Answer:
sedimentary rocks
Explanation:
How are sedimentary rocks formed? Forms from when sediments are deposited, buried, compacted & cemented together.
The sedimentary rocks are made up of particles whose size is about 0.05cm.
What are sedimentary rocks?Sedimentary rocks are the type of rocks which are formed by the accumulation or deposition of mineral or organic particles at the surface of Earth, followed by cementation of the deposit. Sedimentation is the collective term used for the processes which cause these particles to settle in place.
The sedimentary rock pebbles size ranges from 0.2 centimeters in diameter to up to 6.4 centimeters in diameter. Cobbles are the second-largest sediment size and it ranges from 6.4 centimeters in diameter to up to 25.6 centimeters.
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in human cells 2N = 46. how many chromosomes would you expect to find in a sperm cell? in am egg cell? in a white blood cell? Explain
Answer:
There will be 23 chromosomes in a sperm cell, 23 chromosomes in an egg cell, and 46 chromosomes in a white blood cell
Explanation:
Human cells are diploid in number i.e they exists in two basic sets (2N =46, where N is 23). So, cells of human body such as blood cells like white blood cells have two basic sets of chromosomes i.e 46 chromosomes, since they are produced by mitosis.
On the other hand, cells of humans involved in sexual reproduction such as the gametes (sperm and egg) have only one set of chromosomes since they are produced by meiosis - so they are haploid (N =23).
Answer:
Sperm=23
Egg cell=23
White blood cell=46
Explanation:
During cell division Meiosis produce haploid number of gametic chromosome 23.
The somatic cell contains 46 chromosome i.e diploid chromosome number. During cell division in meiosis gametes cells contains haploid number-23 chromosome which is half of the somatic cell chromosome.
During conjugation, haploid chromosome is donated by each parent to give a diploid organism with 46 chromosome number.
White blood cell contains 46 chromosome because it doesn't undergo cell division it is a somatic cell.
Which event describes a change where evolution has happened? An allele frequency changes in a population. A white-eyed fly is born into a population of brown-eyed flies. A species of tree dies out. A school of fish moves to a new environment.
Answer:
A white-eyed fly is born into a population of brown-eyed flies.
Explanation:
In the example, a new mutation (i.e., white-eyes) has appeared in the progeny. In the case that this new mutation has adaptive value, it will be transmitted across generations and therefore will increase its frequency in the population
The event that describes a change where evolution has happened is when an allele frequency changes in a population. This is based on the genetic definition of evolution, which involves shifts in allele percentages over time in a population.
Explanation:Defining Evolution through Allele FrequenciesEvolution in biology refers to a change in the characteristics of a population over time, which at its core, involves a change in genetic material. Allele frequencies are the percentages of different versions of a gene in a population. A change in these frequencies is evidence that evolution is occurring. This can happen due to various factors, such as natural selection, mutation, genetic drift, gene flow, and nonrandom mating.
An example of an event that describes a change where evolution has happened is when an allele frequency changes in a population. This mirrors the genetic definition of evolution and aligns with the understanding established by the Hardy-Weinberg Theorem. For instance, using the ABO blood system, if the frequency of one allele changes over time, this represents an evolutionary change in that population.
However, a single white-eyed fly being born into a population of brown-eyed flies does not constitute evolution, since evolution refers to changes across the population, not individuals. Similarly, the extinction of a species or the migration of a school of fish might result from evolution but are not themselves examples of evolution happening.
From an evolutionary point of view, what important process occurs when a young male baboon leaves the troop that he was born in to join another troop?
Answer: GENE FLOW
From an evolutionary point of view, what important process occurs when a young male baboon leaves the troop that he was born in to join another troop?......GENE FLOW.
Explanation: Gene flow is also called MIGRATION. It's simply the transfer of gene/genetic materials from one population to another.
It can also be referred to as the movement of an individual or animal from one popularity to another.
Example; Pollination which involves a bee or butterfly catering pollen grain from the anther of a flower to the stigma of another flower, in essence moving the pollen grain from one population to another population
A medical study was investigating if getting a flu shot actually reduced the risk of developing the flu. A hypothesis test is performed. Which of the following will result in a Type I error?
a. Researchers said the flu shot reduced the risk of developing the flu when it actually did
b. Researchers said the flu shot did not reduce the risk of developing the flu when it actually did.
c. Researchers said the flu shot did not reduce the risk of developing the flu when it actually didn't
d. Researchers said the flu shot reduced the risk of developing the flu when it actually didn't.
e. Researchers could not tell if the flu shot reduced the risk of developing the flu because of other problems with the study.
Answer:
d. Researchers said the flu shot reduced the risk of developing the flu when it actually didn't.
Explanation: The rejection of true null hypothesis based on experimental procedures is called Type 1 error.
The primary aim of the investigation was to find out if a flu shot guide against flu infection or not.Therefore to arrive at a conclusion, this true null hypothesis must be tested, and evidences of the effects of flu shot on development of flu could be determined.
Therefore after testing;evidences arrive at will determine if flu shot reduces the risk or no effect at all.However, if there is no significant evidence to support the potency of flu shot, and it was jumped to conclusion that its actually reduces the risk of development,(that is null hypothesis was rejected) then the basis for the test- which is to test the null hypothesis has been defeated, thus Type 1 error has been committed .
When the researcher concluded that flu shot actually reduced the risk,when actually it was the contrary, he had rejected the objective of the true null hypothesis .Besides there was no probability value to show that this was below 0.05 confidence value.
A Type I error occurs when researchers incorrectly reject the null hypothesis and claim that the flu shot reduced the risk of developing the flu when it actually didn't.
option a is correct
Explanation:The correct answer is a. Researchers said the flu shot reduced the risk of developing the flu when it actually did. A Type I error occurs when the null hypothesis is rejected, even though it is true.
In this case, the null hypothesis would be that the flu shot does not reduce the risk of developing the flu, but the researchers incorrectly rejected this hypothesis and claimed that it did reduce the risk.
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Scientists commonly choose white blood cells that are going through mitosis to prepare karyotypes. Why?
Answer:
This is because during the phase of mitosis, chromosomes of the white blood cells condense.
Explanation:
A karotype tells us about the appearance of a chromosome which involves the number of the chromosomes as well as the structure of the chromosomes.
Karotype can be used to detect any defect or abnormalities that can lead to sicknesses or health disorders in a person.
In order to prepare a karotype, white blood cells going through mitosis is used because during mitosis the chromosomes of the white blood cells condense thereby making movement easier for the cells.
Answer:
This is because during mitosis, chromosomes are more condensed than during interphase.
Explanation:
During interphase, the cell grows and the nuclear DNA is duplicated. Interphase is followed by the mitotic phase, individual chromosomes are not visible, and the chromatin appears diffuse and unorganized
During the mitotic phase, the duplicated chromosomes are segregated and distributed into daughter nuclei. The cytoplasm is usually divided as well, resulting in two daughter cells.
The cichlid Cynotilapia afra, introduced at West Thumbi Island in Lake Malawi in the 1960s, has split into two genetically distinct populations, located at the north and south ends of the island. How can scientists determine whether these populations are now different species, according to the biological species concept?
Explanation:
Determine whether peoples from one populace will interbreed with people from the other populace when brought into one another's local environmentsAn animal category is a gathering of individual living beings that interbreed and produce fruitful, practical posterity. As indicated by this definition, one species is recognized from another when, in nature, it isn't feasible for matings between people from every specie to create prolific posterity Individuals from similar species share both outer and inward qualities that create from their DNA. The closer relationship two living beings share, the more DNA they share for all intents and purpose, much the same as individuals and their families. Individuals' DNA is probably going to be more similar to their father's or mother's DNA than their cousin's or grandparent's DNA. Living beings of similar species have the most significant level of DNA arrangement and, subsequently, share attributes and practices that lead to effective propagationWhat is not a desirable blood lipid value
Answer:
When the Total cholesterol level is 240 mg/dL and above
Explanation:
Lipids in our body is classified as LDL-cholesterol, HDL- cholesterol and triglyceride. The human body lipidi content is measured as lipid profile that is the total cholesterol level, LDL-cholesterol, HDL- cholesterol and triglyceride.The lipid value in our body is said to be non desirable when the Total cholesterol level is 240 mg/dL and above, LDL cholesterol is 190 mg/dL and above, HDL cholesterol is 60 mg/dL and above, and when the triglycerides level is 500 mg/dL and above
An undesirable blood lipid value is a high low-density lipoprotein (LDL) level above 160 mg/dL or a high triglyceride level above 150 mg/dL, both of which increase the risk for heart disease and stroke.
Explanation:Not all blood lipid values are equally beneficial for health. A desirable blood lipid value is one that reduces the risk of cardiovascular disease. High-density lipoprotein (HDL), often called the 'good cholesterol transporter,' is one such lipid profile component that is desirable to have in high amounts. HDL helps transport cholesterol from the tissues back to the liver, where it can be excreted, thus lowering the risk of heart disease. The desirable level for HDL is above 40 mg/dL for men and above 50 mg/dL for women.
In contrast, low-density lipoprotein (LDL), known as the 'bad cholesterol transporter,' is a lipid profile component that is not desirable when found at high levels. Elevated levels of LDL are associated with an increased risk of atherosclerosis and heart attack. An ideal LDL level is less than 100 mg/dL, while an LDL level above 160 mg/dL is considered high and not desirable.
Furthermore, although not cholesterol, triglycerides are another type of fat in the blood that can pose health risks when high. A normal triglyceride level is 150 mg/dL or lower, and higher levels have been linked to an increased risk of atherosclerosis, heart disease, and stroke. Hence, an undesirable blood lipid value would be a high LDL cholesterol or a high triglyceride level.
The fact that infection by Bd causes lethargy in many infected amphibians can have what effect on efforts to accurately census the numbers of dead or dying amphibians at a particular time, in a particular habitat?
Explanation:
Two of the above statements are plausible
For several decades now, amphibian species worldwide have been in decline. A significant proportion of the decline seems to be due to the spread of the chytrid fungus, Batrachochytrium dendrobatidis (Bd). Chytrid sporangia reside within the epidermal cells of infected animals, animals that consequently show areas of sloughed skin. They can also be lethargic, which is expressed through failure to hide and failure to flee. The infection cycle typically takes four to five days, at the end of which zoospores are released from sporangia into the environment. In some amphibian species, mortality rates approach 100%; other species seem able to survive the infection.
20. Which nutritional classification would you predict to fit most of the well-known members of the human microbiome? A. Photolithoautotrophs B. Chemoorganoheterotrophs C. Chemolithoautotrophs D. Chemolithohetertrophs
Final answer:
The nutritional classification fitting most well-known members of the human microbiome is Chemoorganoheterotrophs, as these organisms utilize organic molecules as both carbon and electron sources.
Explanation:
The nutritional classification that would fit most of the well-known members of the human microbiome is B. Chemoorganoheterotrophs. These organisms are distinguished by their ability to use organic molecules as both their carbon and electron sources. The human microbiome, comprising various bacteria, fungi, and archaea, relies extensively on the organic compounds sourced from the human body itself. Unlike autotrophs that can synthesize their own food from inorganic substances, chemoorganoheterotrophs obtain their energy from the oxidation of organic compounds. This category includes a vast majority of bacteria and all fungi which are essential members of the human microbiome, playing crucial roles in digestion, synthesis of vitamins, and protection against pathogenic invaders.
The greater the mass of tissue in an organ, the greater its need for an adequate blood supply. Which chamber of the heart has the highest probability of being the site of a myocardial infarction?
Left ventricle.
Explanation:
Left ventricle is the chamber of the heart that has to work against the highest resistance. Because it has to pump blood into the systemic circulation. moreover it has a greater muscle mass and is more thicker than the right chambers of the heart.
Thus, the oxygen demand of left ventricle is much more than that of the other three chambers. If by any means the blood supply to the heart is not sufficient to fulfill the oxygen demand of the left ventricular cells then it would result in myocardial infarction commonly termed as heart attack
Which of the following correctly pairs an enzyme with its action? Group of answer choices a. RNA polymerase: b. binds to origin to signal the start of replication telomerase: c. aids in editing of mRNA DNA polymerase: d. pairs DNA nucleotides with RNA nucleotides aminoacyl-tRNA synthase: e. joins amino acid to tRNA
Answer:
D
Explanation:
The DNA sequence binds to the RNA sequence during transcription. This reaction is catalyzed by the enzyme RNA polymerase, therefore coping the DNA information into the messenger RNA (mRNA).
RNA polymerase binds to origin to signal the start of replication, telomerase aids in editing of mRNA, and DNA polymerase pairs DNA nucleotides with RNA nucleotides.
Explanation:The correct pairing of an enzyme with its action is:
a. RNA polymerase: binds to origin to signal the start of replicationb. telomerase: aids in editing of mRNAc. DNA polymerase: pairs DNA nucleotides with RNA nucleotidesd. aminoacyl-tRNA synthase: joins amino acid to tRNARNA polymerase is responsible for initiating transcription by binding to the promoter region and signaling the start of replication. Telomerase is involved in the editing of mRNA. DNA polymerase pairs DNA nucleotides with RNA nucleotides during DNA replication. Aminoacyl-tRNA synthase joins amino acids to tRNA molecules. These enzyme-action pairings are all accurate.
The rotator cuff tendons enclose the shoulder joint on all sides except _______________
Answer:
The subscapular.
Explanation:
The,subscapular is located between the subscapularis tendon and the scapula. It reduces wear and tear on the tendon during movement at the shoulder joint.
Feigen baum popularized the term _____, which described the portion of plant capacity wasted due to poor quality. 1. Exponential distribution 2. Hidden factory 3. Quincunx 4. Quality trilogy 5. Out sourcing
Answer:
2. Hidden Factory
Other biologists of Darwin's time had proposed that living things had changed over time. Which feature distinguished Darwin's theory of evolution from the proposals of the other biologists?
Final answer:
Darwin's theory of evolution was distinguished from others by the concept of natural selection, where advantageous traits are passed on and lead to species evolution, a concept supported by his observations and later by genetics.
Explanation:
The feature that distinguished Charles Darwin's theory of evolution from the proposals of other biologists of his time was the concept of natural selection. While other scientists, such as Jean-Baptiste Lamarck, had suggested that species change over time, Darwin proposed that this change was due to the differential survival and reproduction of organisms with beneficial traits, which he termed natural selection. It was through natural selection that advantageous characteristics were passed down through generations, leading to the evolution of species.
Darwin's ideas were supported by his observations during the voyage of the HMS Beagle, particularly in the Galápagos Islands, where he saw unique species adaptations. His comprehensive explanation for the mechanism behind evolution was unprecedented and became a cornerstone of biology. Darwin's understanding of evolution by natural selection was further solidified with the understanding of genetics and the role of genes in heredity.
If the frequency of a particular allele that is present in a small, isolated population of alpine plants decreases due to a landslide that leaves an even smaller remnant of surviving plants bearing this allele, then what has occurred? A. A bottleneck B. Genetic drift C. Microevolution D. A and B only E. A, B, and C are all correct.
Answer:
E. A, B, and C are all correct.
Explanation:
Microevolution is an evolutionary change that is said to occur on a small scale within a population of species over a short period of time. This can be seen in the case of the population of alpine plants. The change is within the population.
Genetic drift, by definition is the change in the allele frequencies, as can be seen in the alpine plants, which is brought about by a bottleneck effect. In order words, bottleneck effect occurs when a population size is reduced drastically as a result of environmental events such as landslide, that can be seen in the case of alpine plants. This genetic drift example randomly selects the surviving individuals in this microevolution.
At the time when the frequency of the specific allele should be present so here the bottleneck, genetic drift, and the microevolution should be considered. Hence, option E is correct.
What it should be occured?In the bottleneck effect, the frequency of the population should be changed because of the specific event like as a natural calamity. In genetic drift, frequency changed owing to the disappearance of the genes. And, In microevolution, the changes occur because of genetic drift, selection, gene flow and mutation.
Therefore, the option E is correct.
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If a uniform becomes saturated with blood, what is the proper action that should be taken for the athlete to continue participation? A. The uniform should be changed at halftime B. The uniform should be changed immediately C. No action should be taken and the athlete continues without interruption D. The blood should be rinsed off with water
Explanation:
(B) The uniform should be changed immediately
The uniform ought to be changed right immediately. Blood is perilous as it could convey pathogens from tainted individuals. Uniform to control seeping by a player yet were adjusted to "a reasonable amount of time" to Cleanup time for blood spills and trade of "saturated uniforms" is at the circumspection of the arbitrator. The bone marrow produces undeveloped cells, the structure obstructs that the body uses to make the distinctive platelets red cells, white cells and platelets.Imagine a gene in which the sequence that is transcribed into a GAG codon, which codes for glutamic acid, is mutated to GUG, which codes for valine. What type of mutation is this
Answer:
missense
Explanation:
Here is the complete question:. Imagine a gene in which the sequence that is transcribed into a GAG codon, which codes for glutamic acid, is mutated to GUG, which codes for valine. What type of mutation is this?
- nonsense
- frameshift
- missense
- silent
- base pair deletion.
a missense mutation is a point mutation in which a single nucleotide change results in a codon that codes for a different amino acid. It is a type of nonsynonymous substitution.
During the spring and fall each year thousands of maple trees are tapped for their fluids in order to make "real" maple syrup. If you were to tap into a maple tree to extract the syrup (sucrose) which tissue layer do you want to tap into
Answer:
The phloem tissue layer
Explanation:
The phloem tissue of a plant is one of the vascular tissues of higher plants responsible for the conduction or transportation of photo-synthetically manufactured food (usually in the form of sugar) round the body of the plant to the various tissues and organs that require it.
The tissue moves food materials from their source of manufacture, usually the leaf, to other parts of the plant. Hence, in order to extract the syrup from the maple tree, the phloem layer must be tapped into.
A twin study is conducted to examine the role of genetics and environment on the fondness of individuals for chocolate. Which of the following results would lead to the conclusion that genetic factors are important in the development of this trait?
a. Twins who have lived together are more similar on the trait than twins who have lived apart.
b. Twins who have lived apart are more similar on the trait than twins who have lived together.
c. Identical twins are more similar on the trait than fraternal twins.
d. Fraternal twins are more similar on the trait than identical twins
c. Identical twins are more similar on the trait than fraternal twins.
Explanation:
Twins are siblings from same pregnancy.Identical twins are monozygotic i.e they develop from the same zygote.Fraternal twins are dizygotic i.e. they develop from two different zygote formed by fusion of of two different eggs with two different sperms.Thus,identical twins genetically identical to each other but fraternal twins are not.So if identical twins are more similar in a given trait than fraternal twins then it can be concluded that the trait is dependent on Genetic factor.A student uses a string to model four pairs of homologous chromosomes in a parent cells. Each Chromosome pair is a different color. Which model would best show the genetic genetic makeup of a daughter cell produced by meiosis?
A) two strings, each combination of different colors.
B) Two Strings, each same color.
C) Four Strings, each a combination of different colors.
D) Four Strings, each the same color
Explanation:
All in all, this procedure includes a "parent" cell parting into at least two "little girl" cells. Right now, parent cell can give its hereditary material from age to age. Meiosis, then again, is a particular type of cell division that happens in living beings that imitate explicitly. As referenced above, it produces regenerative cells, for example, sperm cells, egg cells, and spores in plants and parasites. In people, extraordinary cells called germ cells experience meiosis and at last offer ascent to sperm or eggs. Germ cells contain a total arrangement of 46 chromosomes (23 maternal chromosomes and 23 fatherly chromosomes). Before the finish of meiosis, the subsequent regenerative cells, or gametes, each have 23 hereditarily one of a kind chromosomes.Hence, the right answer is option C "four strings, each a combination of different colors"
Humans are much more likely to associate snakes with danger than flowers and danger. According to the evolutionary perspective, this tendency is called __________.
Answer:
preparedness.
Preparedness is the tendency to learn some associations more easily, quickly and permanently than others.
Answer: PREPAREDNESS
Humans are much more likely to associate snakes with danger than flowers and danger. According to the evolutionary perspective, this tendency is called PREPAREDNESS.
Explanation: Preparedness is that tendency that people fear things that are harmful quickly and effortlessly more than things that are not harmful example; people are more likely to fear a scorpion than a tree.In essence, people learn some association more quickly,easily and permanently than others.
Examine the model of the secretion of a protein into the environment surrounding a cell. Identify and organize the organelles involved in the process, from protein synthesis through secretion. A) Golgi apparatus, vesicle, cell membrane B) mitochondria, ER, lysosome, cell membrane C) ribosome, Golgi apparatus, lysosome, cell membrane D) ribosome, ER, Golgi apparatus, vesicle, cell membrane
Answer:
D) Ribosome, ER, Golgi apparatus, vesicle, cell membrane.
Explanation:
Ribosomes are mostly found on the memranes of the rough endoplasmic reticulum of cells. They have ribonucleic acid molecules and are responsible for the synthesis of proteins within the cell.
The endoplasmic reticulum is a membranous network distributed within the cell and is responsible for the transport of the proteins synthesized by the ribosomes.
The Golgi apparatus transport synthesized products to be secrete at the cell membranes. Glycoproteins are also manufactured at in the Golgi apparatus.
The vesicles act as storages in which these products are kept and it open up at the cell membrane to release them to the surroundings.
Answer:
D) ribosome, ER, Golgi apparatus, vesicle, cell membrane
Explanation:
This is the sequence of the pathways for the process of gene expression for protein synthesis.
It begins in the Ribosomes with the process of translation of the transcribed mRNA, to synthesise a polypeptide chain of Amino acids. These are passed into the rough- ER lumen or membrane.where they are modified; checked if the protein is well folded, and sugar molecules are also added . They are later packed in small coated vesicles en route the Golgi complex.
They are moved by cisternae migration by this vessicle, which are micro-tubules which makes use of cell cytoskeleton to navigate and move through the cytoplasm to trans-golgi ,,where they are sorted out .Some sugar molecules are removed while new are added. They are later transported to the trans-golgi network/ apparatus; for packaging to secretory vesicles and transport vesicles. The latter fused with the plasma membrane , and secreted to the outside by Exocytosis as uncoated protein.
To calculate the turnover number of an enzyme, you need to know: A) the enzyme concentration. B) the initial velocity of the catalyzed reaction at [S] >> Km. C) the initial velocity of the catalyzed reaction at low [S]. D) the Km for the substrate. E) both A and B.
Explanation:
Enzymes belong to the proteins category because enzymes are long chains of amino acids bound together by peptide bonds Enzymes have a special marker on them called an active site that, like a puzzle piece, fits with only one other type of molecule, generally referred to as a substrate. The substrate is a molecule that will undergo a reaction that results in it splitting into two separate molecules, called productsThe substrate-specific to a particular enzyme will bind at the active site, forming what is known as an enzyme/substrate complex. In other words, a complex formed by the union of the enzyme and substrateHence, the right answer is option E "both A and B"To calculate the turnover number of an enzyme, you need to know: E) both A and B.
Turnover numberTurnover number is defined as chemical reactions of an enzyme concentration with substrate molecules at per second. Turnover number is calculated by a simple formula
[tex]k_{cat}= \frac{V_{max}}{E_t }[/tex]
Where Vmax is the rate of reaction at saturation point and Et is the enzyme concentration.
Thus, the enzyme concentration and the initial velocity of the catalyzed reaction at [S] that is represented by km
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A dendritic or langerhans cell is a specialized ________.
A dendritic cell is an immune cell that processes antigen material and presents it on the surface of other cells to induce an immune response.
Explanation:A dendritic cell is an immune cell that processes antigen material and presents it on the surface of other cells to induce an immune response. It is a specialized type of immune cell that functions as a macrophage and is found in the stratum spinosum of the skin.
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Eubacteria are classified by BLANK
Answer:
Eubacteria are classified by their morphology into cocci, bacilli and helical bacteria.
Explanation:
Eubacteria, or true bacteria, are a group of unicellular prokaryotic organisms, characterized by a lack of true nucleus and most organelles. Their genetic material is found in the cytoplasm and they have been associated with disease production in other organisms.
According to their morphology, eubacteria are classified as
Cocci, either round or oval in shape.Bacilli, elongated in shape, similar to small sticks.Spirils, including vibrios and spirochetes.Additionally, bacteria can be equipped with mobile appendages, such as cilia and flagella.
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Differences between Eubacteria and Archaea https://brainly.com/question/1698130
Answer:
their shape
Explanation:
Which of the following is TRUE? Species on Earth today are just a fraction of all species that ever lived. The number of species existing at one time has decreased throughout history. Until recent history, extinctions have always happened gradually and on a small scale. Most organisms present early in Earth's prehistory were more complex than modern organisms. Natural selection always favors complexity and a larger body size
Answer:
Until recent history,extinctions have always happened gradually and on a small scale.
Explanation:
Extinction occur when environmental factors like natural disaster,habitat fragmentation,over exploitation,global change don't favor the survival of species thus gradually leads to extinction of species.
Some times human activity becomes the major problem for extinction.More over,poor reproduction,decline in population number and genetic inbreeding also leads to extinction.
99% of all species that exist on earth become disappeared.
Evolution leas to speciation which leas to formation of new species but species become extinct when they are unable to survive against competition.
Species on Earth today are just a fraction of all species that ever lived. Throughout Earth's history, there have been numerous extinctions. An example of a mass extinction event is the Cretaceous-Paleogene extinction event.
Explanation:The statement: Species on Earth today are just a fraction of all species that ever lived is TRUE.
Throughout Earth's history, there have been numerous extinctions that have caused many species to go extinct.
An example of a mass extinction event is the Cretaceous-Paleogene extinction event, which led to the extinction of around 75% of all species on Earth, including the dinosaurs.
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Temperature-sensitive mutations are useful in understanding essential life processes. A temperature-sensitive mutant will be normal at a lower (non-restrictive) temperature; when shifted to a higher (restrictive) temperature, the mutant will reveal its mutant (and potentially deleterious) phenotype. You isolate a plant with a temperature-sensitive mutation in the water-splitting complex. You grow the plant at a non-restrictive temperature, then shift it to its restrictive temperature. The outcome you would most expect to see upon shifting temperature would be
decreased NADPH production.
increased NADPH production.
no change in NADPH production.
decreased sugar production.
no change in sugar production.
increased oxygen production.
Answer:
decreased NADPH production.
decreased sugar production.
Explanation:
The water-splitting complex is associated with PSII and serves as a donor of electrons to the reaction center of PSII. PSII loses its electrons upon trapping of sunlight. These electrons are passed finally to NADP reductase via electron transport chain and PSI. NADP reductase reduces NADP into NADPH. The NADPH formed during the light-dependent phase serves as reducing power in reactions of the Calvin cycle.
A mutation in the water-splitting complex would result in no electron supply to PSII and thereby, reduced production of NADPH. The reduced NADPH production would limit the supply of reducing power for the Calvin cycle and the sugar production would be decreased.
The outcome should be decreased NADPH production and decreased sugar production.
NADPH and sugar:The electrons should be transferred to NADP reductase by electron transport chain and PSI. Due to this, it gets reduced. The reduced NADPH production would limit the supply of reducing power with respect to the Calvin cycle and the sugar production would be decreased.
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As newly formed cells of the stratum basale are pushed to the surface, they accumulate keratin and undergo apoptosis. This process is referred to as _______.
Answer:keratinization
Explanation:the human skin covers the body of the human.it forms a barrier that helps prevent the entry of harmful microorganisms into the body.it also protects the body against ultraviolet rays and is involved in the regulation of body temperature.
The skin is made up of two layers;the epidermis and the dermis.the two layers are anchored together by the basement membrane.the epidermis contains keratinocytes ,which produces the tough protein called keratin.keratin helps to protect the skin.
The upper part of the skin contains older keratinocytes,which are constantly being removed.they are replaced by the newer cells.as the keratinocytes move upwards in the epidermis,they produce keratin and die off , completely filled with keratin.
What is this phenomenon known by neuroscientists? Peter suffers damage to his left frontal lobe and loses the ability to speak but can still understand speech. Despite the permanance of his damage, he is able to recover some of his speech due to his brains ability to take over the lost function.
A. Flexibility
B. Adaptiveness
C. Plasticity
D. Compensation
E. Homeostasis
Answer:
The correct answer is - plasticity.
Explanation:
Neuroplasticity, brain plasticity or plasticity of the brain is the ability of brain to develop of change throughout the life. In this case peter suffers damage or injury in his frontal lobe that stores learned ability.
As he lost ability of speak however still can understand the speech and he is still able to recover as brain has neuroplasticity that helps in recovering the lost function.
Thus, the correct answer is - plasticity.
If a person does not consume sufficient carbohydrates in food, the body will make glucose from _______ for a fuel source. This results in an undesirable breakdown of body tissue.
Final answer:
In the absence of sufficient carbohydrates, the body will utilize fatty acids and proteins as fuel sources, resulting in body wasting.
Explanation:
In conditions of low glucose, such as fasting, starvation, or low carbohydrate diets, glucose can be synthesized from lactate, pyruvate, glycerol, alanine, or glutamate. This process, called gluconeogenesis, is almost the reverse of glycolysis and serves to create glucose molecules for glucose-dependent organs, such as the brain, when glucose levels fall below normal.
In the absence of sufficient carbohydrates, the body will utilize alternative sources such as fatty acids and proteins as fuel sources. However, using protein for energy causes breakdown of body tissue, resulting in body wasting.
Ketone bodies are also produced from fats and can serve as a fuel source for the heart and other organs in times of prolonged starvation or low glucose levels.