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Oxygen carried in a hemoglobin molecule is bound to a/an

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Oxygen carried in a hemoglobin molecule is bound to an iron atom. 
The red blood cells contain a pigment called hemoglobin, each molecule of which binds four oxygen molecules.
This protein carries oxygen to the cells and carbon dioxide to the lungs. 
It is the iron atom that binds oxygen as the blood travels between the lungs and the tissues.

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The sides of the DNA molecule, that rails of the ladder, are composed of

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The sides of the DNA molecule, that rails of the ladder, are composed of

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How many molecules of DNA would result from one molecule after four cycles of PCR A.4 B.16 C.32 D.2

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Answer: B.16

Explanation

The polymerase chain reaction (PCR) is a technique used in molecular biology to make millions of copies DNA from a small amount of it. To acomplish this, short segments of DNA called primers are designed to each chain of the DNA that is going to be copied. Then, the DNA polymerase adds nucleotides to theose primers that will be complementary to the DNA chains. After one molecule is amplified, a new molecule is amplified using that one and so on and so forth. Then, 2 chains are amplified in one cycle to get 2 molecules (with two chains each) Thereby, the replication rate of DNA is exponential, then it is calculated as:

1 x (2^4) = 16 DNA molecules.

1= molecule

2= chains per molecule

4= number of cycles

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Which is a non-polar molecule? A. Hydrogen Chloride (HCI) B.Oxygen Difluoride (OF2) C. Sulfur Hexachloride (SF6) D. Hydrogen Cyanide (HCN) E. Trifluoromethane (CHF3)

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Which is a non-polar molecule? A. Hydrogen Chloride (HCI) B.Oxygen Difluoride (OF2) C. Sulfur Hexachloride (SF6) D. Hydrogen Cyanide (HCN) E. Trifluoromethane (CHF3)

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Why is water an excellent solvent for most ionic compounds and polar covalent molecules but not for non-polar compounds? A) Water is a polar molecule. B) Water has a charge like an ion. C) Water is a deionizing substance. D) Water molecules have an unusually high kinetic energy in the liquid state.

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A)Water is a polar molecule. When talking about solubility, the rule that “like dissolves like” is usually correct. This means that polar substances are soluble in other polar substances. This occurs because the opposite partially charged ends of different polar molecules are attracted to each other. Similarly, the partially charged ends of polar molecules will be even more attracted to the charged ends of an ionic compound’s molecule. This is why,for example, table salt/ NaCl, which is an ionic compound, dissolves in water. 

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Anonymous 5 years ago A molecule that can be used as a molecular clock has a neutral mutation rate of one mutation per 5 million years. How many years ago did two species share a common ancestor if the molecules found in these two species differ by a total of eight mutations? Answer a) 1.5 million years b) 10 million years c) 20 million years d) 40 million years

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Anonymous 5 years ago A molecule that can be used as a molecular clock has a neutral mutation rate of one mutation per 5 million years. How many years ago did two species share a common ancestor if the molecules found in these two species differ by a total of eight mutations? Answer a) 1.5 million years b) 10 million years c) 20 million years d) 40 million years

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If the rate-determining step limits the speed of a reaction, which statement is correct? Even if one or more fast steps occur in a reaction, the overall reaction cannot proceed any faster than the slowest step. If the first step is slow and the second step is fast, then the second step should determine the rate of the overall reaction. Increasing the concentration of a molecule that occurs in a fast step after a slow step will increase the overall rate of the reaction. In a unimolecular reaction where A decomposes to B and C, the rate of the reaction will decrease if the concentration of A is increased.

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A positive cahnge of enthalpy, ΔH rxn = + 55 kJ/mol, for the forward reaction means that the reaction is endothermic, i.e. the reactants absorb energy and the products are higher in energy.

Activation energy is the difference in the energy level of the reactants and the peak in the potential energy diagram (the energy of the transition state).

For an endothermic reaction, the products will be closer in energy to the transition state than what the reactans will be; so, the activation energy of the reversed reaction is lower than the activation energy of the forward reaction.

Activation energy of reverse and forward reactions is related by:

Activation energy of reverse rxn = Activation energy of forward rxn – ΔH rxn

=> Activiation energy of reverse rxn = 102 kJ/mol – 55 kJ/mol = 47 kJ/mol

Answer: 47 kJ/mol

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The molecule ethylbenzene is considered an…. A. Alkane B. Alkyne C. Cycloalkane D. Cycloalkene

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The molecule ethylbenzene is considered an…. A. Alkane B. Alkyne C. Cycloalkane D. Cycloalkene

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What is an intron? a part of DNA that codes for a functional protein a part of DNA that does not code for a functional protein the beginning part of the DNA molecule the end of part of the DNA molecule

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Answer:

Helicases unwind the two parental DNA’s strands and creates the replication fork; single strand binding proteins keep the single strand from joining.


Further information:

• DNA replication: a biological method occurring in all living organisms that is the basis for biological inheritance

Helicase: It is an enzyme that may unwinds the DNA helix ahead of the replication machinery.

Origin of replication: a specific sequence in a genome at which replication is started.


Steps of DNA replication:

• During initiation, proteins fix to the source of replication while helicase unwinds the DNA helix and two replication forks are formed at the source of replication.

• During elongation, a primer sequence is added with complementary RNA nucleotides, which are then substituted by DNA nucleotides.

• During elongation the leading strand is made constantly, while the lagging strand is made in portions called Okazaki fragments.

• During termination, primers are detached and substituted with new DNA nucleotides and the backbone is stuck down by DNA ligase.

Purpose of DNA replication:

The purpose of DNA replication is to produce two duplicate copies of a DNA molecule. This is essential for cell division during development or repair of damaged tissues. DNA replication ensures that each new cell receives its own replica of the DNA.

Answer details:

Subject: Biology

Level: High school

Keywords:

• DNA replication

• Helicase

• Origin of replication

• Steps of DNA replication

Learn more to evaluate:

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brainly.com/question/10652950

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A molecule in which the central atom has no lone pairs and forms four single bonds is said to have a ________ shape.

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A molecule in which the central atom has no lone pairs and forms four single bonds is said to have a ________ shape.

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If 28% of the nucleotides in a dna molecule contain the base t, what percent will contain the base g? enter your answer as a whole number without the percent sign. for example, 5% would be entered as 5 and 37% would be entered as 37.

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A DNA is composed of
groups called nucleotides. One component of nucleotide is the nitrogen bases.
The nitrogen bases are:

Adenine (A), Thymine (T), Guanine
(G) and Cytosine (C)

 

Where inside the
nucleotides the amount of these bases are,

amount of base A = amount
of base T

amount of base G = amount
of base C

 

So if the nucleotide is
composed of 28% base T then base A would also be 28% leaving us with 100 – 56 =
44% remaining composition.

Since base G and base C
has also same amounts, therefore it will contain 22% base G and 22% base C.

ANSWER: 22

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Which is a typical characteristic of an ionic compound? a. electron pairs are shared among atoms. b. the ionic compound has a low solubility in water. c. the ionic compound is described as a molecule?

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Which is a typical characteristic of an ionic compound? a. electron pairs are shared among atoms. b. the ionic compound has a low solubility in water. c. the ionic compound is described as a molecule?

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In the covalent bond between hydrogen and chlorine in the HCl molecule, where will the majority of shared electrons be found? A.near the hydrogen atom B.near the chlorine atom C.equidistant from both atoms D.away from chlorine atom E.away from both atoms

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When ammonia is added with water, it forms a lonely OH- ion and a conjugate acid of HNH3+, or NH4+. Just based on the formula alone, a basic hydroxide is one of the products from NH3 and H2O, which is usually a tall-tale sign of NH3 being basic. Also, the reaction can also be reversed, so that (OH-)+(NH4+) -> H2O+NH3.

If this question has a different chemical formula, with either a H+ (hydrogen atom/proton) or a H3O+ (hydronium) as one of the products, then the compound that is being hydrolyzed (H2O is added to it) is acidic.

Hope this answers the question.

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Which characteristic of water allows its molecules to form hydrogen bonds? The water molecule is polar. Water has a low specific heat. Ionic bonds hold the water molecule together. Water expands as it freezes.

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Answer:

1) Water has very high specific heat.

2) It expands when it freezes

3) ability to dissolve in ionic substances

4) Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid.

Explanation:

1) Water molecules due to their high specific heat , undergo relatively less increase in temperature after absorbing heat. So they prevent their adjoining area to experience sharp increase in temperature.

2) Water is an example which expands on freezing. In it , large spaces are left between molecules when it cools. It happens because hydrogen bonds prevent any two molecules to come very close thereby  creating gaps. This gap is filled up when ice melts , which results in overall reduction in volume of water.

3) Uneven distribution of charge results in water molecules becoming polar in nature . A polar substance  can be dissolved in polar solvents only.

4) It is due to property of surface tension. Property  of surface tension results due to molecules of water near the surface experiencing a  net downward  force due to hydrogen bonds . It is due to fewer hydrogen bonds made by them.

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How many carbon atoms are found in a molecule of 2-methyl-3-nonene? 8 9 10 11

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How many carbon atoms are found in a molecule of 2-methyl-3-nonene? 8 9 10 11

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The polar portion of a cholesterol molecule, which forms hydrogen bonds with the polar heads of neighboring phospholipids and glycolipids, consists of a

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The balanced chemical reaction is as shown below,

                 N₂ + 3H₂  –> 2NH₃

The equation shows that every 3 moles of hydrogen, H2, there would be 2 moles of ammonia, NH3, that is going to be formed. Using this concept, we solve for the unknown in this item. 

Since we are restricted only of the number of hydrogen, it becomes our limiting reactant. 

          (6 moles H2) x (2 moles NH3/3 moles H2) = 4 moles NH3

Therefore, given enough amount of N2, the amount of NH3 that can be formed out of the 6 moles of H2 is equal to 4 moles. 

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How many carbon atoms are in the fragment that is fed into the citric acid cycle to bind with oxaloacetate and what is this molecule called?

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How many carbon atoms are in the fragment that is fed into the citric acid cycle to bind with oxaloacetate and what is this molecule called?

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Areas near oceans or large lakes tend to have more moderate climates than do areas far from large bodies of water. Which of these statements best explains this observation? Hydrogen and oxygen atoms share electrons in a water molecule. Lakes and oceans contain dissolved solids. Water has a very high specific heat. Water produces buoyant forces. Question 2(Multiple Choice Worth 2 points) A scientist discovers a new substance. The molecules of the substance form hydrogen bonds with each other. When the molecules lose a lot of energy, the hydrogen bonds hold them relatively far apart. Based on this information, what can the scientist infer about the substance? It expands when it freezes. It is highly colored. It exists only as a gas. It does not dissolve ionic compounds. Question 3(Multiple Choice Worth 2 points) Which of the following properties of water is due primarily to the uneven distribution of charge between the hydrogen and oxygen atoms? its color its taste its ability to dissolve ionic substances its ability to produce buoyant forces Question 4(Multiple Choice Worth 2 points) A drop of water placed on a smooth, dry surface will form a dome-shaped droplet instead of flowing outward in different directions. Which of these best explains this observation? The bonds between hydrogen and oxygen atoms are very strong. The electrons in the atoms attract the electrons in the other atoms. Water molecules at the surface experience fewer hydrogen bonds than water molecules within the liquid. Water molecules near the surface produce more buoyant force than water molecules within the liquid.

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The gravitational force Fg between two objects is given by the equation:

Fg=(G*m₁*m₂)/r₂, where G=6.67*10^-11 m³ kg⁻¹ s⁻² is the gravitational constant, m₁ and m₂ are the masses of the two bodies and r is the distance between those bodies. 

Due to the gravitational attraction the pencil and the eraser will attract if we there is no friction on the surface. 

m₁=10 g=0.01 kg is the mass of the pencil
m₂=20 g=0.02 kg is the mass of the eraser
r=2.5 cm = 0.025 m

First we calculate the Fg:

Fg={(6.67*10^-11)*0.01*0.02}/(0.025²)=2.1344*10^-11 N

To get the velocity v of the pencil:

v²=2as, where a is the acceleration of the pencil and s is the path. In our case s=r so we can write:

v²=2ar

a=Fg/m₁= 2.133*10^-9 m/s²

v²=2*(2.133*10^-9)*0.025=1.0665*10^-10

v=√(1.0665*10^-10)=1.0327*10^-5 m/s

We have the velocity and the acceleration, so we can calculate the time t with the equation:

t=v/a=(1.0327*10^-5)/(2.133*10^-9)=4841.6 s

1 hour has 3600 s so when we divide time t in seconds by 3600 we get time T in hours:

T=t/3600=4841.6/3600=1.3449 h. 

So the time for the pencil and eraser to touch is T=1.3449 hours. 

Also time T can be expressed like T= 1h and 20 mins and 41.64 s

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How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule

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How many carbon dioxide molecules are produced by the complete aerobic breakdown of one glucose molecule

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A water molecule consists of an oxygen atom with two hydrogen atoms bound to it. the angle between the two bonds is 106? .

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There are primarily three subatomic particles in an atom;
Protons
Electrons
Neutrons
—————-
Protons are positively charged subatomic particles in an atom. These particles give an element it’s identity, based on it’s ‘Atomic Number’, or how many protons are contained in the atom.

Electrons are negatively charged subatomic particles in an atom. These particles give an element it’s reactivity, and are a major part in finding where an element lies on the Periodic Table by valence electrons. We can discuss more of this in PM if you’d like to know more about this. Electrons are also a major part of finding an element’s ‘atomic mass’, or how many neutrons it has.

Neutrons are subatomic particles in an atom that have a neutral or ‘no’ charge. These are inside of the nucleus of an atom, as opposed to protons and electrons, which are farther outward of the center of an atom.

To answer your question, and reading from the text above, ‘Neutrons’ is your answer.

I hope this helps!

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The maltose molecule can be broken down into two individual glucose molecules with the help of an enzyme produced within a cell. Which of the following changes is most likely to slow down this reaction? A. Adding more maltose molecules B. Increasing the volume of the cell C. Adding more of the enzyme D. Increasing the pH within the cell

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Answer: 1. It results from the disappearance of entire species in a short time.

3. It is caused by the growth of the human population.

6. It is caused by an increase in the introduction of non-native species.

Explanation:

A mass extinction can be define as death of large population of a species due to natural hazard or due human induced impacts over the environment.

Following are the examples of human created mass extinction:

1. It results from the disappearance of entire species in a short time.: Human induced impacts like nuclear explosion can lead to the disappearance of the entire species in short time.

3. It is caused by the growth of the human population.: With the advent of human population worldwide the demand for resources like habitat, water, food and other needs increased. This lead to the extinction of many flora and fauna species.

6. It is caused by an increase in the introduction of non-native species. : A non-native species if introduced by human intervention into a natural ecosystem may compete for native species for resources. This may lead to the extinction of inferior native species.

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What is the empirical formula for a molecule containing 46.8% Si and 53.2% O

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Answer:  AB + CD rightarrow AD + CB is a replacement reaction.

Explanation:

A reaction which involves replacement of chemical species of two or more reactant molecules is known as replacement reaction.

In the reaction, AB + CD rightarrow AD + CB, B is replaced by D and D is replaced by B. Hence, this reaction is a replacement reaction.

A synthesis reaction is a reaction in which two or more species combine to form a single product.

A decomposition reaction is a reaction in which a chemical specie decomposes or breaks to give different products.

Oxidation reaction results in a change in the oxidation state of chemical species involved in the reaction. Therefore, this reaction is not an oxidation reaction as no change in oxidation state is given

Thus, we can conclude that AB + CD rightarrow AD + CB is a replacement reaction.

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While looking at a cell under a microscope, a scientist is able to see a biological molecule. This molecule is a nucleic acid with double strands and contains the nitrogenous bases adenine, thymine, cytosine, and guanine. Based on this information, what conclusion can the scientist draw regarding this nucleic acid

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While looking at a cell under a microscope, a scientist is able to see a biological molecule. This molecule is a nucleic acid with double strands and contains the nitrogenous bases adenine, thymine, cytosine, and guanine. Based on this information, what conclusion can the scientist draw regarding this nucleic acid

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In a hydrocarbon’s name, what does the suffix –yl indicate about the molecule? There is a double carbon bond in the molecule. There is a double hydrogen bond in the molecule. There is a substituent in the molecule. There is a triple carbon bond in the molecule.

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Answer : The correct option is, pain relievers

Explanation :

  • Aromatic hydrocarbons : It is usually contain benzene rings (six membered rings) of carbon atoms with alternating C-C single and C=C double bonds.  Aromatic hydrocarbon compounds are found everywhere like in pain relievers and in flavoring agents.

Pain relievers  : It is a type of medicine which help in reducing any type of pain or fever. Some pain relievers are, aspirin, acetaminophen, ibuprofen, etc and the benzene ring is found in aspirin, acetaminophen, and ibuprofen.

Polyvinyl chloride and Clothing  : Both are the type of polymer in which a large molecule of high molecular weight formed by the combination of one or more types of molecules of low molecular weight. In this compound, no benzene ring is present, it has linear or cross-linked structure.

Barbeque fuel  : In the barbeque fuel, oil is used which contains saturated and unsaturated hydrocarbons.

Hence, the pain relievers is composed of aromatic hydrocarbons.

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How many sigma bonds are there within a water molecule

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Answer: B. Water forms strong hydrogen bonds.

Explanation:

The forces between the molecules of similar substances are called as cohesive forces and the forces between the molecules of different  substances are called as adhesive forces.

Boiling point is the temperature at which vapor pressure of the liquid becomes equal to atmospheric pressure.

Boiling point depends on the strength of inter molecular forces. The molecules of water are bonded through strong hydrogen bonds between electropositive hydrogen and electronegative oxygen and thus have strong cohesive forces.

In order to make the vapor pressure equal to atmospheric pressure, the liquid needs to be heated more and thus has higher boiling point.

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