biology review

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Specific data collected from a lab experiment would best be used in which section of scientific writing? *

Evidence

If a doctor injected a patient with what was labeled as an isotonic saline (salt water) solution, but then the patient died, and an autopsy revealed that several of the patient's red blood cells had burst, would it be true that the injected solution was really isotonic?

False, the solution was hypotonic.

Why is it advantageous for the plasma membrane to be fluid in nature? Fluidity allows greater flexibility to the cell and motion of membrane components required for transport. Fluidity helps only in transport of some materials, and does not contribute to the flexibility. Fluidity helps in maintaining the pH of intracellular fluid, and helps in maintaining the physiological pH of the cell. Fluidity helps in providing mechanical strength to the plasma membrane.

Fluidity allows greater flexibility to the cell and motion of membrane components required for transport.

An experiment was set up to determine the movement of molecules through a dialysis-tubing bag into water. A dialysis-tubing bag containing 5% lactose and 5% fructose was placed in a beaker of distilled water, as illustrated. After four hours, fructose is detected in the distilled water outside of the dialysis-tubing bag, but lactose is not. What conclusions can be made about the movement of molecules in this experiment? *

Fructose, being a monosaccharide, diffused through the dialysis bag into the distilled water. However, lactose, being a disaccharide, could not diffuse through the dialysis bag.

what charge do hydrogens have on a water molecule?

(+) positive

An 8% starch solution is placed inside a selectively permeable cellulose membrane. The membrane is then submerged in a hypotonic solution. Which of the following could be the starch concentration of the hypotonic solution? 1% 8% 10% 50%

1%

Carbon has ______ valance electrons. *

4

How are cohesion and surface tension related to the chemical properties of water?

All are properties related to hydrogen bonding.

Why would phospholipids organize themselves this way if they were submerged in water? * The hydrophobic tails don't like water so they move inward The hydrophilic heads like water and stay around water The hydrophilic heads shield the hydrophobic tails All of the above

All of the above

What characteristics do all cell surface receptors share? They are composed of proteins. They all must bind to a molecule to be activated. They all are shape-specific to a signal molecule. All of the answer choices are correct.

All of the answer choices are correct.

Saw the first bacteria and made one of the first microscopes. Theodore Schwann Rudolf Virchow Anton van Leeuwenhoek Robert Hooke Matthias Schleiden

Anton van Leeuwenhoek

What element is the basis of all life

Carbon

All of the following statements are true about carbon EXCEPT * One carbon atom can form up to 4 covalent bonds. Carbon forms ionic bonds with hydrogen atoms. Carbon forms a wide variety of organic compounds. A carbon atom can bond to other carbon atoms to form long chains.

Carbon forms ionic bonds with hydrogen atoms.

Which of the following statements regarding carbon is FALSE. * Carbon has a tendency to form covalent bonds. Carbon has the ability to bond with up to six other atoms. Carbon has the ability to form single and double bonds. Carbon has the ability to bond together to form extensive branched or unbranched "carbon skeletons"

Carbon has the ability to bond with up to six other atoms.

The older a student is, the more money they usually donate. This is an example of *

Claim

What is the fundamental difference between covalent and ionic bonding? *

Covalent bonds form between atoms of the same element; ionic bonds form between atoms of different elements.

A shortage of phosphorus in the soil would make it especially difficult for a plant to make

DNA

Which of the following options correctly pairs a polymer and its monomer? cellulose, amino acids DNA, nucleotides collagen, nucleic acids RNA, ribose

DNA, nucleotides

A child is brought to the hospital with a fever of 107F. Doctors immediately order an ice bath to lower the child's temperature. Which of the following statements offers the most logical explanation for this action?

Elevated body temperatures may denature enzymes. This would interfere with the cell's ability to catalyze various reactions.

Which of the following statements regarding enzyme function is false? An enzyme's function depends on its three-dimensional shape. Enzymes are very specific for certain substrates. Enzymes are used up when the catalyze a chemical reaction so they must be synthesized for each new chemical reaction. Enzymes emerge unchanged form the reactions they catalyze.

Enzymes are used up when the catalyze a chemical reaction so they must be synthesized for each new chemical reaction.

Which of the following statements regarding enzymes is TRUE? Enzymes are inorganic. An enzyme's function is unaffected by changes in pH. Enzymes catalyze specific reactions. Enzymes depend on protein cofactors to function.

Enzymes catalyze specific reactions.

A cell model containing 90% water, enclosed in a selectively permeable membrane, has just been put in a beaker with a solution that is 70% water. The membrane allows water and glucose to pass through, but won't let salt through. Which substance(s) will have a net movement INTO the cell? Glucose Water Salt Glucose and water None of the above

Glucose

With our butter sandwich activity, what did the bread represent?

Hydrophilic heads of the phospholipids

Discuss why the following affect the rate of diffusion: molecular size, temperature, and the distance that must be traveled.

Larger molecules move slower than lighter molecules. Increasing or decreasing temperature increases or decreases the energy in the medium, affecting molecular movement. Greater distance slows the diffusion.

You can find DNA in every living organism. This shows:

Living things are based on a Universal Genetic Code.

An amoeba uses a pseudopod to surround and absorb another organism. This best shows:

Living things obtain and use materials and energy.

Your body normally maintains a temperature of 98.6° F. This is an example of what characteristic of life? *

Maintain homeostasis

If you observe a cell with a lot of chloroplasts, what would you expect the cell to be really efficient at doing?

Making glucose

Stated that plants are made of cells. * Theodore Schwann Rudolf Virchow Anton van Leeuwenhoek Robert Hooke Matthias Schleiden

Matthias Schleiden

"Eat a good breakfast and you will be able to run longer." This is an example of

Metabolism/Use energy

You have just bought a salt water aquarium. You go to the pet store to buy fish and put your new fish in your aquarium. You later discover the fish you purchased was a freshwater fish. Can that fish survive in your aquarium? *

No, you have placed your fish in a hypertonic environment, fish cells will crenate and it will die.

Which of the following statements regarding nucleotides is false? Nucleotides contain lipids. Nucleotides contain sugar molecules. Nucleotides can be linked together to form nucleic acids. Nucleotides contain nitrogenous bases.

Nucleotides contain lipids

would a molecule with a carboxyl, amino, and methyl group like water?

Part of it would like water and part of it would not because the carboxyl group and amino group like water and the methyl group does not.

________ cells LACK a membrane-enclosed nucleus.

Prokaryotic

Observing a cell under a microscope, you notice that the cell has a flagella, cell membrane, cell wall, ribosomes and cytoplasm. You observe no other organelles. The cell can be classified as...

Prokaryotic, because prokaryotic cells have all those organelles.

Most burgers are sold on Thursday because they were having a sale on burgers that day. This is an example of *

Reasoning

What are the steps in the signal transduction pathway?

Reception, transduction, response

When a car pulled in the driveway, my dog started barking. This is an example of what characteristic of life?

Response to stimuli

Coined the term "cell" after viewing cork and had huge beef with Sir Isaac Newton. * Theodore Schwann Rudolf Virchow Anton van Leeuwenhoek Robert Hooke Matthias Schleiden

Robert Hooke

Proved that cells come from existing cells. Theodore Schwann Rudolf Virchow Anton van Leeuwenhoek Robert Hooke Matthias Schleiden

Rudolf Virchow

Which statement best describes a direct result of damage to a phospholipid bilayer? * The balance of ions inside a cell will be disrupted and proteins could leak out because the phospholipid bilayer forms the cell membrane. Energy storage will be disrupted because the phospholipid bilayer is responsible for storing energy in the body. Chemical messages could not be sent to different parts of the body because the phospholipid bilayer forms hormones. A person would be vulnerable to disease because the phospholipid bilayer helps to fight infections in the body.

The balance of ions inside a cell will be disrupted and proteins could leak out because the phospholipid bilayer forms the cell membrane.

If you observe a cell and it does not have lysosomes, what might be a side effect of that for the cell?

The cell would not be able to break down and detoxify poisons.

Which one of the following is a scientific reasoning statement? *

The egg wrapped in bubble wrap did not break because the force was applied over a longer period of time.

how are charges distributed on a water molecule?

The oxygen end is negative relative to the end with the two hydrogens.

You are observing a slide of red blood cells with a compound microscope. (RBC's have about 1% solutes) What will happen to the RBC's on the slide if you add a drop of 5% NaCl (salt) solution to the slide to keep the cells from drying out?

The red blood cells will shrivel up.

Stated that animals are made of cells. Theodore Schwann Rudolf Virchow Anton van Leeuwenhoek Robert Hooke Matthias Schleiden

Theodore Schwann

Why are functional groups significant to a molecule?

They affect the shape of a molecule, it's properties, and how it functions.

If the molecules in a cell are in equilibrium, which way will the molecules move?

They will move across the cell membrane in both directions equally.

If you observe a cell without mitochondria, what would you expect the cell to not be able to do?

Transferring energy from glucose to ATP

Which of the following supports a claim that a virus may NOT be alive? *

Viruses are not made of cells and must rely on a host cell to be able to multiply.

Which of the following support a claim that a virus may be alive? *

Viruses have found ways to make new viruses by inserting their genetic material into a host cell.

A cell model containing 90% water, enclosed in a selectively permeable membrane, has just been put in a beaker with a solution that is 70% water. The membrane allows water and glucose to pass through, but won't let salt through. Which substance(s) will have a net movement OUT of the cell?

Water

If the concentration of a sugar solution is lower outside the cell than inside the cell, which of the following will happen by osmosis?

Water will move into the cell.

What problem is faced by organisms that live in fresh water?

Without compensating mechanisms, their bodies tend to take in too much water.

The contractile vacuole of a paramecium should be more active when the paramecium is in

a hypotonic environment

What is a polar molecule?

a molecule with opposite charges at opposite ends, due to the sharing of electrons

Substrates bind to an enzyme's __________ site.

active

Water doesn't drip off of a pine needle because water is attracted to the surface of the needle.

adhesion

Water molecules sticking to a mirror's surface

adhesion

Water moves from the roots to the leaves of plants. Water molecules stick to the cell wall due to ________. Water molecules follow each other through the tissue due to ________. *

adhesion, cohesion

Carbon can form bonds in several different configurations. They are:double bonds. long, straight and/or branched chains. carbon rings. all of the above.

all of the above

Eukaryotes usually contain * a nucleus. specialized organelles. genetic material. all of these answers apply.

all of these answers apply.

Prokaryotic and eukaryotic cells BOTH have the following organelle(s): * cell membrane cytoplasm ribosome all of these are in both prokaryotic and eukaryotic cells

all of these are in both prokaryotic and eukaryotic cells

Organic compounds

always contain carbon.

what functional group is H2N?

amino

Which of the following contains a carboxyl and an amino group? * amino acid fat sugar vinegar

amino acid

what is the monomer of a protein

amino acid

Glucose molecules are to starch as ________ are to proteins.

amino acids

Which of the following is an example of secondary structure in a protein? a particular amino acid sequence an alpha helix a globular shape the joining of two polypeptide chains

an alpha helix

Diffusion is the movement of molecules from

an area of high concentration to an area of low concentration.

Which of the following would be correctly classified as a protein?

an enzyme

The end result of a cell signaling pathway could be the following: * the activation of an enzyme the activation of a gene changes in the cytoskeleton any of these answers can occur as the result of a cell signaling pathway

any of these answers can occur as the result of a cell signaling pathway

Water passes through the cell membrane using,

aquaporins, a membrane spanning protein.

Sodium chloride (NaCl or salt) dissolves in water because water molecules _______.

are polar.

Cells called macrophages in the immune system send a ligand signal (Interlukin-1). Macrophages secreting Interlukin-1 also contain receptors for Interlukin-1, and the resulting feedback loop causes the immune response of swelling. This type of signaling is called

autocrine

Communication between two different cells can occur by all of the following mechanisms except

autocrine

What is being regulated in the insulin/glucagon feedback loop? What are we trying to keep in homeostasis?

blood glucose

You are given 4 test tubes containing purified biological macromolecules. The test tubes are unlabeled except for a number between 1 and 4. You are told that one test tube contains protein, one contains a lipid, one contains a carbohydrate, and one contains a nucleic acid. You then perform some tests on the macromolecules and collect the following information:Test tube # 2 and #4 contain nitrogen, but the other tubes do not.The contents of test tube #3 are not soluble in water, but the contents of the other test tubes are soluble in water.The contents of test tube # 1 can be broken down into subunits that are all exactly identical to each otherThe macromolecule in test tube #2 is found to have a globular shape. The contents of Test Tube #1 is (are)

carbohydrate

You identify a molecule in a pizza that is a polymer; has carbon, hydrogen, and oxygen atoms; and is hydrophilic. What kind of molecule is it?

carbohydrate

Which of the following organic compounds is the main source of energy for living things? *

carbohydrates

what functional group is c=o?

carbonyl

what functional group double bonds to c=o and c-ch

carboxyl

How do our cells use the glucose that is removed from our bloodstream?

change into ATP for energy

Heating inactivates enzymes by

changing the enzyme's three-dimensional shape.

Water falls from clouds in the form of droplets because of

cohesion

Water molecules form a bubble on the surface of a penny from sticking to one another.

cohesion

________________comes from hydrogen bonds that cause water molecules to stick together.

cohesion

The build up of molecules on one side of a membrane resulting in a high concentration of molecules on one side of the membrane and a low concentration of molecules on the other side of the membrane results in the formation of a(n)

concentration gradient.

A(n) ______ forms when two atoms share electrons.

covalent bond

The hydrogen atoms of a water molecule are bonded to the oxygen atom by _____ bonds, whereas neighboring water molecules are held together with other water molecules by _______ bonds.

covalent; hydrogen

A dipeptide is broken down into 2 separate amino acids. The enzyme that would help in this reaction would be called

dipeptase

You work for a company that manufactures food products. A new "wonder food" is being distributed by a rival company. The researchers in your company determine that the "wonder food" contains only carbon, oxygen, and hydrogen. At this point, your researchers can say with certainty that the food

does not include proteins or nucleic acids.

What are valance electrons?

electrons in the outermost level of an atom which are involved in bonding.

What type of cell signaling is taking place in the insulin/glucagon feedback loop?

endocrine

A eukaryotic cell has no nucleus or membrane bound organelles. True False

false

An example of a prokaryotic cell is a plant cell. true or false

false

Which of the following foods would be least likely to contribute to the development of coronary heart disease? lard/crisco butter bacon fish oil

fish oil

Which of the following organisms contain the polysaccharide chitin? * animals and plants plants and bacteria fungi and insects insects and plants

fungi and insects

what are the monomers of lipids?

glycerol and fatty acids

The storage form of carbohydrates is ________ in animals and ________ in plants.

glycogen; starch

A tadpole changes into a frog. This is an example of *

growth and development

what are the bonds that connect one water molecule to another?

hydrogen bond

if you are looking at a water molecule what are the TWO small molecules?

hydrogens

The results of dehydration synthesis can be reversed by

hydrolysis.

The presence of a phosphate group on a lipid molecule makes that portion of the molecule ____.

hydrophilic

a molecule with CH3´s would be hydrophobic hydrophilic

hydrophobic

Fatty acids are hydrophobic hydrophilic

hydrophobic.

what functional group is OH

hydroxide

A cucumber is placed into a solution of sugar, salt and vinegar. The slices get smaller. The solution of sugar, salt and vinegar is

hypertonic

Water moves into a cell placed in a(n) __?__ solution

hypotonic

You are rushed to the ER for dehydration. The nurse starts an IV to push fluids back into your system. The contents of that IV is likely to be, hypotonic to your cells so water will enter and rehydrate resulting in lysis. hypertonic to your cells so water will enter and rehydrate you resulting in crenation. hypotonic to your cells so water will rush into your cells and you will feel better faster. isotonic to your cells so water will begin to rebalance itself and bring your cells back to equillibrium.

isotonic to your cells so water will begin to rebalance itself and bring your cells back to equillibrium.

Glucose links with a galactose to form lactose and water. The enzyme that would help this reaction

lactose synthase

You are given 4 test tubes containing purified biological macromolecules. The test tubes are unlabeled except for a number between 1 and 4. You are told that one test tube contains protein, one contains a lipid, one contains a carbohydrate, and one contains a nucleic acid. You then perform some tests on the macromolecules and collect the following information:Test tube # 2 and #4 contain nitrogen, but the other tubes do not.The contents of test tube #3 are not soluble in water, but the contents of the other test tubes are soluble in water.The contents of test tube # 1 can be broken down into subunits that are all exactly identical to each otherThe macromolecule in test tube #2 is found to have a globular shape. The contents of Test Tube #3 is (are):

lipid

The hormone glucagon is released when blood glucose levels are ________ and functions to _________.

low, breakdown glycogen into glucose monomers

What functional group is CH3?

methyl

Complex carbohydrates are to monosaccharides as polymers are to

monomers

Amino acid is to protein as

monosaccharide is to starch.

what is the monomer that makes up carbohydrates?

monosacharides

Demonstrating their ability to adapt, viruses can

mutate and change the shape of protein receptors

What type of feedback is displayed in the insulin/glucagon feedback loop?

negative

You are given 4 test tubes containing purified biological macromolecules. The test tubes are unlabeled except for a number between 1 and 4. You are told that one test tube contains protein, one contains a lipid, one contains a carbohydrate, and one contains a nucleic acid. You then perform some tests on the macromolecules and collect the following information:Test tube # 2 and #4 contain nitrogen, but the other tubes do not.The contents of test tube #3 are not soluble in water, but the contents of the other test tubes are soluble in water.The contents of test tube # 1 can be broken down into subunits that are all exactly identical to each otherThe macromolecule in test tube #2 is found to have a globular shape. The contents of Test Tube #4 is (are):

nucleic acid

what is the monomer of nucleic acids

nucleotide

A water strider can skate along the top of a pond because

of the high surface tension of water.

A hydrogen atom has one electron. How many covalent bonds can hydrogen form? *

one

Ionic bonds form when _________. *

one atom transfers an electron to another atom. (gaining or losing of electrons)

A triglyceride is composed of

one glycerol molecule linked to three fatty acids.

If a cell is placed in salt water, water leaves the cell by:

osmosis

in a water molecule what is the One big molecule?

oxygen

any of these answers can occur as the result of a cell signaling pathway

paracrine

When 2 amino acids combine, the bond is called a(n)

peptide bond

what functional group has a a P in it?

phosphate

what are the bonds that hold a hydrogen to an oxygen molecule in a water molecule?

polar covalent bonds

You are given 4 test tubes containing purified biological macromolecules. The test tubes are unlabeled except for a number between 1 and 4. You are told that one test tube contains protein, one contains a lipid, one contains a carbohydrate, and one contains a nucleic acid. You then perform some tests on the macromolecules and collect the following information:Test tube # 2 and #4 contain nitrogen, but the other tubes do not.The contents of test tube #3 are not soluble in water, but the contents of the other test tubes are soluble in water.The contents of test tube # 1 can be broken down into subunits that are all exactly identical to each otherThe macromolecule in test tube #2 is found to have a globular shape. The contents of Test Tube #2 is (are):

protein

Which of the following particles are found in the nucleus of an atom?

protons and neutrons

Located on or within the cell are ___________ proteins, each of which has a three-dimensional shape complementary to that of a specific molecule. These proteins are responsible for receiving signals from other cells.

receptor

Shivering when you get too cold is an example of _________________

response to stimuli

A cell's contents would be the same as its surroundings, were it not for:

selective permeability

Regulating the passage of some substances while preventing others is referred to as ________________. This occurs in the _______________ (organelle).

selectively permeable, cell membrane

SOLUTE MOLECULES from which solution would be most likely to diffuse into the cell? the cell is 40% solution A:80 solution B:40 solution C:5 solution D :0

solution A:80

Which of the following substances is made of lipids?

steroids

Which of the following is NOT a function of proteins? * store and transmit hereditary information help to fight disease control the rate of reactions and regulate cell processes build tissues such as bone and muscle

store and transmit hereditary information

A protein's ________ determines its ____________.

structure, function

what functional group is SH?

sulfahydryl

The primary structure of a protein is

the amino acid sequence of the polypeptide chain.

The idea that all living things are composed of cells, that all cells come from other cells and that cells are the basic unit of structure and function defines

the cell theory.

Amino acids can be distinguished from one another by

the chemical properties of their R groups.

The tertiary structure of a polypeptide refers to

the overall three-dimensional structure..the polypeptide is folded in on itself

What "drives" the process of diffusion

the presence of a concentration gradient

The active site of an enzyme is

the region of an enzyme that attaches to a substrate

Proteins differ from one another because

the sequence of amino acids in the polypeptide chain differs from protein to protein

What is the general function of enzymes within a cell?

to speed up chemical reactions by lowering the activation energy required for the reaction to proceed from reactants to products.

Applying a hypertonic solution will reduce inflammation (swelling). True False

true

Bacteria are prokaryotic.true or false

true

Eukaryotic cells have DNA. true or false

true

Prokaryotic cells have DNA. true or false

true

Small, lipid soluble molecules can pass through a cell membrane. * True False

true

You can kill a plant by spraying it with a hypertonic solution. * True False

true

Fatty acids with double bonds between some of their carbons are said to be unsaturated. saturated.

unsaturated.

Which of the following substances passes through the cell membrane through the process of osmosis?

water

Lysozyme is an enzyme that breaks down bacterial cell walls and is found in your tears, mucus, and saliva. A mutation occurs in the gene for lysozyme that results in a lysine (a positively charged amino acid) being substituted for an arginine (also a positively charged amino acid). Do you think that the mutant lysozyme will function similarly to the normal lysozyme?

yes, because both lysine and arginine are positively charged so the tertiary structure and therefore function should be similar


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