what is the main problem with comparing the tree of life with the fossil record?

Answer:

The answer is the accessory nerve.

Explanation:

We have 12 pairs of cranial nerves, the accessory nerve is the XI pair. This is responsible for the innervation of the sternocleidomastoid and trapezius muscles.

The fibers of the accessory nerve originate from neurons that are located in the upper spinal cord. These fibers join together forming roots and once the nerve is constituted, it enters the skull through the great hole that is located at the base of the skull.

Then, the nerve continues its path along the inside of the skull in the direction of the jugular hole and then leaves the skull next to the glossopharyngeal nerve (IX) and the vagus (X).

Thus, the accessory nerve enters and leaves the skull again, characterized by being the only cranial nerve which has this behavior.

Answer:

The correct answer is indeed the

accessory nerve

The fibers that make up the accessory nerve enter the skull through the foramen magnum and proceed to exit the jugular foramen with cranial nerves IX and X. Due to its unusual course, the accessory nerve is the only nerve that enters and exits the skull.

Answer:

A. The extension of Mendelian genetics comprises the codominance, incomplete dominance, polygenic inheritance, multiple alleles, lethal genes, sex lined genes, gene mapping, and others.  

B. The phenomenon of incomplete dominance takes place when of both the recessive and dominant forms, no one gets expressed in the F1 generation, however, an intermediate expression is witnessed. For example, crossing red flower with the white one generates pink flowers.  

On the other hand, in codominance, both the alleles get expressed, like in the blood group AB. The association of genes results in epistasis, it changes the normal dihybrid phenotypic ratio, that is, 9: 3: 3: 1 to 12: 3: 1. The genes, which suppress the others are called epistatic, while the ones, which get suppressed are known as hypostatic.  

Answer:

Thanks to the fossil record, direct evidence of the evolution and change of species can be given over the years. The fossil record tells us the natural history of the species in the different geological ages and allows us to see the changes in the distributions of the species, extinction and diversification from comparison and measurement.

Answer:

Forests.

Explanation:

They decrease the amount of Carbon dioxide & increase the amount of Oxygen.

Answer:

I think trees aka plants would be the answer

Answer:

Option (b).

Explanation:

Carrier proteins allow the movement of the particles inside and outside the cells. Three types of porter are uniport, symport and antiport. These porters transport molecules in the different directions.

The antiporters transport two molecules at a time. These two molecules are transported in the opposite directions at the same time. The one molecule will move inside the cell and the other molecule will move outside the cell.

Thus, the correct answer is option (c).

Answer:

b. pieces of DNA is the correct answer.

Explanation:

A gene is a piece of DNA and it is present in the nucleus of all cell's

The function of the gene is to codes for a specific type of protein.

Genes convey the message that determines our characteristics

Genes are called as a functional unit of genetics.

Answer:

The correct answer is option d, that is, endocytosis.

Explanation:

A procedure in which a component gains entry within the cell without getting passed through the cell membrane is termed as endocytosis. In this process, the cell captivates the substances from the external of the cell by engulfing and combining them with its plasma membrane.  

The process is further differentiated into three distinct kinds. These are phagocytosis, pinocytosis, and receptor-mediated endocytosis.  

Answer:

Explanation:

Greenhouse effect is a natural phenomena. The solar radiations from the sun enters the earth atmosphere where some of the sun light is absorbed by the atmosphere as well as the terrestrial land. The rest energy is reflected back to the space. This helps in maintaining the balance of thermal energy on earth. Human activities like burning of fossil fuels, land clearing and agriculture are increasing the amount of greenhouse gases released into the atmosphere.  These gases are responsible for absorbing the thermal energy present in the sunlight. Hence, can be responsible for increasing the global temperature worldwide. This is called as greenhouse effect.

Answer:C. Mushrooms grow only in association with grass.

Explanation:

Hypothesis is a statement which includes proposed information for the cause of a particular process.

The mushroom colonizes in a form of circle in the grass lawn. It might be a pattern of development of these mushrooms. Supported by the mineral and nutrients they derive from the grass.

Thus C is the correct option.

Answer: B, Meiosis I

Explanation:

During meiosis I, genetic material halves, and you get 2 haploid cells (n) from a diploid cell (2n). Those divide again during meiosis II to form 4 different haploid cells.

DNA replicates during interphase and starting at meiosis I, 2n homolog chromosomes attach to form n tetrads. Those tetrads align in the cellular equator during metaphase I and then separate, moving to opposite poles during anaphase I. Each cell formed receives a copy of each chromosome and then divides in a process similar to mitosis during meiosis II.

Homologs of a pair move toward opposite poles of a dividing cell during meiosis I. This is different from mitosis, meiosis II, or fertilization, which involve different cellular processes.

The two homologs of a pair move toward opposite poles of a dividing cell during meiosis I. This event is known as anaphase I of meiosis I. In contrast, during mitosis and meiosis II, it is the sister chromatids, and not the homologs, that separate and move to the opposite poles. Fertilization, on the other hand, involves the fusion of two gametes (each from a different parent) and does not involve the separation of homologs.

https://brainly.com/question/29773280

#SPJ3

Answer:

The correct answer is option e. "pyrophosphate is converted to ATP so that luciferase is activated".

Explanation:

Pyrosequencing is a method of DNA sequencing that allows to detect the nucleotides that are being incorporated to a DNA template mediated by a polymerase. In the reaction mixture, pyrophosphate (PPi) is released as a result of nucleotide incorporation by polymerase. As pyrophosphate is released, it is converted to ATP so that luciferase is activated by the oxidation of luciferin. Luciferase is the enzyme that mediates the reaction that generates light and allows to identify the nucleotides that are being incorporated.

Answer:

Chromosomes are a microscopic thread-like structure, and it is the part of a cell that carries hereditary information in the form of genes.

Homologous chromosomes the relationship between two chromosome, consists of the same gene sequence, each derived from one parent. They consist of alleles of the same type of genes in the same loci. Homologous chromosomes pair up during the process of meiosis 1. The part of the Homologous chromosomes can be exchanged during the process of recombination. Examples of these are 22 autosomal chromosomes in humans.

Non-homologous chromosomes do not belong to the same pair, they consist of alleles of different types. Non-homologous chromosomes do not pair up during the process of meiosis 1. The part of the Non-homologous chromosomes can be exchanged during the process of translocation. Examples are X and Y chromosomes.  

Answer:

Their enzymes have high optimal temperatures.

Explanation:

Archaea is one of the domain among the three domains of life. Archaea bacteria are the bacteria that may exist in the extreme environmental condition.

Bacteria re also found at extreme temperatures conditions under the hotsprings. This is because these enzymes of this bacteria work at high optimal temperatures. Their enzymes are active at high temperature condition that makes them metabolically active.

Thus, the correct answer is option (c).

Bacteria that are active in hot springs are known as thermophiles. Their enzymes have adapted to work optimally at high temperatures which usually are considered destructive for most enzymes/bacteria.

Some bacteria are metabolically active in hot springs because of option c: their enzymes have high optimal temperatures. These bacteria, known as thermophiles, thrive in extremely hot environments that would be destructive to most life forms. Their enzymes and cellular components have uniquely evolved to function optimally at these high temperatures. Therefore, high temperatures become their standard operational conditions, in which enzymatic reactions and metabolic processes occur effectively.

https://brainly.com/question/31555397

#SPJ11

Answer:

The given statement is true.

Explanation:

The oxygen that is present in the atmosphere has two main sources:

Terrestrial Plants: As we know that the plants make use of sunlight, water, carbon dioxide and chlorophyll in a process termed as photosynthesis and make glucose and releasing oxygen into the atmosphere which is then used by animals for respiration. This is one of the major source of oxygen in the atmosphere.

Oxygen released from Oceans: In the oceans of the earth, water bodies ,seas tiny plants termed as Phytoplankton are present that are present near the surface of the water bodied that also release oxygen by photosynthesis and account for about 50% of the world's oxygen supply.

Answer:

Explanation:

Frederick Griffith performed a different experiment on bacterium streptococcus pneumonia. There are 2 strains of streptococcus i.e. virulent strain i.e. bacteria have a smooth capsule, and the avirulent strain, the bacteria have a rough capsule. Though the smooth live bacteria have virulent strain kills the mouse when it is injected into it. But the rough bacteria did not affect the mouse. When he heat-killed the smoothe bacteria and mix with the rough bacteria it kills the mouse. The single heat-killed smooth bacteria did not kill the mouse. Griffith concluded that there is some transforming principle responsible for making the avirulent bacteria into virulent and this process is called the transformation of bacteria. He failed to show which element transforms from the heat-killed bacteria to rough bacteria.  

This experiment was further proceeded by Avery, Macleod, Mccarty. They cultured large quantities of smooth pneumonia cells. The cells are harvested from the culture and heat-killed. Then the heat-killed bacterial cells are homogenized and cell extracts were treated with cell lysates separately. The cell lysates are - DNAse, RNAse, protease, trypsin, lipase.

Then he injected the cell extracts with rough bacteria and put this in Petri dish to form the bacterial colony. They observed each colony show a smooth bacterial colony except the DNAse treated cell. DNAse degrades the DNA and the smooth bacterial colony was not formed. This results, DNA is the element which transforms from the smooth bacteria to rough one and makes it virulent.

Avery and his colleagues finally show DNA is the genetic material.

Answer:

The correct answer is option d.

Explanation:

Chemical cycling illustrates the systems of concurrent circulation of elements between other states, compounds, and substances, and then return to their original state, which takes place in space, and on many objects in space comprising the Earth.  

Chemical cycling of the nutrients (inorganic) is needed to maintain the conservation of nutrients on Earth. The chemical cycling of nutrients in a natural system requires a pool for the elements, the activities done by human beings, the biotic community and its food chains, and an exchange pool from which producers extract their nutrients. All the mentioned factors are associated with affecting a chemical cycling in exception to the input of geothermal energy.  

Answer:

In humans, males sex determination is trigged by a Y linked gene (SYR) female sex determination occurs in XX embryos by default

Explanation:

The sex of the individual is defined through the interaction of genes that are situated in homologous pairs, that is, sex chromosomes (heterosomes or allosomes).

In humans, sex is determined by the XY system. The man has 44 autosomes + XY, being heterogametic: 22 A + 22 A + Y. And women have 44 autosomes + XX, being homogametic: 22 A + X.

Even though male chromosomes are different from female chromosomes, these sex chromosomes are homologous and are similar in meiosis, but there are no partial chromosomes in the male chromosome, so their pairing is partial. In homologous regions, there is pairing between the X and Y chromosomes, and in non-homologous regions, there is no pairing between the X and Y chromosomes.

Man produces two types of sperm, which are composed of equal amounts of X chromosome and Y chromosome, so it is called heterogametic. The woman is considered homogametic, because in the egg she produces there is only one X chromosome. If the egg is fertilized by a sperm that has X chromosome, consequently the zygote will have an X chromosome and a Y, that means the sex of the son will be male. Otherwise, if the egg is fertilized by an X sperm, the zygote will have two X chromosomes, and its sex will be female. This whole process of defining sex occurs in fertilization.

Answer: There are two pumping systems because the right side receives blood from the body and pumps it to the lungs, and the left side receives blood from the lungs and pumps it through the body. Thereby there are two pumping systems.

Explanation:

The heart is an organ that pumps blood throughout the body through the circulatory system. Its function is to supply oxygen and nutrients to the tissues and remove carbon dioxide and waste products.

The heart is divided into two separate pumps. The right side of the heart receives oxygen-poor blood from the veins and pumps it to the lungs, Over there, the blood picks up oxygen and gets rid of carbon dioxide, wich is a waste product. On the other hand, the left side receives oxygen-rich blood from the lungs and pumps it throughout the body. This blood enters the top chamber of the right heart, called the right atrium.

So, the right side of the heart receives blood from the body and pumps it to the lungs. The left side of the heart does the opposite. Thereby there are two pumping systems.

Answer:

The correct answer will be option-B.

Explanation:

Sertoli cells are the large somatic cells present in the testis which helps in the formation of spermatozoa. The Sertoli cells create a suitable environment for the production and maturation of the sperms as they produce certain molecules which nourishes the sperms.

The Sertoli cells act as a barrier between the testis and blood and secrete enzymes like inhibin. They eliminate the apoptotic germ cells and also produce seminiferous fluid to nourish the sperm. They do not play any role in primary spermatocytes.

Thus, Option-B is the correct answer.

Answer:

B

Explanation:

Organic chemistry is defined as the study of carbon compounds.

Organic compounds were first thought to be compounds that could only be produced by living organisms. This theory was disproved when scientists synthetically made urea from ammonia in a lab.

Organic compounds are now known as compounds where carbon atoms are covalently bonded to other elements. This could be hydrogen or oxygen (in the case of lipids or carbohydrates) or nitrogen (in the case of amino acids).

Organic chemistry is the study of carbon compounds, including both naturally and synthetically produced ones, and not limited only to hydrocarbons.

Organic chemistry is most accurately defined as b. the study of carbon compounds. This branch of chemistry deals with the structures, properties, compositions, reactions, and preparation of compounds that contain carbon atoms. It's important to note that these compounds may not necessarily be produced only by living cells (which eliminates option a) and can be either natural or synthetic, ruling out option c. Furthermore, while organic chemistry does study hydrocarbons (compounds composed solely of carbon and hydrogen atoms), this makes up only a fraction of the compounds analyzed, so option d is too restrictive.

https://brainly.com/question/14623424

#SPJ6

Answer:

a.gastrulation is the correct answer.

Explanation:

The characteristics unique to animals is gastrulation

Gastrulation is a stage early in the embryonic growth in most of the animals, through which simple layered blastula is rearranged into a multi-layered structure called gastrula.

gastrulation results in the formation of three germ layers

The embryonic tissue layers are developed and arranged in their proper places during the gastrulation process.

Among the options, gastrulation is the characteristic unique to animals. Other traits like sexual reproduction, multicellularity, and flagellated sperm are also found in non-animal species, while gastrulation is a distinct phase in embryonic development of animals.

The characteristics unique to animals are not as straightforward as they may seem. Among the options, the characteristic unique to animals is gastrulation.

Sexual reproduction, multicellularity, and flagellated sperm are not unique to animals as there are non-animal species which also possess these traits. For instance, multicellularity is common in plants and fungi, sexual reproduction occurs in certain fungi and plants as well, and flagellated sperm is found in certain kinds of algae.

Gastrulation, on the other hand, is a phase early in the embryonic development of most animals, during which the single-layered blastula is reorganized into a multilayered structure known as the gastrula. This process, unique to animals, gives rise to what will become the organism's internal body cavities and the arrangement of tissues and organs.

https://brainly.com/question/18324335

#SPJ11

Answer:

1. Bacteria where grow in a medium composed of heavy nitrogen. After several generations the bacteria DNA was composed of heavy nitrogen (heavy nitrogen is an isotope of nitrogen).  

2. After several generations had passed, the bacteria were transferred to a nitrogen light medium.

3. As soon as the bacteria were transferred the bacteria DNA was isolated after the first and second generation through centrifugation.

4. Results: after 2 generations half of the DNA was intermediate and half was light; there was not heavy-only DNA.  The conclusion was that the new DNA is formed by an "old" strand and a "new" strand producing an intermediate weight.

Answer:

Explanation:

The huntington disease is a disease that is caused by the dominent allele. It is the disease which causes damage to the brain cell. The mother and father can be carrier or affected by the disease. As in the condition if both parents exhibit a hetrozygous condition that is both have a dominent as well as as a recessive allele responsible for the disease. Then there is 75% chances of occurence of disease in the child. If both parents are homozygous that is both have dominent alleles then 100% chances of occurrence of the disease.

Answer:

Since the cells are being coinfected by 2 types of viruses, this can create heteroduplex areas. DNA repair systems normally correct the heteroduplex areas. In rare cases, the heteroduplex is not corrected and a chromosome containing the mismatch appears so a single bacteriophage particle can be generated. One DNA strand is c+, and the other strand is c. When such a bacteriophage infects a fresh bacterial host cell, some molecules are created by DNA replication.

Answer:

Some bacteria are used as indicators because if they are present in the product, we can say that it is a product with the presence of pathogens that will cause diseases. Some of them are: total coliforms, fecal coliforms and enterococci.

To be a good indicator they must have a correlation with the pathogens and be more abundant than them. Its presence in a food indicates the possible presence  simultaneous pathogen microorganisms. For example, E. coli has been used as  Index of possible presence of pathogens of enteric origin in water and food

Answer:

Decrease in burning of fossil fuels will affect carbon cycle the most.

Explanation:

Carbon compounds circulate within the biosphere as part of carbon cycle.  In terrestrial ecosystems Plants acquire carbon dioxide through photosynthesis and in aquatic ecosystems plankton absorb carbon dioxide.  

Dead plants bodies deposited underground for a large number of years get converted to fossil fuels and the burning of these fossil fuels releases carbon dioxide into the atmosphere.

Carbon dioxide is also released into the atmosphere through processes like respiration and decomposition of dead organic matter. If burning of fossil fuels is decreased it will be the carbon cycle which will be affected the most.

The correct options for the reactions that occur during the Calvin cycle are: B) Carbon fixation and C) RuBP regeneration.

The Calvin cycle in chloroplast stroma involves carbon fixation and RuBP regeneration. Carbon fixation involves adding [tex]CO_2[/tex] to ribulose bisphosphate (RuBP). The enzyme RuBisCO helps produce an unstable intermediate that soon converts into two molecules of 3-phosphoglycerate (3-PGA).

These molecules then generate glucose. RuBP renewal sustains the cycle after carbon fixation. RuBP is constantly available for carbon dioxide fixation. The Calvin cycle helps plants synthesise sugars and other vital biomolecules by converting ambient carbon dioxide into organic compounds. Therefore, he correct option are: : B) Carbon fixation and C) RuBP regeneration.

Learn more about Calvin cycle, here:

https://brainly.com/question/33360156

#SPJ6

Answer:

50% green-seed individuals vs. 50% yellow-seed individuals.

Explanation:

Mendel is known as father of genetics. He explained the concept of dominance, the law of segregation and the law of independent assortment while working on pea plant.

Green seed color is recessive and yellow seed color is dominant. A pure green line seed plant (ss) is crossed with heterozygous plant (Ss). The cross is as follows:

Parents   ss (green seed)   ×     Ss (Yellow seed)

Gametes   s                                  S, s

progeny:  Ss, Ss, ss, ss.

Here, Ss is yellow seed and ss is green seed.

50% green-seed individuals vs. 50% yellow-seed individuals are formed after the cross.

Thus, the correct answer is option (a).

Answer:

Option (D)

Explanation:

Diversity in simple words means variations. By the given statement "life is diverse", it means that there are various types of life forms on earth. These variations occur in different places under different conditions. The factors that affect diversity are as follows-

(1) Biotic factors

(2) Abiotic factors

(3) Geographical factors

This diversity occurs in three forms and they are as follows-

(a) Ecological diversity

(b) Species diversity

(c) Genetic diversity

Hence, the correct answer is option (D).

Answer:

Explanation:

The resolving power of the microscope is dependent upon the objective lens. It can be measured by the ability of the lens to differentiate between the two lines or points on the specimen under observation. The more the resolving power the smaller will be the distance between the two lines or points that can be distinguished.

The following are the two ways that can be used to enhance the resolving power on the microscope:

Using a lens that has a higher aperture.

Decreasing the amount of light being entered into the microscope that means using light of less wavelength.