Bio Final Ch. 1-5

A cell is in metaphase if:

The chromosomes are aligned on the equatorial plate of the cell

Which of the following relationships between cell structures and their respective functions is NOT correct?

Golgi apparatus: breakdown of macromolecules

Which of the following membrane activities does not require the expenditure of energy by the cell?

osmosis

The cohesiveness of water is due largely to:

hydrogen bonds

If the concentration of solutes in a cell s less than the concentration fo solutes in the surrounding fluid, then the extracellular fluid is said to be

hypertonic

Water diffuses through certain organs such as the kedneys and bladder much faster than would occur by passive diffusion through a lipid bilayer alone. What accounts for this more rapid rate of water transport in these organs?

Presence of aquaporin channels for facilitated diffusion of water

There are 20 different amino acids that make up proteins in living organisms. What is the primary difference between these amino acids?

R groups

Which of the following does not occur during meiosis I?

Separation of sister chromatids

Which of the following statements is incorrect concerning sister chromatids?

Sister chromatids are held together at the centromere by kinetochore proteins

_____ contain identical DNA sequences and are held together by______

Sister chromatids; centromeres

What are the possible phenotypes of the children if the mother's genotype if IAio) for blood type and the father is IAIB?

1/2A: 1/4B:1/4AB

A pH of 4 is ______________ times more ________________than a pH of 7

1000; acidic

An animal with a diploid number of 36 chromosomes will ahve _____chromosomes in its gametes and _____ chromosomes in its somatic cell

18;36

An atom with 13 protons and 14 neutrons has an atomic mass of:

27

The molecular weight of NaCl is 58.44. How many grams of NaCl would you need to dissolve in water to a final volume of one liter to make a 0.5 molar solution?

29.22

Analysis of a DNA molecule revealed that it contained 20% thymine bse. What percentage of cytosine base does it contain?

30%

In a two point test cross, 36 of the offspring were recombinant types. The remaining 64 offspring were parental types. How many map units separate the two loci?

36

How many molecules are present in one mole of C6H12O6?

6.02 x10^23 molecules

*Considering the twenty amino acids, how many possible tripeptides are there?

8000

Which of the following relationships holds true about chromosomal content during different phases of the cell cycle?

A cell in G2 has more DNA than a cell in G1 and a cell in the middle of the S phase

What is the main difference between a fat (triglyceride) and a phospholipid?

A phospholipid has 2 fatty acids attached to glycerol, whereas a fat has 3.

How might a plant cell compensate for the excessive membrane fluidity that occurs during prolonged exposures to elevated temperature?

Alter the lipid composition to have longer fatty acyl tails and fewer double bonds.

The kinetochore serves which of the following functions?

Attach to microtubules during mitosis

All of the following statements about cellulose are true EXCEPT:

Certain animals like ourselves can easily digest cellulose and use it as a source of energy.

Breeding a yellow dog with a brown dog produced puppies with both yellow and brown hairs. this is an example of:

Codominance

The offspring of two heterozygous gray-bodied, normal-winged flies should be 50% gray-bodied/normal wings (BbRr) and 50% black-bodied/vestigal wings (bbrr) because these alleles are tihgtly linked. If a small nuymber, say 15%, of the offspring are instead black-bodied with normal wings, this is most likely the result of:

Crossing-over

Nucleotides are the building blocks for:

DNA and RNA

DNA vs RNA

DNA: Double strand, deoxyribose, thymine base RNA: Single strand, ribose, uracil base

Mendel established true-breeding pea plants for certain traits before undertaking his experiments. The term "tru-breeding" refers to:

Genetically pure lines

A cell in G2:

Has twice the amount of DNA present in a telophase nucleus

Place the following events of mitosis in the correct order. IV. Sister chromatids condense III. the nuclear membrane breaks up I. Sister chromatids align on the metaphase plate. V. sister chromatids separate. II. The cleavage furrow forms

IV, III, I, V, II

What is meant by the term "fluid mosaic model"?

It is the movement of lipids and integral membrane proteins within the lipid bilayer

Which of the following pairs is mismatched?

Lysosome-protein synthesis

The term "dominant" means

One allele can mask the expression of another in a hybrid

The probability that two genes will be separated by crossing over is related to:

The distance between the two genes on the chromosome

Which of the following statements concerning unsaturated fats is correct?

They are generally liquid at room temperature

During an infection, white blood cells travel to the infected site and phagocytize the pathogens. After phagocytosis, primary lysosomes fuse with the phagocytic vesicle to form a larger vesicle called a secondary lysosome. The reason for this is:

To mix the pathogens with strong hydrolytic enzymes and destroy them

Mating an individual expressing a dominant phenotype, but whose genotype is unknown, with an individual expressing the corresponding recessive phenotype is an example of:

a test cross

Cytokinesis in animal cells involves contraction of a ring of _______microfilaments.

actin

When a small amount of hydrochloric acid (HCL) is added to a solution of Na2HPO4, the pH of the solution does not change markedly. The pH also does not change drastically when a small amount of sodium hydroxide (NaOH) is added to this same solution. Based on these observations, the compound Na2HPO4 is:

acting as a buffer

A bacterium containing sodium ions at a concentration of 0.1mM lives in a pond that contains sodium ions at 0.005 mM. Evidently, sodium ions are entering the cell by.

active transport

________ are alternative versions of genes that govern the same characteristic, such as eye color, and occupy corresponding positions on homologous chromosomes.

alleles

The difference between an electrically neutral atom and an ion is that:

an ion has an unequal number of protons and electrons, while an atom has an equal number

Receptor-mediated endocytosis:

brings about the selective uptake of materials by enclosing them in membranous vesicles

The five carbon sugar unit of DNA is

deoxyribose

One function of peroxisomes involves the process of:

detoxification

The force necessary to cause microtubules of cilia and flagella to slide alongside one another is provided through the action of _______proteins.

dynein

The release of insulin from pancreatic cells occurs by

exocytosis

All of the following are inorganic molecules except:

glucose

Which of these is NOT a lipid?

glycogen

The combination of two monosaccarides forms a __________linkage.

glycosidic

Proteins made on ribosomes may be further modified within the:

golgi complex

One strategy that allows larger cells to have an effective surface area to volume is:

having thin, finger-like projections

In a lipid bilayer, ____________fatty acid tails face each other within the bilayer and form a region that excludes water.

hydrophobic

The situation in which some members of a population with a given genotype do not express the expected phenotype is referred to as

incomplete penetrance

In a dihybrid cross, the ratio 9:3:3:1 indicates

independent assortment

Peripheral membrane proteins are linked to either surface of the plasma membrane by:

interactions with integral membrane proteins or polar head groups of phospholipids

Which cytoskeletal structures represent a highly diverse group of tension-bearing fibers important to the maintenance of cell shape?

intermediate filaments

In water, MgCl2 dissociates into Mg2+ and CL-. Based on this information what type of bond is involved in the formation of MgCl2?

ionic

Two molecules with identical molecular formulas but that have different structures are called

isomers

Which of the following statements about the sodium-potassium pump is true?

it transports 3 sodium ions out of the cell in exchange for 2 potassium ions

Which statement is most true about the endoplasmic reticulum

it typically represents a significant portion of the total membrane of the cell

A covalent bond:

may be polar or nonpolar depending on the atoms involved

Which of the following pairs is correctly matched?

nucleolus--site of ribosomal subunit synthesis

Phospholipids contain a hydrophilic ___________attached to glycerol.

phosphate

3 components of a nucleotide

phosphate group, base, sugar

Nucleotides are connected together by ________ linkages

phosphodiester

Amylose is:

plant starch

Gap junctions are to animal cells as___________ are to plant cells?

plasmodesmata

Mitochondria

play a central role in energy metabolism

A particular gene that controls seed coat color in peas also determines the susceptibility of these peas to a particular disease. This situation is referred to as

pleiotropy

Ribosomes are responsible for

protein synthesis

Facilitated diffusion:

requires a transmembrane protein

In the first step for ribosomes to dock on the ER, this molecule or complex recognizes the ER signal sequence within proteins during the translation process.

signal recognition particle

These are short amino acid sequences that direct proteins to their correct location within the cell.

sorting signals

All of the following functions are performed by plant vacuoles except:

storage of nucleic acids

Disulfide bridges formed between cysteine amino acid residues are part of a protein's ____________structure.

tertiary structure

Which of the following statements about plasma membranes in INCORRECT?

they are relatively rigid structures

This forms a seal that prevents the movement of substances between cells, for instance from the intestinal lumen into the blood

tight junctions

A ________ is used to demonstrate the linkage of two genes.

two-point test cross

The binding (or fusion) of vesicles to target membranes require which of the following?

v-snare and t-snare interactions

When pink-flowered plants were crossed they produced offspring with red, pink, and white flowers in a ratio of 1:2:1. This is an example of:

Incomplete dominance

Which of the following statements about the ECM is most CORRECT?

Its components are produced and secreted by the cell

Chromosomes become duplicated during the

S phase

Which of the following is NOT a property of fat or of fatty acids?

They are soluble in water

The physical location of a particular gene on a chromosome is called:

a locus

DNA double strands are held together by:

hydrogen bonds

Carbon and hydrogen have similar electronegativites and combine together to form hydrocarbon molecules. What type of bonds form between these atoms?

nonpolar covalent

Which of the following events occurs during prophase?

nuclear envelope breaks down, nucleoli disappear, spindle fibers attach to the kinetochores, chromosomes condense

Which molecules are essential components of tight junctions?

occludin and claudin

Biological membranes are normally permeable to:

small, hydrophobic molecules

Lipids are attracted to one another by:

van der Waals interactions

Homologous chromosomes come together or pair during

Prophase 1

It is advantageous for cells to be small because:

a small cell has a small cell volume relative to surface area, thereby increasing efficient transport

If a testcross for two different traits produces more nonrecombinant than recombinant offspring, then the alleles for the two traits

are on the same chromosome

G1 and M specific cyclins bind to these molecules to form active complexes that promote progression through different phases of the dcell cycle. what molecules do cyclins bind to?

cyclin-dependent kinases

This cytoskeletal structure is composed of actin and regulates cell shape, cell movement, and muscle contraction.

microfilaments

The _______________ is responsible for the separation of the chromosomes during ___________ of mitosis.

mitotic spindle; anaphase

DNA associates very tightly with nucleosomes because

negative charges on DNA are attracted to positive charges of the histone proteins.

Isotopes differ from each other with respect to the number of:

neutrons

Electron microscopes have a much higher resolution than either the human eye or any light microscope because:

of the very short (nanometer) wavelengths of electrons

Chlorine has seven electrons in its outer shell. The number of additional electrons it would like to have to complete this shell is:

one

_________refers to multiple independent pairs of genes having similar and additive effects on the same characteristic

polygenic inheritance

Amphipathic molecules

possess both hydrophilic and hydrophobic properties

Which of the following is not a constituent of the nucleus?

protein modifying enzymes

At the end of meiosis I

the cells are haploid and the homologous pairs are in separate cells

A saturated fatty aid contains

the maximum number of hydrogen atoms in the fatty acid chains

The process of making macromolecules from smaller monomers by removing an -OH from one monomer and a -H from another monomer to link them together is called a ________ reaction.

condensation

Microtubules that radiate from _______________help divide chromosomes during cell division.

centrioles

A cellular structure found in plant but not animal cells is the

chloroplast

Which of the following is a typical component of eukaryotic cell membranes?

cholesterol