Bio test 1

Identify the signaling process that stimulates a response by secreting signaling molecules that bind to receptors on the cell's own surface. Autocrine signaling Paracrine signaling Endocrine signaling

Autocrine signaling

Select all that apply What are the three domains of life? Multiple select question. Bacteria Archaea Animalia Eukarya Plantae Viruses

Bacteria Archaea Eukarya

Atoms tend to be most stable when their outer shells are (Blank); this can be accomplished by gaining, losing, or sharing (Blank)

Blank 1: filled or full Blank 2: electrons or valence electrons

Atoms tend to be most stable when their outer shells are (Blank); this can be accomplished by gaining, losing, or sharing (Blank).

Blank 1: full Blank 2: electrons

Ionic bond

Bond between a cation and an anion

hydrophobic effect

Interaction between nonpolar amino acids

Extraterrestrial Hypothesis

Meteorites brought organic carbon to Earth

A synonym for programmed cell death is

apoptosis

The genetic material of a eukaryotic cell is housed in the: nucleus Golgi apparatus peroxisome chloroplast

nucleus

Hydrogen bonds can form

within a polypeptide and between different polypeptide chains

Select all of the following that are functions of membrane proteins. Cell signaling Cell recognition Cell movement Energy transduction Transport

-Energy transduction -Cell Signaling -Cell Recognition -Transport

Where would peripheral (or extrinsic) membrane proteins likely reside with respect to the plasma membrane? On the outside of the inner leaflet, facing the cytoplasm On the outside of the outer leaflet, facing the outside of the cell Embedded within the interior of the plasma membrane

-on the outside of the inner leaflet, facing the cytoplasm -on the outside of the outer leaflet, facing the outside of the cell

Select the reasons why it is more appropriate to describe membranes as semifluid. Phospholipids usually move in two dimensions. Molecules move laterally within the membrane leaflet. Membrane proteins and lipids move freely in three dimensions. Phospholipids spontaneously migrate between leaflets.

-phospholipids usually move in two dimensions -molecules move laterally within the membrane leaflet

Cell-to-cell communication can occur via different mechanisms. In 1.____ signaling, a cell can respond to its own signal. In 2.____ signaling, a secreted signaling molecule affects nearby target cells but not the cell that secreted the signal. In 3.____ signaling, the signaling molecule can affect cells at a distance from the cell that secreted the signal.

1. autocrine 2. paracrine 3. endocrine

Each change of one pH unit represents a ______ difference in H+ concentrations. 10-fold 1-fold 100-fold 50-fold 2-fold

10-fold

In mammals, collagen is the most prevalent protein, making up what percentage of the total protein mass? 10% 50% 75% 25%

25%

How many covalent bonds can a carbon atom form with other atoms?

4

What is the normal pH range of living cells? 10.0-12.0 8.2-9.5 6.5-7.8 1.0-2.0

6.5-7.8

What is a tissue? A group of similar cells that are associated with one another The smallest unit of an element A group of organisms belonging to the same species A membrane-bounded compartment that is the smallest unit of life

A group of similar cells that are associated with one another

During cellular signaling, what event causes the receptor to become activated? The cytoskeleton of the cell is rearranged. Its gene is activated, which leads to synthesis of the receptor protein. A signaling molecule binds to it. A signal transduction pathway causes changes in the receptor.

A signaling molecule binds to it.

Which of the following solutions contains the highest concentration of protons? A solution with pH 5.0 A solution with pH 7.0 A solution with pH 2.0 A solution with pH 10.0

A solution with pH 2.0 Reason: The higher the pH value, the lower the concentration of protons.

Fats consist of three fatty _______ covalently bonded to a three-carbon molecule called _______.

Acids; Glycerol

Which of these statements is not a part of the cell theory? Cells are the smallest units of life. New cells come only from pre-existing cells by cell division. All cells are replaced. All living organisms are composed of one or more cells.

All cells are replaced.

Identify the three parts of the cell theory. All living organisms are composed of one or more cells. Cells are the largest units of life. New cells come only from pre-existing cells by cell division. Cells are the smallest units of life.

All living organisms are composed of one or more cells. New cells come only from pre-existing cells by cell division. Cells are the smallest units of life.

What type of organic molecule is shown in this diagram?

Amino acid

What is a community? . The interaction between a group of species and their physical environment A group of organisms of the same species that occupy the same environment An assemblage of populations of different species A group of macromolecules surrounded by a membrane

An assemblage of populations of different species

Cellular response

An enzyme, structural protein, or transcription factor is altered.

What allows animals to synthesize many different types of collagen proteins? Animals have a single collagen gene, but the protein is modified in many different ways after it is synthesized. Animals have many different genes that encode collagen polypeptides. Animals have a single collagen gene, but it mutates more often than most genes do.

Animals have many different genes that encode collagen polypeptides.

What is another name for programmed cell death? Apoptosis Cell communication Cell signaling Necrosis

Apoptosis

Why is the phospholipid bilayer an effective barrier to hydrophilic or polar molecules? Because most hydrophilic or polar molecules are large Because of the hydrophilic exterior of the bilayer Because of the polar head groups of phospholipids Because of the hydrophobic interior of the bilayer

Because of the hydrophobic interior of the bilayer

Why are atoms likely to share electrons? Because they have unfilled outer valence shells. Because they are considered an isotope. Because they are considered a noble gas. Because they have a high electronegativity. Because they contain seven or fewer total electrons.

Because they have unfilled outer valence shells.

In animals, what buffer is primarily responsible for maintaining the pH of body fluids? Citric acid Bicarbonate Ammonia Hydrochloric acid

Bicarbonate

Put the steps involved in a cell-to-cell signaling pathway in the correct order. Instructions

Binding of a signaling molecule to a receptor, intracellular signal transduction pathway, cellular response

BLank stores genetic information, Blank acts as an intermediary in protein synthesis, and proteins form the foundation for the structure and activities of living cells.

Blank 1: DNA Blank 2: RNA

Ions with a net negative charge are known as (Blank) whereas ions with a net positive charge are defined as (Blank)

Blank 1: anions Blank 2: cations

An ionic bond forms when a positively charged ion, called a(n) (Blank 1) interacts with a negatively charged ion, called a(n) (Blank 2)

Blank 1: cation Blank 2: anion

A DNA molecule consists of two strands coiled around each other to form a structure called a(n)

Blank 1: double Blank 2: helix

Antioxidants provide protection from free radicals because they can donate (Blank) to the free radicals without becoming highly reactive.

Blank 1: electrons

A(n) (Blank) containing an atom with a single, unpaired electron in its outer shell is known as a free radical.

Blank 1: molecule

Amphipathic molecules have both (Blank) regions and (Blank) regions.

Blank 1: polar or hydrophilic Blank 2: nonpolar or hydrophobic

The two most prevalent types of macromolecules in the extracellular matrix of animals are (blank) and (blank)

Blank 1: proteins Blank 2: polysaccharides

Atoms contain three types of particles, positively charged (Blank), negatively charged (Blank), and uncharged (Blank).

Blank 1: protons Blank 2: electrons Blank 3: neutrons

A solution at pH 6 is more acidic than a solution at pH 7 because the concentration of H+ (protons) is (Blank) times higher than that in a solution at pH 7.

Blank 1: ten

The of (blank) life includes only vertical descent, but the (blank) of life includes both vertical descent and horizontal gene transfer.

Blank 1: tree Blank 2: web

The two mechanisms that lead to evolutionary change are (blank) descent with modification/mutation and (blank) gene transfer.

Blank 1: vertical Blank 2: horizontal

Hydrogen bond

Bond between atoms with partial positive and partial negative charges

ionic bond

Bond between oppositely charged amino acid side chains

hydrogen bond

Bond between partial positive and negative charges on different amino acids

Select all the functions of anchoring junctions. Bond cells to the extracellular matrix Anchor ER membranes of adjacent cells to each other Provide a passageway for intercellular transport Attach cells to each other

Bond cells to the extracellular matrix Attach cells to each other

Nonpolar covalent bond

Bond in which two atoms share electrons equally

Polar covalent bond

Bond in which two atoms share electrons unequally

What do enzyme-linked receptors and growth factor receptors have in common? Both seldom affect the expression of genes within the nucleus. Both regulate the transport of ions through channels. Both act as transcriptional factors. Both possess kinase activity when bound to a hormone. Both regulate specific G proteins when bound to a hormone.

Both possess kinase activity when bound to a hormone.

What is the function of the lysosome?

Breakdown of macromolecules

Which of these is the study of individual cells and their interactions with each other? Microbiology Cell biology Ecology

Cell biology

What best explains why most cells are small? Cells must start small so they can grow larger Cells must be small in order to move around Cells must be small to be able to take up nutrients efficiently.

Cells must be small to be able to take up nutrients efficiently.

The membranes of the endoplasmic reticulum form which of the following? Cylindrical tubules Ribosome subunits Cisternae Fluid-filled tubules

Cisternae Fluid-filled tubules

Which of the following were formed during the second stage in the origin of life? Simple organic molecules Complex living cells Complex organic polymers Simple living cells

Complex organic polymers

Which signaling mechanism involves an interaction between a membrane-bound signaling molecule on one cell and a receptor on the surface of another cell? Autocrine signaling Contact-dependent signaling Direct intercellular signaling Paracrine signaling Endocrine signaling

Contact-dependent signaling

Which type of cell-to-cell communication involves signaling molecules that do not diffuse readily from one cell to another? Paracrine signaling Direct intercellular signaling Contact-dependent signaling

Contact-dependent signaling

disulfide bond

Covalent bond between two cysteines

Which of the following serves as the genetic material of all living things? DNA RNA Carbohydrates Protein

DNA

What is osmosis?

Diffusion of water from an area of low solute concentration to an area of high solute concentration

What type of signaling involves signals that pass through a cell junction from the cytosol of one cell to the cytosol of an adjacent cell? Intracellular signaling Autocrine signaling Direct intercellular signaling Contact-dependent signaling

Direct intercellular signaling

The process of collecting and analyzing data without a preconceived hypothesis is referred to as (blank)-based science.

Discovery

What level of organization is formed by interactions of a community of organisms with their physical environment? Species Organism Population Ecosystem

Ecosystem

Which of the following statements (2) are true of a nonpolar covalent bond? Electrons are shared equally between the two atoms. One or more electrons is transferred from one atom to the other. The shared electrons are closer to one nucleus than to the other. The two atoms have similar electronegativity values.

Electrons are shared equally between the two atoms. The two atoms have similar electronegativity values.

Which of the following mechanisms help organisms to regulate their internal pH? (select more then one) Evaporation Elimination of H+ in urine (via the kidneys). Buffers

Elimination of H+ in urine (via the kidneys). Buffers

Which type of signaling mechanism occurs between cells at a great distance from one another? Contact-dependent Endocrine Paracrine Autocrine Direct intercellular

Endocrine

What type of cell-to-cell communication is shown in this figure? Autocrine signaling Contact-dependent signaling Direct intercellular signaling Endocrine signaling Paracrine signaling

Endocrine signaling

Which signaling process occurs when cells release signals that travel long distances to affect target cells? Autocrine signaling Endocrine signaling Paracrine signaling Synaptic signaling

Endocrine signaling

Which of the following are examples of cell-to-cell signaling? Multiple select question. Differential gene signaling Endocrine signaling Direct intercellular signaling Paracrine signaling Contact-dependent signaling

Endocrine signaling Direct intercellular signaling Paracrine signaling Contact-dependent signaling

What characteristic of living organisms explains both the unity and diversity of modern species? Transcription Homeostasis Populations Evolution

Evolution

Deep-Sea Vent Hypothesis

Extreme temperatures, metal ions, and H2S and NH3 interact, leading to organic molecules

True or false: Collagen and elastin are structural proteins that both provide elasticity to the body parts in which they are found.

F

True or false: Molecules that contain covalent bonds are rigid, inflexible structures.

F

True or false: Vacuoles are prominent organelles in animal cells, and rarely found in plants cells.

False

True or false: Some living cells do not conduct and require cell communication to survive.

False For living cells to survive, they all need to communicate at the cellular level. This communication is also known as cell signaling.

Peroxisomes are involved in detoxification as well as the metabolism of amino acids and

Fats

How can fats provide protection for mammals in cold weather

Fats under the skin can provide insulation to protect against cold.

What property of biological membranes describes the ability of individual molecules to move within the membrane? Rigidity Permeability Mosaic composition Fluidity

Fluidity

Which of the following describes the chemical structure of steroids?

Four fused rings of carbon with one or more attached hydroxyl groups

Groups of atoms with characteristic chemical features and properties are called (blank) groups

Functional

The function of a chloroplast is to capture the light energy necessary for the synthesis of which of the following organic molecules in the process of photosynthesis.

Glucose

The processing (ie: modification), sorting and secretion of cellular molecules are carried out by an organelle in the cell called the

Golgi apparatus

What are functional groups?

Groups of atoms with characteristic chemical features and properties

RNA contains which of the following? Guanine Adenine Uracil Cytosine Thymine Deoxyribose Ribose

Guanine Adenine Uracil Cytosine Ribose

In the bicarbonate pathway, the combining of carbon dioxide and water that produces carbonic acid can lower the pH because: H+ can be released O2 can be released OH- can be released CO2 can be released

H+ can be released

When the concentration of a ligand is equal to the KD which of the following is true? All of the ligands and receptors are bound to each other. All of the ligands are bound to receptors. All of the receptors are bound to ligands. Half of the receptors are bound to ligands. Half of the ligands are bound to receptors.

Half of the receptors are bound to ligands.

What is the function of the middle lamella in plants? Holds adjacent cell walls together Binds cells to the extracellular matrix Provides passageways for intercellular transport Prevents leakage of materials between cells

Holds adjacent cell walls together

What evolutionary mechanism has led to widespread antibiotic resistance among many species of bacteria? Multiple choice question. Homeostasis Heritability Vertical descent with mutation Horizontal gene transfer

Horizontal gene transfer

What type of gene transfer can occur between members of different species? Multiple choice question. Horizontal gene transfer Vertical gene transfer Natural selection Lineage transfer

Horizontal gene transfer

Select all that apply Which types of chemical bonds are easily broken in water? Hydrogen bonds Polar covalent bonds Ionic bonds Nonpolar covalent bonds

Hydrogen bonds Ionic bonds

In contact-dependent signaling, where is the signaling molecule located? In the bloodstream In the cytoplasm of a cell In the nucleus of a cell On the membrane of a cell

In the membrane of cell

Which of the following statements is correct about a biological membrane that is fluid? The composition of the membrane changes over short periods of time. The structure of the membrane is solid and rigid but dissolves readily. Individual molecules can move within the membrane. Individual molecules remain in static locations.

Individual molecules can move within the membrane

How would early cells benefit from DNA replacing RNA as the information storage molecule? DNA mutates more easily. RNA would have more flexibility in its catalytic functions. Information would be stored in a more stable molecule. RNA would serve a role only as mRNA.

Information would be stored in a more stable molecule. RNA would have more flexibility in its catalytic functions.

What type of bond forms when a cation with a positive charge interacts with an anion carrying a negative charge? Ionic Polar covalent Non-polar covalent van der Waals

Ionic

What is the main determinant of a protein's tertiary structure?

Its primary structure

Lipid-anchored proteins

Lipid tails are inserted into the hydrophobic portion of the membrane.

The three main types of macromolecules that comprise the plasma membrane are

Lipids, Carbohydrates, and proteins

Which state of water is the most dense? Multiple choice question. Gas Liquid Solid

Liquid

Acid hydrolases are found in which organelle? Mitochondria Endoplasmic reticulum Peroxisomes Golgi apparatus Lysosomes

Lysosomes

What is true of collagen in animals? Many different types are produced. All collagens have the same amino acid sequence. One type is produced and is nearly universal.

Many different types are produced.

What is true of collagen in animals? All collagens have the same amino acid sequence. One type is produced and is nearly universal. Many different types are produced.

Many different types are produced.

The organelle that is responsible for most of a cell's ATP production is the

Mitochondria

Which of the following are considered semiautonomous organelles?

Mitochondria Chloroplasts

Arrange these carbohydrates in order of increasing size, from smallest to largest, with the smallest at the top of the list. Monosaccharide Disaccharide Polysaccharide

Monosaccharide Disaccharide Polysaccharide (same order)

Match each type of carbohydrate with the number of sugar monomers it contains. Instructions

Monosaccharide-One monomer Disaccharide-Two monomers Polysaccharide-Many monomers

What type of monomers are combined to form carbohydrates?

Monosaccharides

Consider a mutation that alters an organism's traits so that it increases the likelihood of survival and reproduction of the organism. Such a mutation may become more common in the population over time due to a process called

Natural Selection

what charge dose a electron have?

Negative

Electron

Negatively charged, located outside the nucleus

What type of interaction occurs between a ligand and its receptor? Non-covalent and specific Covalent and specific Non-covalent and non-specific Covalent and non-specific

Non-covalent and specific

Peripheral membrane proteins

Not covalently bound to membrane

What type of organic molecule is shown in this given figure?

Nucleotide

List the stages of the origin of life

Nucleotides and amino acids were produced prior to cells Nucleotides became polarized to form DNA and rna and amino acids form proteins polymers get put into membranes in the membrane they get cell properties

Where is most of the DNA located in a eukaryotic cell? Ribosome Nucleus Cytoskeleton Golgi apparatus

Nucleus

What did Wohler and Kolbe's experiments demonstrate?

Organic compounds can be synthesized from inorganic compounds.

In what type of signaling does a specific cell produce a signaling molecule that does not affect the cell secreting the signal but influences the behavior of target cells in close proximity? Direct intercellular Paracrine Autocrine Endocrine

Paracrine

The five common ways cells communicate with each other are direct intercellular signaling, contact-dependent signaling, ____ signaling, ____ signaling, and ____ signaling.

Paracrine Autocrine Endocrine

Proteins that associate with the plasma membrane through non-covalent interactions with phospholipids or transmembrane proteins are called (blank) membrane proteins.

Peripheral

membrane proteins are non-covalently bound to the hydrophilic regions of integral membrane proteins or the polar head groups of lipids.

Peripheral

How are monomers and polymers related to one another?

Polymers are large macromolecules composed of many monomers linked together.

What type of organic molecule is shown in this illustration?

Polypeptide

When many monosaccharides are linked together, they form long carbohydrate polymers called

Polysaccharides

Proton

Positively charged, located in the nucleus

What is the precursor to collagen? Protocollagen Procollagen Elastin Gelatin

Procollagen

Which macromolecule forms the foundation for the structure and activities of living cells? DNA Protein RNA

Protein

Which of the following are the overlapping functions of the Golgi apparatus? Protein sorting Protein synthesis Protein secretion Protein processing

Protein sorting Protein secretion Protein processing

What do gap junctions do in animals? Prevent leakage of material between cells Provide passageways for intercellular transport Hold adjacent cells together Bind cells to the extracellular matrix

Provide passageways for intercellular transport

The macromolecule ______ can self-replicate, store information, and perform catalytic functions and may likely have been the first macromolecule to evolve. DNA phospholipid protein RNA

RNA

The interaction of which of the following macromolecules plays an important role in the formation of living cells? proteins RNA DNA carbohydrates

RNA proteins DNA

Nucleotides and amino acids were polymerized to form lipids and proteins carbohydrates and proteins RNA, DNA, and proteins

RNA, DNA, and Proteins

Which hypothesis regarding the origin of life on Earth suggests that oxidation-reduction (redox) reactions may be responsible for the formation of complex organic molecules from simple organic molecules? Deep Sea Vent Hypothesis Oxidizing Hypothesis Extraterrestrial Hypothesis Reducing Atmosphere Hypothesis

Reducing Atmosphere Hypothesis

Which levels of protein structure are stabilized by hydrogen bonds?

Secondary structure Tertiary structure Quaternary structure

Why do shorter tails make membranes more fluid? Shorter tails have more nonpolar character Shorter tails attract each other more strongly Shorter tails create clumps of lipids Shorter tails interact less with each other.

Shorter tails interact less with each other.

Cell communication, also called cell ______, involves both incoming and outgoing signals. apoptosis respiration signaling metabolism

Signaling

Cellular

Signals influence the behavior of cells by interacting with the receptors to elicit what type of response?

True or false: Evolutionary changes frequently involve the modification of pre-existing structures for a new function.

T

The structure of the different types of collagen proteins and resulting collagen fibers is affected by:

The amino acid sequence

What determines the types of species found in a community? Select all that apply. The environment The degree of genetic similarity among the species Interactions among different species

The environment Interactions among different species

What separates the internal contents of a cell from the extracellular environment? The nuclear envelope The plasma membrane The nucleus The extracellular matrix

The plasma membrane

Which regions of a phospholipid bilayer face water and which face the interior of the membrane away from water

The polar regions face water, and the nonpolar regions face the interior.

Estrogen is a lipid soluble hormone that can easily cross membranes. Knowing this, what can be concluded about estrogen receptors? The receptors would be found inside the cell. The receptors would be coupled to a G-protein. The receptors would be linked to enzymes that triggered a kinase cascade. The receptors would be on the plasma membrane. The receptors would also be lipid soluble and able to cross membranes.

The receptors would be found inside the cell.

Which of the following statements is true of a polar covalent bond? The two atoms have similar electronegativity values. Electrons are shared equally between the two atoms. The shared electrons are closer to one nucleus than to the other. One or more electrons is transferred from one atom to the other.

The shared electrons are closer to one nucleus than to the other. Reason: In a polar covalent bond, electrons are shared unequally between the two atoms in the bond.

Signal transduction

The signal is converted to a different type of signal, often resulting in the production of an intracellular signaling molecule.

Patients who have type 2 diabetes no longer respond normally to insulin. Which statement best explains this symptom? Their cells express less insulin receptor. The insulin receptors on their cells have mutated. The nucleus of their cells are altered so that insulin can not bind. The signal transduction pathways in the cells no longer exist. Type 2 diabetics do not produce insulin.

Their cells express less insulin receptor.

Atoms are chemically the most stable when which of the following occurs?

Their outer shell is full.

desmosomes

These act as rivets anchoring adjacent cells together at spots throughout the cell.

How do adhesive proteins work? They are able to connect to receptors on the surfaces of cells. They form large fibers, giving the extracellular matrix its strength and elasticity. They have sites that bind to polysaccharides and proteins in the extracellular matrix. They form many covalent cross-links, allowing the protein to expand and return to its original shape.

They are able to connect to receptors on the surfaces of cells they have sites that bind to polysaccharides and proteins in the extracellular matrix

Which of the following statements describe hydrophilic molecules? They contain many nonpolar covalent bonds. They are uncharged. They are soluble in water. They are smaller than hydrophobic molecules.

They are soluble in water.

What are the distance requirements for cells to communicate with one another through endocrine signaling? They may be distant from one another. They must be in contact with one another. They must be near each other but do not have to be in contact with each other.

They may be distant from one another.

Which of the following structures prevent material from passing in between adjacent cells of animals. Plasmodesmata Anchoring junctions Tight junctions Gap junctions

Tight junctions

Why do micelles form? To minimize interactions of nonpolar regions of molecules with water. To minimize interactions of charged regions of molecules with water. To minimize interactions of polar regions of molecules with water.

To minimize interactions of nonpolar regions of molecules with water.

Which of the following is the main function of collagen? To provide tensile strength to the extracellular matrix. To connect cells to the extracellular matrix. To provide elasticity to the extracellular matrix. To organize components of the extracellular matrix.

To provide tensile strength to the extracellular matrix.

Regions inserted into the hydrophobic interior are usually α helices.

Transmembrane proteins

True or false: The mode of communication between two cells depends in part on the distance between the cells.

True Cells that are adjacent to one another communicate through paracrine signaling and contact-dependent signaling. Cells that are far away from one another communicate using hormones.

Neutron

Uncharged, located in the nucleus

Which type of gene transfer is more common, vertical transfer or horizontal transfer? They are equally common Horizontal transfer Vertical transfer

Vertical transfer

Reducing Atmosphere Hypothesis

Water vapor, hydrogen gas, methane, and ammonia interact in the absence of oxygen to produce organic molecules

A long hydrocarbon chain resembling a fatty acid attached by its carboxyl group to another long hydrocarbon chain is best described as a

Wax

What type of lipid consists of long structures resembling fatty acids attached to each other by their carboxyl groups?

Wax

van der Waals force

Weak, temporary attraction between two atoms

What is the basic structure of the plasma membrane?

a phospholipid bilayer

A hypothesis is Multiple choice question. a best guess. an explanation for a natural phenomenon that is backed by extensive evidence. a proposed explanation for a natural phenomenon.

a proposed explanation for a natural phenomenon.

The structure of a typical collagen protein is: repeating glucose units linked end to end a triple helix of polypeptides many polysaccharides connected to a core protein many proteins connected via covalent cross-links

a triple helix of polypeptides

A solution at pH 5 is said to be ______ because it contains more ______. basic; OH- ions than H+ ions acidic; H+ ions than OH- ions basic; H+ ions than OH- ions acidic; OH- ions than H+ ions

acidic; H+ ions than OH- ions

With respect to pH, blood in the human body is within a narrow range of values that are considered to be slightly: acidic oxygenated alkaline unstable

alkaline

Most transmembrane segments of integral membrane proteins are folded into what type of secondary structure? alpha-helix globular beta-pleated sheet a bilayer

alpha-helix

The structure of a collagen protein and fibers is affected by the sequence of

amino acids

Some anticancer drugs block signal transduction pathways activated by growth factors. Which of the following would be a good target for such a drug? an inhibitor of adenylyl cyclase an inhibitor of a protein kinase cascade an inhibitor of Ca2+ release an inhibitor of phospholipase C a phosphatase inhibitor

an inhibitor of a protein kinase cascade

In a developing human embryo, the hands and feet resemble mittens, with cells and tissues present between the fingers and toes. When a baby is born, these cells are not present, resulting in distinct fingers and toes. In the development of fingers and toes these cells were lost by cell morphology. apoptosis. cell division. cell connections.

apoptosis.

Molecules with covalent bonds: are flexible within certain limits cannot change shape without breaking covalent bonds are rigid at all times

are flexible within certain limits

All matter is composed

atoms

In (blank) signaling, a cell secretes signaling molecules that bind to receptors on its own cell surface, stimulating a cellular response.

autocrine

In ______ signaling, the same cell that secretes a signaling molecule responds to it. autocrine direct intercellular contact-dependent endocrine paracrine

autocrine

Which of the following types of organisms have cells that are surrounded by a cell wall that provides structure and support? Fungi Plants Animals Archaea Bacteria

bacteria archaea fungi plants

The (blank) includes all the regions on the surface of the Earth and in the atmosphere where living organisms exist.

biosphere

The types of species found in a community are influenced by interactions among the species, but not the environment. both the environment and interactions among the species. the environment, but not interactions among the species. neither the environment nor interactions among the species.

both the environment and interactions among the species.

Proteins are a major component of the extracellular matrix in animals. The second major molecular component are (Blank)

carbohydrates

What are the four categories of macromolecules?

carbohydrates, lipids, proteins, nucleic acids

What are the three molecular components of cellular membranes? nucleic acids phospholipids carbohydrates proteins minerals

carbohydrates, proteins, phospholipids

Lipids are molecules that are composed of primarily what two elements?

carbon hydrogen

Which elements are the primary components of lipids?

carbon and hydrogen

The three chemical elements that are found in all carbohydrates are

carbon, hydrogen, and oxygen

What process requires gap junctions? Contraction of cardiac muscle cells Transport of materials between the intestine and the blood Adhesion of cells during embryonic development

cardiac mucsle contraction

A simple unit of life surrounded by a membrane that contains macromolecules and molecules associated with each other is called a species. tissue. cell. population.

cell

A key component of anchoring junctions are proteins called CAMs, which stands for (blank)

cell adhesion molecules

In plants and animals, cells are linked to one another by: cell connections cell attachments cell walls cell junctions

cell junctions

The level of biological organization studied by cell biologists is the (blank).

cell level

Schwann and Schleiden are credited with: genetic code discovery cell theory endosymbiotic theory theory of evolution

cell theory

Signals influence the behavior of _____ nearby or at long distances by interacting with receptors to elicit a response.

cells

Cell signaling is important because: all cells undergo phototropism. cells need to communicate with each other. a low level of apoptosis must be ensured. cells need to respond to a changing environment.

cells need to communicate with each other. cells need to respond to a changing environment.

Isomers are molecules that have the same ______ but different ______ and characteristics.

chemical formula; structures

The semiautonomous organelles are the

chloroplasts and mitochondria

Although they are both structural, _________ provides tensile strength, whereas ________ provides elasticity to the body parts in which they are found

collagen elastin

An assemblage of populations of different species that live together in one place is a biological (blank).

community

Select all that apply molecules that only have hydrophobic regions. Multiple select question. contain many nonpolar covalent bonds form micelles when placed in water have atoms with partial positive and partial negative charges dissolve well in nonpolar solvents relatively insoluble in water

contain many nonpolar covalent bonds dissolve well in nonpolar solvents relatively insoluble in water

Which of the following descriptions apply typically to DNA?

contains deoxyribosecontains adenine and guaninestore genetic information in cells

Ice floats in liquid water because ice has a lower ______ than liquid water. heat of evaporation density molecular mass heat of fusion specific heat

density

The epithelial tissue of animal cells is most similar to the ________ of plant cells?

dermal

Select all of the following that describe molecules that only have hydrophobic regions. Multiple select question. have atoms with partial positive and partial negative charges form micelles when placed in water dissolve well in nonpolar solvents contain many nonpolar covalent bonds relatively insoluble in water

dissolve well in nonpolar solvents contain many nonpolar covalent bonds relatively insoluble in water

According to the octet rule, atoms are most stable when they have (Blank) electrons in their outermost shell.

eight

The ability of the lungs to expand and contract is due to fibers made of: fibronectin elastin laminin collagen

elastin

The ability of the lungs to expand and contract is due to fibers made of: laminin fibronectin collagen elastin

elastin

What protein, found in the extracellular matrix of animals, forms fibers and is abundant in regions that expand and contract, such as the lungs and blood vessels? tubulin elastin integrin keratin

elastin

Atoms are most stable when their outer shells are filled with

electrons.

Atoms are most stable when their outer shells are filled with neutrons. electrons. protons.

electrons.

The plasma membrane of eukaryotic cells is part of the endomembrane system nucleus cytosol Golgi apparatus

endomembrane system

Cell signaling allows cells to detect and respond to signals from their (blank) and from other cells.

environment

The unity of modern organisms can be explained by the realization that all livings things ______ an interrelated group of ancestors. Multiple choice question. gave rise to created evolved from caused the extinction of

evolved from

In animals, anchoring junctions attach adjacent cells to each other and to the

extracellular matrix

Blood vessels that can expand and contract contain a lot of collagen as a structural extracellular matrix protein. True or False

false

Cellulose in the cell wall is a primary energy store for plants. True or False

false

True or false: Most cells are visible to the naked eye.

false

True or false: The theory of endosymbiosis suggests that all membrane-bound organelles originated from bacteria that took up residence within a primordial eukaryotic cell.

false

Peroxisome enzymes perform a variety of functions including (answer all that apply) fat metabolism detoxification amino acid metabolism protein synthesis

fat metabolism detoxification amino acid metabolism

One of the principles exhibited by all forms of life is that structure determines ______, which applies to small molecules, macromolecules, and multicellular tissues and features.

function

You inject a dye into an animal cell and observe that it moves into adjacent cells. This would occur through plasmodesmata. adherens junctions. gap junctions. desmosomes. tight junctions.

gap junctions

In a mitochondrion, the chromosomes are known as the mitochondrial phenocopy. genotype. proteome. genome.

genome

The complete set of genetic material present in a cell or organism is called its proteome. genome. phenotype. gene. genotype.

genome

is defined as the entire complement of the genetic material of a species.

genome

Fats, or triglycerides, are composed of:

glycerol covalently bound to three fatty acids

The different chemical properties of amino acids have given proteins ______ catalytic ability than RNA molecules. greater lesser

greater

An amphipathic molecule: has non-polar regions is electrically neutral has polar regions dissolves completely in water

has non-polar regions has polar regions

All types of collagen have a common structure in which three polypeptides wind around one another to form a triple (Blank)

helix

Anchoring junctions are cell junctions that from between adjacent cells in a layer and prevent the leakage of materials between cells. consist of a collection of channels that permit the direct exchange of ions between the cytosol of adjacent cells. hold adjacent cells together or attach cells to the extracellular matrix.

hold adjacent cells together or attach cells to the extracellular matrix.

The considerable amount of heat it takes to boil water is due to the collective strength of many (Blank) bonds.

hydrogen or H

Phospholipids have a ________ head region that will interact with aqueous environments

hydrophilic

A mutation that ______ may confer a beneficial trait to a population of organisms, and eventually lead to evolution. is neutral and does not harm or benefit a species is detrimental to survival has no effect on survival increases survival and reproduction

increases survival and reproduction

Wohler and Kolbe demonstrated that organic compounds, such as urea and acetic acid, could be synthesize from:

inorganic compounds

Cellular receptors can be located: inside the cell in the human genome on the cell surface

inside the cell on the cell surface

A membrane protein that has a portion integrated into the hydrophobic region of the membrane is called a(n) ______ membrane protein. noncovalent peripheral integral locked

integral

Passage of (blank) through gap junctions allows the coordinated contraction of cardiac muscle cells.

ions

connective tissue

is rich in extracellular matrix.

Molecules that have identical molecular formulas but different structures are called functional groups. isotopes. reactants. isomers.

isomers.

Most phospholipids move freely within a semifluid membrane laterally along the plane of the membrane in two dimensions from the cytoplasmic to the outer face of a plasma membrane. in three dimensions

laterally along the plane of the membrane

When a(n) ___ binds to its receptor, it causes a conformational change in the receptor.

ligand

Select all the membrane proteins that are integral membrane proteins. lipid-anchored proteins noncovalent helix proteins peripheral membrane proteins transmembrane proteins

lipid-anchored proteins transmembrane proteins

Molecules involved in (blank)-distance signaling are called hormones.

long

In osmosis, water moves from areas of low solute concentration to areas of high solute concentration. high solute concentration to areas of low solute concentration.

low solute concentration to areas of high solute concentration.

The plasma (blank) separates the internal contents of a cell from the extracellular environment.

membrane

The endoplasmic reticulum (ER) is a network of

membranes

To understand how life originated on Earth, it is important to realize that after RNA or DNA was formed, these polymers were enclosed in membranes. mitochondria. cisternae. cytoskeletal fibers.

membranes.

are small molecules that are linked together to form polymers, such as proteins, polysaccharides, and nucleic acids.

monomers

What type of organic molecule can assume both a linear or ring form?

monosaccharide

Carbohydrate monomers are known as

monosaccharides

In vertical evolution, new species evolve from pre-existing species by accumulation of (blank) which are changes in the genetic message.

mutations

Random changes in the genetic material of an organism are called .

mutations

Genes that are transferred horizontally may promote changes in an entire species if they are subject to (blank) selection.

natural

What charge dose a neutron have?

no charge

A ligand binds ____ to its receptor with a high degree of specificity.

noncovalently

The transmembrane segments of integral membrane proteins are ______ and interact with the ______ of the phospholipid bilayer. nonpolar; hydrophobic tails nonpolar; hydrophilic heads polar; hydrophobic tails polar; hydrophilic heads

nonpolar; hydrophobic tails

The fatty acid tails of phospholipids are ______ and are found in the ______ of the phospholipid bilayer nonpolar; interior hydrophobic; exterior hydrophilic; interior polar; exterior

nonpolar; interior

The double membrane structure that surrounds the nucleus is the: plasma membrane nuclear envelope nuclear matrix

nuclear envelope

The organic molecule shown in this provided picture is a(n):

nucleotide

In eukaryotic cells, most of the DNA is housed in an internal compartment, or organelle, called the

nucleus

is an organelle in eukaryotic cells that contains most of the cell's genetic material.

nucleus

A protein whose highest level of structure is tertiary structure contains:

one polypeptide folded into its three-dimensional structure

The heart is a(n) ________ composed mainly of ________ tissue?

organ; muscle

Living things are also called ______, and a group of organisms with the same form and set of attributes is called a(n) ______. communities; ecosystem organisms; species molecules; macromolecule atoms; tissue

organisms; species

Virchow proposed that all cells: can only be multicellular originate from other cells originate only with oxygen originate spontaneously

originate from other cells

A free radical is a molecule containing an atom with a single unpaired electron in its: hydrogen bond innermost shell outer shell nucleus

outer shell

signaling, a cell secretes a signaling molecule that does not affect the cell secreting the signal but influences the behavior of target cells in close proximity.

paracrine

The plasma membrane consists of a(n) (Blank) bilayer

phospholipid

Cell surface receptors are receptors that are embedded in the:

plasma membrane

The boundary between any cell and its extracellular environment is the cytoplasm endoplasmic reticulum capsule cell wall plasma membrane

plasma membrane

What type of cell junctions form channels between adjacent plant cells? plasmodesmata desmosomes hemidesmosomes gap junctions

plasmodesmata

Carbohydrate polymers are called:

polysaccharides

A group of organisms of the same species that occupy the same environment is called a(n) .

population

what charge dose a proton have

positive

Ions are of two main types: cations which are ______, and anions which are ______. negatively-charged; positively-charged positively-charged; neutral positively-charged; negatively-charged negatively-charged; neutral neutral; positively-charged neutral; negatively-charged

positively-charged; negatively-charged

The amino acid sequence of a polypeptide is called the

primary

What component of a plant cell wall is synthesized first? secondary cell wall basement membrane primary cell wall extracellular matrix

primary cell wall

Match the level of protein organization with the proper description:

primary the linear sequence of amino acids secondary repetitive folding patterns such as α helix and β pleated sheet tertiary the three-dimensional structure of a polypeptide quaternary two or more interacting polypeptides

A triple helix molecule, called____, becomes collagen when its extension sequences are removed by extracellular enzymes following secretion from the cell.

procollagen

Based on cell structure, all life forms can be placed into two categories called

prokaryotes and eukaryotes

Movement of ions and large molecules into and out of the cell is mediated by membrane ______. steroids proteins carbohydrates phospholipids

proteins

The molecules that are most directly responsible for the structure and function of cells are: Multiple choice question. carbohydrates lipids sugars proteins

proteins

While DNA encodes the information for traits of organisms and cells,(blank) are the macromolecules that are directly responsible for the structure and function of cells.

proteins

All the proteins in a cell make up the proteome chromatin genome nucleolus

proteome

The complete protein composition of a cell or organism is called the

proteome

(blank) is an aggregate of prebiotically produced molecules and macromolecules with a boundary to separate its internal chemical environment from its surroundings.

protobiont

A collection of prebiotically produced molecules and macromolecules possessing a boundary which separates its internal and external environments is a: prokaryote protobiont protist

protobiont

Cellular signaling involves an interaction between a signaling molecule from one cell and a(n) __________ on or in another cell

receptor

The process of cell signaling consists of three stages: ___ activation, signal ____ , and a ___ response.

receptor, transduction, cellular

Proteins that interact with signaling molecules are called _____ . These proteins can be located on the cell surface or inside the cell.

receptors

What are the two possible shapes formed by monosaccharides such as glucose?

ring linear

The observation, identification, experimental investigation, and theoretical explanation of natural phenomenon can be defined as Multiple choice question. the gene theory. the hierarchy of life. science. an organism.

science.

Simple organic molecules polymerized to form complex organic polymers during the ______ stage in the origin of life. fourth third first second

second

The kidneys can help organisms cope with changes in pH by: Multiple select question. secreting acidic compounds into the bloodstream transferring hydrogen ions from the fluids of the body into the urine secreting alkaline compounds into the bloodstream participating in the regulation of blood pressure

secreting acidic compounds into the bloodstream transferring hydrogen ions from the fluids of the body into the urine secreting alkaline compounds into the bloodstream

All cells are surrounded by a(blank)permeable plasma membrane, meaning that the membrane allows the passage of some molecules and ions but not others.

selectively

Select all of the functions exhibited by RNA that may have led to it being the first macromolecule. self-replicate function as ribozymes perform photosynthesis store information

self-replicate, store information, function as ribozymes

Receptor activation

signaling molecule binds to receptor

The smallest entity that can be considered a living organism is the

single cell/ cell

The ability of a molecule to pass through gap junctions depends on the molecule's: net electrical charge hydrophilic or hydrophobic character size

size

Collagen is the main protein found in which of the following body parts? The lining of internal organs Skeletal muscle The brain Cartilage The lining of blood vessels Skin Tendons Bones

skin cartilage the lining of blood vessels bones tendons the lining of internal organs

Ions and molecules can pass through gap junctions only if the ions and molecules are: hydrophobic small enough hydrophilic large enough

small enough

An important part of science is the communication of results through journals and conferences and the peer-review process. These aspects of science make it a(n) ______ discipline. Multiple choice question. social self-reflective independent

social

Transmembrane proteins are able to span the hydrophobic portion of the bilayer because they have peripheral membrane proteins bound noncovalently, cross-linked glycolipids. stretches of nonpolar amino acids. lipid molecules covalently attached to the protein.

stretches of nonpolar amino acids.

Disulfide bridges are covalent bonds between (blank) groups of cysteine side chains.

sulfhydryl

What functional group is involved in disulfide bridges?

sulfhydryl

What are the functions of fats in living organisms?

support cushion for organs, insulation, energy storage

In contact-dependent signaling, the signaling molecule is bound to the ________ of one cell and is recognized by a receptor on another cell.

surface

The grouping of species for purposes of classification is called Multiple choice question. demography. taxonomy. genomics. paleontology.

taxonomy

The Frye and Edidin experiment demonstrated that lateral protein movement within the cell is affected by

temperature

A key function of collagen is to impart ___________ strength to certain parts of an animal's body.

tensile

The mode of cell communication depends on: the diffusion rate between the cells the response of the cells to each other the distance between the cells that need to communicate

the distance between the cells that need to communicate

Water has a high heat of vaporization because of the polar nature of the covalent bonds between H-O the presence of Brownian motion in liquid water the high number of hydrogen bonds between molecules

the high number of hydrogen bonds between molecules

Scientific discoveries can result from which of the following? Select all that apply. the scientific method gathering new information untestable hypotheses

the scientific method gathering new information

Which of the following are pumped by the Na+/K+ -ATPase? Select all that apply. three Na+ out of the cell two K+ into the cell two ATP out of the cell three Na+ into the cell two ATP into the cell three K+ into the cell

three Na+ out of the cell two K+ into the cell

An organ is composed of two or more types of Multiple choice question. any living thing. organisms. tissues. species.

tissues.

A term that describes a situation in which the concentration of a solute is higher on one side of a membrane than the other is lipid raft. active transport. passive transport. transmembrane gradient.

transmembrane gradient.

Membrane proteins that span both leaflets of the lipid bilayer are called transmembrane proteins. lipid-anchored proteins. peripheral proteins. glycolipid tags.

transmembrane proteins.

If a drug blocked the activity of an integrin, that cell would not be able to respond to changes in the ECM.

true

How many shells of electrons does carbon have?

two

Specialized cellular compartments that are filled with fluid, sometime solids, are called mitochondria vacuoles lysosomes capsules

vacuoles

Select all the regions that are likely binding sites for peripheral membrane proteins. Hydrophilic regions of integral membrane proteins Hydrophobic regions of integral membrane proteins Polar head groups of phospholipids Fatty acid tails of phospholipids

• Polar head groups of phospholipids • Hydrophilic regions of integral membrane proteins