Bio 111 Midterm #2 UPDATED ACTUAL Questions and CORRECT Answers

Bio 111 Midterm #2 UPDATED ACTUAL
Questions and CORRECT Answers
Deoxyribonucleic Acid - CORRECT ANSWER - (DNA)
-Nucleic acid that stores info
-Made up of nucleotides->molecule of sugar, phosphate group, and a base
-Backbone made up of sugar alternating w/ mol of phosphate
-Bases are attached to each sugar


Base Pair - CORRECT ANSWER - -Part of DNA
-Adenine and Thymine
-Cytosine and Guanine


Genetic Code - CORRECT ANSWER - Holds the detailed instructions for the amino acid
sequences of polypeptides that fold up to make proteins to build every organism


Genome - CORRECT ANSWER - -Full set of DNA in the nucleus in eukaryotes
-Circular pieces of DNA in prokaryotes


Chromosome - CORRECT ANSWER - -Smaller, manageable pieces of DNA
-We have 46 (23 from mom, 23 from dad)
-Number varies from species to species but is not related to how complex an organism is


Gene - CORRECT ANSWER - -Sequence of base pairs in a DNA molecule that carries
info necessary for producing a functional product (usually a polypeptide or RNA mol)
-Also contains instruction set for producing one specific molecule, usually a protein


Alleles - CORRECT ANSWER - -Alternative versions of a gene that code for the same
trait

,-ex. eye color, shape of nose


Junk DNA - CORRECT ANSWER - -Huge portion of base sequences in DNA that do not
code for anything and have no known purpose
-Bacteria and viruses tend to have very little and eukaryotes have a lot
-Sometimes it encodes small parts of RNA mols that function in gene regulation


Keep going! - CORRECT ANSWER - You're doing great



Genotype - CORRECT ANSWER - Genes that an organism carries for a particular trait



Phenotype - CORRECT ANSWER - The physical manifestation of a trait



Transcription - CORRECT ANSWER - -When a copy of a gene's base sequence is made
-Occurs in nucleus (euk) or cytoplasm (prok)
-Gene's base sequence is copied into a middleman called mRNA
-mRNA then moves out of nucleus into cytoplasm, where translation happens


Translation - CORRECT ANSWER - The copy made in transcription is used to direct the
production of a polypeptide which then, due to a variety of factors including the cellular envi,
folds into a protein


Steps of Transcription - CORRECT ANSWER - 1. Recognize and Bind: RNA polymerase
recognizes a promoter site, binds to it, and unwinds just a bit so only one strand of DNA can be
read
2. Transcribe: RNA poly builds a copy of the gene called mRNA which can move elsewhere in
the cell and used to make a protein
3. Terminate: When mRNA reaches the termination sequence, it stops creating the transcript and
detaches from DNA

, 4. Capping and Editing: (euk) mRNA receive a cap and tail to protect them and promote
recognition, and introns are removed


Termination Sequence - CORRECT ANSWER - Sequence at the end of a gene that tells
mRNA to stop and detach in the third step of Translation


Introns - CORRECT ANSWER - -Non-coding sections of DNA
-Binding sites for regulatory processes


Exons - CORRECT ANSWER - Code for amino acids to make proteins



Things you need for Translation to Occur - CORRECT ANSWER - 1. Large #s of free
amino acids floating around
2. Ribosomal subunits
3. Molecules that can be read in mRNA code and translate that message into a protein


Ribosomal Subunits - CORRECT ANSWER - Protein-production factories where amino
acids are linked together in the proper code in order to produce a protein


Transfer RNA - CORRECT ANSWER - (tRNA)
Interpret mRNA code, translating it by linking specific bases on the mRNA with specific amino
acids to make a protein


Codon - CORRECT ANSWER - -3 base sequence in mRNA that matches to tRNA mol
that carries a particular aa
-64 possible (however, UGU and UGC, for example, are the same)


Steps of Translation - CORRECT ANSWER - 1. Recognize and initiate protein building
(cytoplasm): Subunits of a ribosome recognize and assemble around mRNA (based on AUGC)
and the tRNA and mRNA mols bind as ribosomal subunits assemble around them