Vitamin K, one of the fat-soluble vitamins, plays a role in both bone health and blood clotting. There are two primary forms of the vitamin: phylloquinones and menaquinones. Choose the correct statement about vitamin K.a. Menaquinones are the primary form of vitamin K in the diet.b. Vitamin K deficiency inhibits the blood’s ability to clot.c. Excessive use of broad-spectrum antibiotics may cause vitamin K toxicity.d. The major source of vitamin K in our diets is from fortified grains.

Final answer:

The shift in the Alpine chipmunk's range is caused by climate warming due to increased CO₂ concentrations, pushing species to higher elevations.

Explanation:

According to researchers, the shift in the Alpine chipmunk's range upwards by about 500 meters, resulting in isolated subpopulations on individual mountaintops, is primarily due to climate warming due to increased CO₂ concentrations. This conclusion is based on the observation that, globally, many species are moving towards higher altitudes or latitudes in response to changing climate gradients. With the warming climate, species adapted to colder environments find their habitable zones moving uphill. As a result, these species, including the Alpine chipmunk, are forced to follow the shift in their preferred climate range, leading to higher elevations and, unfortunately, potential habitat isolation and range restriction.

Answer:

Non-native plants reduce the diversity of insect populations in gardens, even where the non-native plants are closely related to the native plants, new research shows. ... local insect communities than their non-native counterparts,

Explanation:

Non-native tree diseases and insects can be more virulent in new environments due to factors like the absence of natural predators, a lack of host plant resistance, fewer competing species, and escape from natural constraints.

Additionally, they may lack genetic diversity, undergo rapid evolution, and be spread by human activities.

These factors, combined with the vulnerability of non-native ecosystems, make them more destructive in their new environments, requiring various strategies to manage their impact.

We can conclude that the reason is because these trees do not competitors as well as the absence of predators that may have destroyed the species.

Read more on tree diseases  here https://brainly.com/question/30371757

#SPJ3

Final answer:

Homologous structures are those that have a similar structure and origin but may have different functions in various species. The example of rabbits and birds, which have the same bones in the same order in their forelimbs for different purposes, represents homologous structures.(Option D)

Explanation:

The student's question asks which of the following is an example of homologous structures. Homologous structures are those that are found in different species and share a common ancestral origin, despite possibly having different functions in the organisms where they're found.

Considering this, the correct answer is D: Rabbits and birds have the same bones in the same order in their forelimbs, even though they use them for different purposes. This resembles the forelimbs of mammals like humans, cats, and whales, as well as the wing bones of bats, which while serving different purposes, reflect a common structural plan pointing to a shared evolutionary history.

Answer:

D. just before or just after the separation of sister chromatids

Explanation:

The mitotic spindle is a structure of the eukaryotic cell cytoskeleton involved in mitosis. Their function is to separate the sister chromatids during cell division so that they are included in the daughter cells. It consists of longitudinally aligned microtubule bundles that together have an ellipsoid-like shape.

For this reason, we can state that if a drug that prevents disassembly of the mitotic spindle paralyzes the cell cycle immediately before or shortly after separation of the sister chromatids.

Answer:

37.5

Explanation:

Acording to the the Hardy-Weinberg equation:

[tex]p^2 +pq+q^2=1[/tex]

[tex]p+q = 1[/tex]

Where p is the frequency of the dominant allele "T", and q is the frequency of the recessive allele "t".

Therefore, p^2 is the frequency of the dominant homozygous genotype "TT", q^2 is the frequency of the recessive homozygous genotype "tt" and

2pq is the frequency of the heterozygous genotypes "Tt" and "tT".

Since 1 in 16 individuals have inherited two recessive alleles (tt) and have the disease:

[tex]q^2=\frac{1}{16} \\q=\sqrt{\frac{1}{16}} \\q= 0.25[/tex]

Thus, the fraction of heterozygous carriers of the studius toxicosis allele in the population is given by:

[tex]p=1-q\\p = 1 - 0.25 = 0.75\\2pq=2*(0.75)*(0.25)\\2pq= 0.375[/tex]

37.5 percent of the population are heterozygous carriers

Answer:

Endosymbiont theory was proposed by Lynn Margulis in 1967 which suggested the origin of Chloroplast and mitochondria in eukaryotic cells.

The theory suggested that chloroplast and mitochondria organelle originated by engulfing the cyanobacteria and proteobacteria by other prokaryotic bacteria.

This shows that Prokaryotes exhibit the following characters:

1. These were the first organisms on Earth

2. Lack membrane-bounded

3. Aerobic bacteria are these types of cells

Eukaryotes exhibit:

1. Have mitochondria

2. Includes organisms that carry out aerobic respiration

3. Can be a multicellular organism

4. Includes organisms that are photosynthetic

5. Might have chloroplasts

Answer:

A)Use restriction enzymes to cut the DNA at specific sequence sites.

Explanation:

Restriction enzymes cut DNA in specific sites. There are high and low frequency endonucleases. The easiest to get fragments to make the words: WILL YOU MARRY ME? is to amplify PCR fragments of known size and sequence, therefore, use restriction enzymes to cut the fragments of the desired size. It will be very useful make an in silico digestion to predict all the fragment sizes to be obtained, and a simulation of the gel before loading it.

Answer:

RNA contains an additional oxygen atom on the ribose sugar. (Ans. C)

Explanation:

RNA contains a sugar which is known as ribose, and which contains an extra group of hydroxyl (OH-) while DNA contains deoxyribose sugar.

RNA contains four nitrogenous bases cytosine, adenine, guanine, and uracil, while DNA contains cytosine, adenine, guanine, and thymine.

Double helix means two stranded structure like DNA, while RNA is single stranded.

DNA molecule is much longer polymer than RNA molecule.

Final answer:

Food in a frog's digestive system flows from the mouth, through the pharynx, esophagus, and stomach, into the small intestine for nutrient absorption, then to the large intestine for water absorption, and finally out through the cloaca as waste.

Explanation:

The path that food takes through a frog's digestive tract begins at the mouth where ingestion occurs. From there, food moves into the pharynx, then down through the esophagus and into the stomach where preliminary digestion takes place. After the stomach, food enters the small intestine where nutrients are absorbed. It then proceeds into the large intestine, where water is absorbed, and finally, the undigested waste products are expelled through the cloaca.

Answer:

Jaundice individual.

Explanation:

Jaundice may be defined as the medical condition in which the body of an individual turns into yellow. The different strains of the hepatitis virus is responsible for this infection.

The yellow color is deposited in the eyes, nails and membrane of the skin due to deposition of excess yellow orange pigment known as bilirubin. The alcohol can also cause the jaundice condition in the individual and destroys the proper liver functioning.

Thus, the answer is jaundice.

Answer:

B. 46 92 92

Explanation:

The cell cycle consists of three states:  Interphase, cell division and Resting.

The interphase is composed of the pases G1, S and G2  (in this order), through which the cell prepares itself for the cell divison,  where a single mother cell generates two (by mitosis) or four daughter cells (by meiosis).

As part of the preparation, the cell duplicates during the interphase all its genetic material (specifically in the phase S), forming replicated chromosomes. That is to say, a chromosome with two chromatides (sister chromatides).

A human cell that normally has 46 chromosomes will have in the G2 phase the same number of chromosomes: 46,  however, these chromosomes will be composed of two chromatids (instead of a single one as normally), and therefore the cell will have 92 chromatides.

Because a chromatide is made up of a strand of DNA, in the G2 phase the cell will have also 92 DNA molecules.

Answer:

B.

Explanation:

The answer is B, because bee farmers create false bee hives for h.bees to start a hive. They also can purchase a queen, (that reproduce more bees) that is her only job. The worker bees collect pollen and mix it with the bee's saliva to store honey for the hive, which also is food 4 the bees.

Answer:

The correct answer is B) Large size relative to the host chromosomes

Explanation:

A vector for clonation or expression must contain sequence elements which allow it independent replication and identification of host cells which have incorporated the vector. Among these elements are:

- Replication origin (option E): allows it to replicate independently of the host genome. Option B is the same as it.

- Restriction enzyme sites (option A): in order to cut the vector and to inser the desired gene into the vector.

- Reporter gene (option E): it allows to visualize the host cells which are expresing the inserted gene of the vector. For example, a reporter gene can codificate a fluorescent protein, thus the host cells which have expresion of the vector are fluorescent.

The only option which is unuseful is option B because if the vector has too large size, the transformation efficiency will be low. That means that fewer host cells will contain the vector after transformation.

Answer:

The four stages of the excretory system are:

1. Filtration

2. Reabsoprtion

3. Secretion

4. Excretion

Explanation:

Filtration - Waste is taken out of the bodily fluids by pressure filtration

Reabsorption - Clean bodily fluids are reabsorbed back into the body/blood

Secretion - Adding of toxins and wastes from the body fluids to the filtrate

Excretion - Expulsion/release of the waste products out of the body through urine, sweating, etc

Final answer:

The four stages/processes within a typical animal excretory system are filtration, reabsorption, secretion, and excretion. During filtration, blood is filtered in the kidneys to remove waste products and excess water. Reabsorption involves the reabsorption of useful substances, while secretion eliminates waste materials. The final stage is excretion, where the urine is passed out of the body through the urethra.

Explanation:

The excretory system in animals is responsible for eliminating waste and excess water from the body. The four stages/processes within a typical animal excretory system include filtration, reabsorption, secretion, and excretion.

Filtration: In this stage, blood is filtered in the kidneys to remove waste products and excess water. Small molecules like water, glucose, amino acids, and ions pass through the filtration membrane, while larger molecules like proteins and blood cells are retained.

Reabsorption: During reabsorption, useful substances like glucose, amino acids, and ions are reabsorbed from the filtrate back into the bloodstream. This process helps maintain the body's essential nutrients and ions.

Secretion: Secretion involves the active transport of waste products, toxins, and excess ions from the bloodstream into the filtrate. This further helps in eliminating waste materials that were not filtered during the initial stage.

Excretion: The final stage of the excretory system is excretion, where the filtrate, now known as urine, is passed out of the body through the urethra. Urine is a concentrated solution containing waste products like urea, water, excess ions, and other substances.

From the following macromolecules which enter the nucleus of a eukaryotic cell through pores in the nuclear membrane is mRNA. The correct option is c.

Macromolecules are big molecules, such as proteins, that are usually formed through the polymerization of smaller subunits known as monomers.

The nuclear pore is a conduit in the nuclear envelope that is lined with proteins. The nuclear pore controls the movement of molecules between the nucleus and the cytoplasm. The nucleus in eukaryotic cells is isolated from the cytoplasm and surrounded by a nuclear envelope.

mRNA is generated by DNA during the transcription process. Following synthesis, the newly formed molecule goes from the nucleus to the cytoplasm. A nuclear pore allows it to pass through the nuclear membrane. It will then connect with a ribosome, which is just coming assembled from two subunits, one large and one little.

Thus, the correct option is c.

Learn more about mRNA here,

https://brainly.com/question/29316969

#SPJ3

C)mRNA is the macromolecule that enters the nucleus of a eukaryotic cell through the pores in the nuclear membrane.

The nuclear pores allow large molecules such as mRNA transcribed from genes in the DNA to leave the nucleus and enter the cytoplasm to participate in protein synthesis.

Additionally, the RNA components of ribosomes are synthesized in the nucleolus, and after being produced, ribosomes are exported to the cytoplasm.

The question is incomplete. The complete question is:

Plasmodesmata are cell junctions that are found between ________.

a) adjacent animal cells in the same tissue type

b) individual cardiac cells in heart muscle tissue

c) the plasma membrane of actively dividing prokaryotes

d) adjacent plant cells

Answer:

d) adjacent plant cells

Explanation:

Plasmodesmata are the cytoplasmic channels that connect the adjacent plant cells together and maintain the continuity of their cytoplasm. These are the narrow channels with 20-40 nm diameter. Plasmodesmata serve the function analogous to the gap junctions of the animal cells.  The presence of plasmodesmata between the neighboring plant cells allows the movement of molecules and ions between them. Plant cells can adjust the diameter of the plasmodesmata according to the requirement to allow the transport of substances across them.

Plasmodesmata are cell junctions found specifically between adjacent plant cells, facilitating transport and communication within plant tissues.

The question relates to plasmodesmata, which are cell junctions found between adjacent plant cells. Plasmodesmata are channels that allow the transport of ions, small molecules, and macromolecules between the cytoplasm of adjacent cells, thus facilitating communication and transport of materials within plant tissues. They are found within the cell wall and are sheathed by the plasma membrane, which is an extension of the plasma membrane of adjoining cells. This intercellular connection raises the concept of plant tissue as a potential syncytium—a network of cells sharing a common cytoplasm.

In contrast, animal cells utilize gap junctions for similar cellular communication. Gap junctions are formed by the alignment of pores of connexons—complexes made of six proteins called connexins—between adjacent animal cells, which is particularly important in cardiac muscle tissue. However, these are not found in plants and thus not related to plasmodesmata, which are unique to plant cells.

On the other hand, prokaryotes, such as bacteria, lack specialized intercellular junctions because they do not have multicellular structures like eukaryotes. Instead, they may communicate through direct contact or by releasing and detecting signaling molecules.

Answer:

Mutation that prevents Transcription Factors Dimerisation

Mutation that prevents Transcription Factors from binding to Chromatin Remodeling proteins.

Mutation that prevents Transcription Factors from binding DNA

Mutation that prevents binding of co- activator

Explanation:

Several different mutations can affect Transcription Activators to be  unable to promote transcription of its target gene:

1. Mutation that prevents Transcription Factors Dimerisation: In the given example, because the Transcription Factors requires dimerisation to function. A mutation that disrupts dimer formation will prevent the Transcription Factor from activating gene transcription.

2. Mutation that prevents Transcription Factors from binding to Chromatin Remodeling proteins: Since this transcription activator results in Chromatin remodeling, a mutation in the domain that binds to and recruits chromatin remodeling proteins will prevent the transcription factor from being able to promote chromatin remodeling.

3. Mutation that prevents Transcription Factors from binding DNA: A mutation that abrogates either the ability or the specificity of transcription Activator to bind to DNA will prevent the activator to effectively promote transcription of target gene.

4. Mutation that prevents binding of co- activator: Many activators promote transcription from a locus in the presence of a co-activator. A mutation that prevents the binding of the activator to the activator will prevent expression of the target gene.  

Answer:

The correct answer will be option-B

Explanation:

Dominance is the phenomenon observed in the genes coding for a trait in which the one variant of a gene called allele masks the effect of a complementary allele at same locus coding for the same trait.

The concept of dominance was observed by Gregor Mendel during his experiments on Pea related to study the inheritance pattern.

Since in dominance, one allele masks the effect of complementary allele therefore the dominant allele shows its effect and different genotypes produce the same phenotype.

Thus, Option-B is the correct answer

A substitution missense affects only one codon, but a frameshift missense affects all codons downstream of the frameshift.

A frameshift mutation occurs during deletion of one of two nucleotides. The arrangement of codons downstream of the mutation will definitely change, hence it being called a frameshift mutation. On the other hand, a substitution mutation will only cause a change in one nucleotide of one codon.

Explanation:

A frameshift mutation causes new codons downstream of the mutation that will code for different amino acids hence changing the properties of the translated proteins. This will have great ramifications for the phenotype of the organism.

On the other hand, substitution mutation will only cause a change in the amino acid at that point of mutation during translation. This will not have a drastic change in the protein hence will not be as lethal as a frameshift mutation.

Learn More:

For more on mutations check out;

https://brainly.com/question/11278415

#LearnWithBrainly

A frameshift mutation typically has a more severe effect on protein function than a nucleotide-pair substitution missense mutation because it changes the reading frame, leading to widespread amino acid changes and potentially a nonfunctional protein, while a missense mutation usually alters a single amino acid and may still produce a functional protein.

A frameshift mutation is caused by insertions or deletions of nucleotides that are not in multiples of three, leading to a major shift in the genetic reading frame. This results in a different set of amino acids being encoded from the mutation point onward, which often produces a nonfunctional protein. Contrarily, a nucleotide-pair substitution mutation, also known as a missense mutation, typically changes only a single amino acid in the protein. This type of mutation has a less profound effect compared to a frameshift mutation because it does not alter the reading frame for the rest of the coding sequence.

A missense mutation from a nucleotide-pair substitution may sometimes lead to a protein that retains functionality, especially if the new amino acid is chemically similar to the original. However, if that amino acid is in a critical part of the protein, such as the active site, then the consequences can be more severe. In contrast, a frameshift mutation can result in a completely altered protein with many incorrect amino acids, which is more likely to be nonfunctional and have a severe effect on the phenotype.

It is important to note that while a missense mutation affects only the specific codon where the substitution occurs, a frameshift mutation has the potential to affect all downstream codons after the mutation point. Additionally, a frameshift mutation can introduce an early stop codon, prematurely ending the protein, while a missense mutation does not introduce a stop codon and usually only impacts the incorporation of a single amino acid.

https://brainly.com/question/14086778

#SPJ12

The correct answer is a) Systemic acquired resistance

Explanation:

In biology, systemic acquired resistance occurs as one organism develops resistance to a specific pathogen such as a virus or bacteria, this means, the organism's system recognizes previous pathogens it has been exposed to and in this way responds appropriately. The systemic acquired resistance occurs mainly in plants and due to this, it is believed this response is similar to one of the immune systems in animals. Therefore, the mechanism that is the closest process plants have to an immune system is Systemic Acquired Resistance or SAR.

Answer:

a. lactic acid fermentation

Explanation:

Under conditions of intense exercise, the oxygen gas obtained by pulmonary respiration may be insufficient to meet the needs of muscle cells in the work of obtaining energy from cellular respiration.

However, even in the absence of oxygen gas, our muscle cells can release the available energy in glucose, leading to even smaller amounts of ATP molecules. Under these conditions, muscle cells perform lactic fermentation, a process that is virtually identical to glycolysis (the first set of cellular respiration reactions), except that pyruvic acid is transformed into lactic acid with the formation of 2 ATPs.  Despite the lower energy yield, fermentation ensures the energy supply to the muscle. Lactic acid formed under these conditions has been associated with muscle pain and fatigue characteristic of intense physical exercise. Recent research, however, has shown that pain is caused by muscle fiber micro-injuries rather than lactic acid as it is rapidly metabolized and eliminated.

Answer:

The genes are linked and 10 mu apart.

Explanation:

A female AaBb rabbit is test crossed with a male rabbit (aabb). The male can only produce ab gametes (all the progeny will have ab on one of the homologous chromosomes).

If the genes assorted independently, the female would produce 4 types of gametes with the same frequency: 1/4 AB, 1/4 Ab, 1/4 aB and 1/4 ab.

However, the observed AB and ab gametes were much more frequent than Ab and aB, which means that the genes are linked and alleles on the same chromosome do not assort independently during meiosis.

Recombination is a rare event, so the most abundant gametes are the parentals. That is how we know that the mother had the AB/ab genotype. The recombinant gametes therefore are Ab and aB.

Distance (mu) = # Recombinants × 100/ Total progeny

Distance = (54 + 46) × 100/ 1000

Distance =  100 × 100/1000

Distance = 10 mu

Answer:In glycolysis , Oxygen + Pyruvate molecules = acetyl-CoA + CO2

Where "=" means in the presence of enzyme complex pyruvate dehydrogenase complex (PDC)

Acetyl-CoA - NADH

Pyruvate oxidation or Pyruvate decarboxylation also known as link reaction, is the conversion of pyruvate into acetyl-CoA by the enzyme complex pyruvate dehydrogenase complex

Explanation:

A carboxyl group is trimmed off of Pyruvate and released as a molecule of carbon dioxide, leaving behind a two carbon molecule.

The two carbon molecule from above is oxidised - Acetyl group, and the electrons lost in the oxidation are picked up by NAD+ to form NADH

An acetyl group is transfered to Coenzyme A, resulting in acetyl CoA

Answer: A (catabolism and Anabolism)

Explanation:

Metabolic pathway are basically divided into two categories.

1. Catabolic

2. Anabolic

Catabolic (degradation) pathways, where energy rich complex macramolecules are degraded into smaller molecules. Energy released during this is trapped as chemical energy, usually as ATP.

Anabolic (biosynthesis) pathways. The cells synthesize complex molecules from simple precursors. This needs energy.

No, in a ladybug mutant lacking the D gene, the spot cells would not be able to make black pigment.

The developmental pathway indicates that the expression of black pigment in spot cells (ectoderm cells) depends on the presence of the D gene. Without the D gene, the pathway is interrupted, and the subsequent steps (Y → B) that lead to the production of black pigment cannot occur.

Therefore, in a ladybug mutant lacking the D gene, the spot cells would not be able to make black pigment.

Learn more about ladybug mutant

https://brainly.com/question/15573698

#SPJ3

Answer:

The correct option is A. An airplane lifting into the sky during take- off.

Explanation:

The force of the gravitational pull is known to act downwards. The objects which will move along this force i.e will move downwards will have positive action.

A negative action will act against the gravitational pull i.e a force that is applied in the upward direction. As an aeroplane is lifted upwards during taking- off i.e against the gravitational pull of the earth hence it will be considered as a negative action.

Answer:

dendrites

Explanation:

The neuron consists of a cell body and extensions called dendrites. In some neurons, one of the dendrites is elongated to form an axon. There are terminal and receptor dendrites. Receptor dendrites make contact with terminal dendrites of neighbouring neurons or receptor organs while terminal dendrites make contact with receptor dendrites of another adjacent neurons or effector organs.

Answer:inherited 33 chromosomes from each parent; gametes have 33; somatic cells of offspring 66.

Explanation: S. sempervirens is sn autohexaploid, as were its parents. It inherited 33 chromosomes from each parent, and that is the chromosome number in its gametes, which means its offspring’s somatic cells will have 66 chromosomes

Answer:

Endothermic reactions:  separation of solute molecules , separation of solvent molecules

Exothermic: formation of solute-solvent interactions

Explanation:

An endothermic reaction can be described as a reaction which requires energy. Usually, the energy is taken in the form of heat from the environment. For example: the separation of solute and solvent molecules.

An exothermic reaction can be described as a reaction in which energy is released during a reaction. For example, a solute and a solvent reaction. Energy is usually released in the form of heat during an exothermic process.

Classifying the steps involved in the formation of a solution as being endothermic or exothermic:

endothermic

exothermic

In this reaction heat or energy is absorbed in the process of producing the product. Breaking of bonds requires energy, so the separation term is endothermic.

separation of solute molecules and separation of solvent molecules both are endothermic.

With the product formation, energy or heat is also released in such a reaction. The interaction of solute solvent is exothermic as it releases heat in the process.

Learn more about the exothermic reaction:

https://brainly.com/question/2924714