread between animals and humans, as this is a new field for him. Michael has received limited information about the details of the outbreak from the epidemiologists that traveled to the site, but he does know that both animals and humans were infected by some type of virus. Michael looks through some of the lab manuals on how the samples will be handled once in the lab. While reading through these guidelines, he realizes that there are some terms he is not quite sure of.
Below are sentences that reflect the terms that Michael had to acquaint himself with while reading through the published guidelines from his laboratory. Please review the sentences below and fill in the blanks with the correct word(s).
a. arthropods
b. togaviruses
c. encephalitis
d. arbovirus
e. flaviviruses
f. zoonosis
A virus that is able to be transmitted via _________like ticks, flies, and mosquitoes is considered __________.
2. Some arboviruses are able to move through the bloodstream and infect the brains of humans and arbovirus animals. This disease manifestation is called __________.
3. A_______ is a disease that can be transmitted from animals to humans.
4 Several encephalopathies, such as Eastern equine encephalitis and West Nile virus encephalitis, are caused by the____________ These viruses can infect humans and and animals such as horses and birds.
Answer:
the correct option is:
A virus that can be transmitted through arthropods such as ticks, flies, and mosquitoes is considered an arbovirus.
2. Some arboviruses can move through the bloodstream and infect the brains of human and animal arboviruses. This manifestation of the disease is called encephalitis.
Explanation:
Arboviruses are very dangerous for humans, some do not generate painful bites, others are hematofogous (they feed on human blood) and others are nocturnal, which bite humans at night without their perceiving it.
Diseases of these viruses that are transmitted by vectors such as arthropods cause encephalitis, cardiac, pulmonary disorders, etc.
An example of this is the Chagas disease that is generated by the transmission of the Vinchuca arthropod.
what doesnt occur in translation
Answer:
the sequences of nucleotides on the TRNA is read in triplet's called codons is not a key in the process of translation.
1. Why did you use a pencil to mark the paper and not a pen? 2. Why do you have to use a different capillary tube for each sample? 3. Why is it very important in the amino acid chromatogram not to touch the paper with your fingers or hands? 4. If two samples have identical Rf values does this mean that they are necessarily identical molecules? Explain 5. What is your unknown? How do you know?
Answer:
a pencil can be erased if mistakes happenn/agerms can spreadExplain how respiration occurs in plants. Someone please answer
Answer:
Respiration is the process includes plants,receive their energy for a chemical chain system is called respiration.
Explanation:
Respiration is the biochemical process , is the external environment the cell,special living a tissues.
Respiration is the process plants oxygen gas inhaled and the carbon gas exhaled out the plants.
During the respiration is the gas exchange process different parts of the plants:-ROOTS, STEMS, plants exchange respiration easily.
Roots are the underground part of the plant and present in the soil particles, and the night the respiration plants is prominent.
Respiration in stems air the diffused the various parts of the cell for passes respiration.
Leaves is the process that pores referred as exchange of gas and the leaves.
In 1998, paleoanthropologist Rick Potts published an article in The Yearbook of Physical Anthropology, a peer-reviewed journal. The article was titled “Environmental Hypotheses of Hominin Evolution.” In his paper, Potts claimed that great variations in environmental conditions over time were responsible for the adaptability of humans and the success of our species. Which would most likely be found in his paper? a review of modern human anatomical structure evidence of changing environmental conditions, with references the reasons competing hypotheses are wrong his opinion of what will happen to the survival of the human race
Answer:
Dr. Potts used environmental data to support environmental hypotheses capable of explaining human evolution
Explanation:
In this paper, the author stated that environmental factors have been fundamental for the emergence of adaptive traits during human evolution. In consequence, Dr. Potts explained how particular environmental factors and habitats might have shaped human evolution. For example, it has been hypothesized that dry savanna vegetation might have been a key environmental factor associated to the emergence of human traits including, among others, bipedality, making of tools from stones, the development of human brains, etc. In order to prove this hypothesis, the author recorded environmental data from different regions in Africa (Olorgesailie, Olduvai, Turkana, Zhoukoudian, etc), where it is believed that first hominids evolved about 6-8 million years ago.
ITS NOT B AND ITS NOT C
SOOO EITHER D OR A
Explanation
Which glial cells support neurons metabolically
Endothermic animals maintain their body temperature by increasing metabolic heat production in cool environments. Which food chain loses the most energy to cellular metabolism? algae → mosquito → spider → bat algae → mosquito → bat algae → mosquito → spider → snake algae → mosquito → bat → weasel
Organisms use carbohydrates to build large molecules. Some carbohydrates act as energy stores, and others give structural support. Carbohydrates are also broken down to generate metabolic energy.
Match the three specific examples of carbohydrate use below to a general function.
A liver cell synthesizes glycogen from glucose.
A plant cell synthesizes cellulose from glucose.
A brain cell uses the energy in glucose to synthesize ATP.
Answer:
"A liver cell synthesizes glycogen from glucose." ---> build large molecules.
"A plant cell synthesizes cellulose from glucose." ---> structural support.
"A brain cell uses the energy in glucose to synthesize ATP" obtaining energy or reserve energy.
Explanation:
Carbohydrates are classified into large groups, where the simplest are monosaccharides (ex: glucose), followed by desacarids, trisaccharides and polysaccharides as the most complex.
Carbohydrates are hydrated carbonic structures that also attract water masses, they are very useful when it comes to generating energy reserves, energy sources, structures of tissue or vegetable support, and together with proteins are one of the most fundamental components of extracellular matrices to nourish various cells, such as proteonglycans or glycoproteins.
A mosquito somatic cell contains 6 chromosomes. This means that ____ different combinations of chromosomes are possible in the mosquito’s gametes as a result of the random alignment of chromosomes during meiosis.
Answer:
8
Explanation:
The law of independent assortment of genes as proposed by Gregor Mendel states that the alleles of a gene will separate into gametes independently of the alleles of another. This means that during the metaphase stage of meiosis I, line up randomly at the metaphase plate of the cell in order to be separated independently.
According to the question, a mosquito has 6 chromosomes in its somatic cells. This means that 2n (diploid) = 6 Chromosomes. Hence, after meiosis, its gametes (n) will contain 3 chromosomes each. To find the number of different combinations of chromosomes possible in the mosquito’s gametes, we use 2^n where n represents the number of haploid chromosomes.
Hence, if 3 chromosomes are possible in a mosquito's gametes, 2^3 = 8 different combinations of chromosomes are possible in the gametes as a result of random orientation during the metaphase of meiosis.
If a forest contained most light-colored trees, which type of moth would you expect to be most common
Answer:
Light colored moths(Peppered moths)
Explanation:
Because they can blend in to their enviornment and not get eaten by predators
Answer:
light colored moths
Explanation:
because they can blend into their environment
Nonvascular plants lack _____. a. zygotes b. gametes c. seeds d. spores e. chloroplasts
Answer: Nonvascular plants lack seeds
The Non vascular plants lack seeds as there is no seed found in the non vascular plants. Thus, option C is correct.
What is the example of Non vascular plants?
The example of Non vascular plants is Ferns which has been refer to the vascular plants which usually reproduce via spores and they neither have seeds nor they have flowers as well as they also show alternate of generation in which diploid sporophyte is a dominant phase of the life.
The diploid sporophyte produces spores through meiosis and the spores divide through mitotic divisions and get developed into haploid gametophytes. The gametophyte produces haploid gametes which fertilize to produce a diploid zygote. The zygote develops and grows into mature sporophyte through mitotic divisions.
Therefore, The Non vascular plants lack seeds as there is no seed found in the non vascular plants. Thus, option C is correct.
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Without doing any further work, comment on what conclusions you could draw if you conducted a test of the null hypothesis that the mean number of bacteria is the same at the source and at the outlet, versus the two-sided alternative.
Answer:
The null hypothesis is incorrect.
Explanation:
The null hypothesis is incorrect because the average number of bacteria did not remain the same at the source and at the outlet. We know that bacteria reproduce in a very less time and they use reproduction methods such as binary and multiple fission so with the passage of time, the population of bacteria increases and did not remain the same at the source and at the outlet.
A pharmaceutical company is working on a drug to slow the spread of Ebola. Which of the following should be the company's focus?
a. Sanitizing the drinking water
b. Protecting the food supply
c. Person-to-person contact
d. Killing the insect vector
Answer:
C
Explanation:
Although Ebola isn't transferred by the air and through touch. Bodily fluids like sweat, saliva, urine, breastmilk, semen, and vomit all transmit the disease, if a person gets it in a cut or is directly introduced by it (sexual intercourse.)
In the microarray analysis some genes, such as ERB-B2 and ESR1, have been found to be associated with particular disease or conditions such as cancer. Other genes, such as the ABC-B2 gene, are not associated with a disease but are involved in resistance to certain drugs or treatments. Why would it be useful to test for the expression of genes like the ABC-B2 gene on the microarray
Answer:
The expression of genes associated with drug resistance leads to the reduction in the effectiveness of drugs against cancer cells.
Explanation:
In cancer, drug resistance is produced when oncogenic cells are able to develop mechanisms of resistance against drugs such as, for example, chemotherapeutic agents. In these cases, therapeutic treatments become ineffective to fight against cancer cells and tumor progression. In consequence, it is imperative to trace the expression of target oncogenes associated with drug resistance in order to provide effective treatments to eliminate cancer cells.
42) When yellow-seeded and green-seeded pea plants are crossed, all the offspring are yellow-seeded. When the F1 yellow-seeded plants are crossed to green-seeded plants, what is the hypothesized genetic ratio
Answer:
See the answer below
Explanation:
From the illustration, the yellow color trait is dominant over the green trait.
Assuming that yellow seededness is represented by the allele Y and green seededness by the alleles y. Y is dominant over y, hence a yellow seeded plant would be either YY or Yy while a green seeded plant would be yy.
For a cross between a yellow seeded plant and a green seeded plant to yield all yellow seeded offspring, it means that the parents are YY and yy.
(yellow)YY x (green) yy
F1 progeny: All Yy (yellow)
Now, Yy is crossed with green-seeded plant, yy.
Yy x yy
Yy Yy yy yy
Hypothesized Genotypic ratio
Yy = 1/2
yy = 1/2
Hypothesized Phenotypic ratio
Yellow seeded = 1/2
green seeded = 1/2
Is cloning an organism the same as cloning a gene
Answer:no. In nature, some plants and single-celled organisms, such as bacteria, produce genetically identical offspring through a process called asexual reproduction. In asexual reproduction, a new individual is generated from a copy of a single cell from the parent organism.
Natural clones, also known as identical twins, occur in humans and other mammals. These twins are produced when a fertilized egg splits, creating two or more embryos that carry almost identical DNA. Identical twins have nearly the same genetic makeup as each other, but they are genetically different from either parent
Gene cloning produces copies of genes or segments of DNA. Reproductive cloning produces copies of whole animals. Therapeutic cloning produces embryonic stem cells for experiments aimed at creating tissues to replace injured or diseased tissues.
Gene cloning, also known as DNA cloning, is a very different process from reproductive and therapeutic cloning. Reproductive and therapeutic cloning share many of the same techniques, but are done for different purposes.
Explanation:
Which of the following practices that are needed to run a nuclear power plant has a negative impact on both air and water
Answer:
The options are
a.cooling of the power plant
b.mining of uranium
c.storage of radioactive waste
d.monitoring the reactor
The answer is b.mining of uranium
Explanation:
Uranium is known as a radioactive element which is used as a fuel to power a nuclear energy plant. Mining of uranium could cause it to mix with air and water which results in contamination.
When contamination occurs and it gets into the body of humans or animals by inhalation or ingestion it poses a high risk of cancer and kidney damage.
The mitochondrion, like the nucleus, has two or more membrane layers. How is the innermost of these layers different from that of the nucleus?
Answer:
The double membrane of the mitochondria is highly folded,and therefore wider when unfolded than that of the nucleus.This is an adaptive feature to increase the surface area for reactions (electrochemical gradient) by accommodating protons pumped into it by the proton motive force(PMF) from the matrix to set up the electrochemical gradients needed to generate the energy needed by ATPase synthase enzymes for ATPs synthesis.
Required number of protons needed to be accommodated by the double membrane to generate enough energy for ATPase synthesis,therefore larger surface area is needed.
Explanation:
Mitochondria is the powerhouse of the cell, which is a membrane-bound organelle found in the eukaryotic cell. The inner layer of the mitochondria has cristae, which is absent in the outer layer.
Mitochondria is a membrane-bound organelle, which is composed of outer and inner layers.
The inner layer has cristae or folds, which increases the surface area for an electrochemical gradient.
The cristae are separated by cristae junctions, which are juxtaposed to the outer layer of the mitochondria.
The inner layer helps in electron transport and ATP synthesis. The membrane is surrounded by the mitochondrial matrix, which helps in the transportation of protein complexes during the citric acid cycle.
Therefore, the inner membrane of mitochondria has cristae whereas, the outer layer lacks the folds.
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A plant is a
A one-celled eukaryote
B one-celled prokaryote
C multicellular eukaryote
D multicellular prokaryote
the answer should be c hope this helps:)
Answer: A plant is a multicellular eukaryote
Explanation:
Animals plants, fungi and protists are eukaryote. All multicellular organism are eukaryote. Eukaryotes may also be single-celled.
Larry recalls his first memory of riding a red tricycle at the age of 4. Larry’s memory is: True False
Answer:
True
Explanation:
False memory refers to remembering an event differently from the way it happened or remembering events that never happened at all.
Larry's memory is a true memory because it doesn't sound like something that could be made up. Also, most children ride tricycles around the age of 4 or even younger.
Hope that helps.