Big Idea 3

Question 1

Alternative Splicing

Answer 1

a regulated process during gene expression that results in a single gene coding for multiple proteins; particular exons of a gene may be included within or excluded from the final, processed messenger RNA (mRNA) produced from that gene

Question 2

Aneuploidy

Answer 2

the presence of an abnormal number of chromosomes in a cell (too many or too little)

Question 3

Cell plate

Answer 3

only in plants; develops at midpoint between the two groups of chromosomes in a dividing cell and that is involved in forming the wall between the two new daughter cells

Question 4

Centromere

Answer 4

the part of a chromosome that links sister chromatids; during mitosis, spindle fibers attach to the centromere via the kinetochore

Question 5

Cleavage Furrow

Answer 5

the indentation of the cell’s surface that begins the progression of cleavage, by which animal (some algae) cells undergo cytokinesis; actin and myosin (proteins) form cleavage furrow

Question 6

Codominance

Answer 6

recessive and dominant traits appear together in the phenotype; creates a new phenotype; ex- red + white = red and white spotted

Question 7

Incomplete Dominance

Answer 7

dominant and recessive traits blend to form new phenotype; ex- red + white = pink

Question 8

Conjunction

Answer 8

???

Question 9

Crossing Over

Answer 9

the exchange of genes between homologous chromosomes, resulting in a mixture of parental characteristics in offspring

Question 10

Ctokinesis

Answer 10

the cytoplasmic division of a cell at the end of mitosis or meiosis, separating the two daughter cells

Question 11

DNA

Answer 11

a self replicating material present in nearly all living organisms; carrier of genetic information

Question 12

DNA ligase

Answer 12

a specific type of enzyme that facilitates the joining of DNA strands together by catalyzing the formation of a phosphodiester bond

Question 13

Phosphodiester bond

Answer 13

the linkage between the 3’ carbon atom of one sugar molecule and the 5’ carbon atom of another (deoxyribose in DNA and ribose in RNA); strong covalent bonds form between the phosphate group and two 5-carbon ring carbohydrates over two ester bonds

Question 14

DNA Methylation

Answer 14

the addition of a methyl (CH3) group to the cytosine or guanine nucleotides; methyl group added to fifth carbon of cytosine base or sixth nitrogen of adenine base

Question 15

DNA polymerase

Answer 15

a type of enzyme that is responsible for forming new copies of DNA

Question 16

DNA replication

Answer 16

the process by which a double-stranded DNA molecule is copied to produce two identical DNA molecules ; daughter cells of DNA are identical

Question 17

Epistasis

Answer 17

effect of one gene is dependent on the presence of one or more ‘modifier genes’; one combination of such genes has a dominant effect over other combinations

Question 18

Euchromatin

Answer 18

a lightly packed form of chromatin (DNA, RNA, and protein) that is rich in gene concentration and is often under active transcription; most of the active portion of genome

Question 19

Helicases

Answer 19

enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes; RNA and DNA helicases; DNA helicases separate double-stranded DNA into single strands during DNA replication

Question 20

Hemizygous

Answer 20

characterized by one or more genes that have no allelic counterparts (X paired with Y or genetic deficiency)

Question 21

Heterochromatin

Answer 21

a tightly packed form of DNA; many functions including gene regulation; constitutive (affect genes near them.. repetitive, forms centromeres and telomeres) or facultative (genes are silenced through mechanism, not repetitive)

Question 22

Independent Assortment

Answer 22

formation of random combinations of chromosomes in meiosis and of genes on different pairs of homologous chromosomes by passage of one of each diploid pair of homologous chromosomes into each gamete independently of eachother

Question 23

Inducible Operon

Answer 23

a regulatory repressor protein is normally bound to the operator, which prevents the transcription of the genes on the operon; if inducer is present, it binds to repressor and changes its conformation so that it is unable to bind to the operator

Question 24

Kinetochore

Answer 24

protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart

Question 25

Lysogenic Cycle

Answer 25

Viral reproduction; bacteriophage nucleic acids enters hosts' bacterium genome, but bacterium lives and reproduces normally

Question 26

Lytic Cycle

Answer 26

Viral reproduction; destruction of infected cell; viral DNA exists as separate molecule within bacterial cell, replicates separately from host

Question 27

Meiosis

Answer 27

a specialized type of cell division which reduces the chromosome number by half; one cell makes four with 1/2 DNA

Question 28

Nondisjunction

Answer 28

failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually results in abnormal distribution of chromosomes in daughter nuclei

Question 29

Nucleotide

Answer 29

organic molecules that serve as monomers of nucleic acids like DNA and RNA; building block of nucleic acids; composed of a nitrogenous base, 5-carbon sugar, and at least one phosphate group

Question 30

Operons

Answer 30

units made up of linked genes which regulate other genes responsible for protein synthesis

Question 31

Pilus

Answer 31

a hairlike appendage found on the surface of many bacteria; adheres bacterial cell to other cell

Question 32

Polygenic Inheritance

Answer 32

occurs when one characteristic is controlled by two or more genes; genes are large in quantity but small in effect; ex- height, skin color, eye color, weight

Question 33

Purine

Answer 33

a colorless crystalline compound substituted derivatives found in DNA and RNA (adenine and guanine)

Question 34

Pyrimidine

Answer 34

colorless crystalline compound substituted in DNA (thymine and cytosine)

Question 35

Repressible Operon

Answer 35

activated repressor protein binds to operator and prevents transcription

Question 36

Splicing

Answer 36

modification of mRNA

Question 37

Synapsis

Answer 37

fusion of chromosome pairs at the start of meiosis

Question 38

Telomere

Answer 38

a region of repetitive nucleotide sequences at each end of chromatid; protects the ends from deterioration or fusion with other chromosomes

Question 39

Transduction

Answer 39

the process by which DNA is transferred from one bacterium to another by a virus; does not require physical contact

Question 40

Transformation

Answer 40

the genetic alteration of a cell resulting from the direct uptake of exogenous DNA from its surroundings; only occurs when bacteria is in state of competence (ability to uptake naked DNA)

Question 41

Allele

Answer 41

One of two alternative forms of a gene that arise by mutation and are found at the same place on a chromosome