Chapter 2

Question 1

DNA

Answer 1

Master Copy of an organism’s genetic information, which is passed from one generation to the next

Question 2

Prokaryotic Cells

Question 3

Eukaryotic Cells

Answer 3

Cells that contain a nucleus, including plant and animal cells, protists, and fungi.

Question 4

Eukaryotic Cells Structure

Answer 4

Question 5

Plasma (cell) membrane

Answer 5

A double-layered structure, consisting of lipids, proteins, and carbohydrates, that defines the boundaries of a cell; performs important roles in cell shape and regulating transport of molecules in and out of a cell.

Question 6

Nucleus

Answer 6

Membrane-enclosed organelle that contains the DNA of a eukaryotic cell.

Question 7

Mitochondria

Answer 7

functions as the powerhouse of the cell because it produces the energy the cell needs to perform it’s duties. The energy currency of the cell is ATP.

Question 8

Ribosomes

Answer 8

Organelle composed of ribosomal ribonucleic acid (rRNA) and proteins assembled into packages called subunits. Ribosomes bind to mRNA and tRNA molecules and are the site of protein synthesis in prokaryotes and eukaryotes.

Question 9

Golgi

Answer 9

functions as the post office in the cell and packages and modifies the proteins.

Question 11

lysosome

Answer 11

is the trash man of the cell because it digests excess or worn out organelles and proteins.

Question 12

Cell Wall

Answer 12

A membrane of the cell that forms external to the cell membrane whose main role is to give cells rigidity, strength and protection against mechanical stress. It is found in cells of plants, bacteria, archaea, fungi, and algae.

Question 13

Vacuole

Answer 13

A vacuole is a membrane-bound sac that plays roles in intracellular digestion and the release of cellular waste products

Question 14

Chloroplast

Answer 14

structure within a green plant cell in which photosynthesis occurs

Question 15

Nucleus -> Chromosomes-> Genes-> Nucleotides

Answer 15

s

Question 16

Nucleotide

Answer 16

Building block of nucleic acids; consists of a five-carbon (pentose) sugar molecule (ribose or deoxyribose), a phosphate group, and the bases adenine (A), guanine (G), cytosine (C), thymine (T), or uracil (U).

Question 17

Genes

Answer 17

A specific sequence of DNA nucleotides that serves as a unit of inheritance. Genes govern visible and invisible characteristics (traits) of living organisms in large part by directing the synthesis of proteins in a cell.

Question 18

transcription

Answer 18

The synthesis of RNA from DNA, which occurs in the nucleus of eukaryotic cells and the cytoplasm of prokaryotic cells.

Question 19

transcription factors

Answer 19

DNA-binding proteins that bind promoter regions of a gene and stimulate transcription of a gene by RNA polymerase.

Question 20

TATA box

Answer 20

Short nucleotide sequence (TATA) usually located approximately 20 to 30 base pairs “upstream” (in the 5′ direction) of the start site of many eukaryotic genes; part of promoter sequence bound by transcription factors used to stimulate RNA polymerase.

Question 21

transcriptional regulation

Answer 21

Form of gene-expression regulation that involves controlling the process of transcription by controlling the amount of RNA produced by a cell

Question 22

transfer RNA (tRNA)

Answer 22

Small RNA molecules that transport amino acids to a ribosome during protein synthesis. tRNA binds to specific codons in mRNA sequences during translation.

Question 23

translation

Question 24

triploid

Answer 24

Three sets of chromosomes (3n); used to describe organisms with three sets of chromosomes.

Question 25

Nucleotide

Answer 25

* Deoxyribose Sugar * Phosphate * Nitrogen Base

Question 26

Purines

Answer 26

double ring A & G

Question 27

Pyrimidines

Answer 27

Single Ring C & T

Question 28

DNA Replication

Answer 28

When DNA makes an exact copy of itself

Question 29

DNA Replication First Step

Answer 29

the enzymes, helicase and gyrase, unzip the double stranded DNA molucule.

Question 30

DNA Replication Second Step

Answer 30

Proteins hold the two strands apart while RNA polymerase (primase) lays down an RNA primer on each strand of DNA

Question 31

DNA Replication Third Step

Answer 31

DNA polymerase extends the primer by adding complementary nucleotides (both DNA Pol III and Pol I) Dna polymerase can only extend in the 5'-3' direction

Question 32

DNA Replication Fourth Step

Answer 32

Leading strand follows helicase Lagging strand must wait for replication fork to open threfore forms discontinous Okazaki fragments Ligase seal the niks between Okazaki fragments

Question 33

leading strand

Answer 33

During DNA replication, the strand of newly synthesized DNA that is copied by DNA polymerase in a continuous fashion, 5′ to 3′ into the replication fork.

Question 34

lagging strand

Question 35

RNA Structure

Answer 35

mRNA rRNA tRNA

Question 36

mRNA

Answer 36

RNA copy of DNA that carries genetic information from the nucleus to the ribosomes

Question 37

rRNA

Answer 37

makes up the ribosmes

Question 38

tRNA

Answer 38

carries amino acids to ribosomes for protein synthesis

Question 39

Transcription

Answer 39

1. RNA polymerase binds to a promoter region one double stranded DNA and unzips the double helix 2. Free RNA nucleotides pair with the complementary DNA of the template strand 3. RNA is processed: introns are spliced out, 7 methyl guanosine cap added to the front and Poly-A tail added to the end 4. mRNA leaves the nucleus and travels to the ribosomes in the cytoplasm (where proteins are made)

Question 40

Codon

Answer 40

* composed of 3 RNA nucleotides * one codon codes for an amino acids

Question 41

Amino Acids

Answer 41

Building blocks of protein structure; combinations of 20 different amino acids can join together by covalent bonds in varying order and length to make a polypeptide.

Question 42

Protein

Answer 42

does the work in a cell

Question 43

RNA Structure

Answer 43

* Uracil instead of Thymine * Ribose sugar instead of deoxyribose sugar * single stranded * can leave nucleus

Question 44

Exons

Answer 44

Protein-coding sequences in eukaryotic genes and mRNA molecules. Introns are between exons, so they have to be cut out so exons can join each other

Question 45

Translation- making protein from mRNA

Answer 45

1. mRNA attaches to the small subunit of a ribosome 2. tRNA anticodon pairs with mRNA start codon 3. Large ribosomal subunit binds and translation is initiated 4. always begins at a start codon and ends at a stop codon (area in between called the Open Reading Frame ORF) 5. Translation Elongation- (to elongate amino acid chain) Anticodon of tRNA carrying next amino acid binds to codon on mRNA. A peptide bond joins the amino acids and the first tRNA is relead 6. Amino acid chain contnues until a stop codon is read and then the chain is released

Question 46

DNA-\> Replication-\> Transcription -\> RNA -\> Translation -\> Protein

Answer 46

process

Question 47

Nucleosome

Answer 47

A structural unit of a eukaryotic chromosome, consisting of a length of DNA coiled around a core of histones.