Bio exam 5 slides 3

Question 1

Epigenetic regulation

Answer 1

-1st level
-Control of access to DNA
-Occurs before transcription

Question 2

Alternative splicing

Answer 2

-Different combination of exons in mRNA are spliced together

Question 3

Micro mRNAs

Answer 3

-Degrades mRNAs

Question 4

Inhibited translation

Answer 4

-By miRNAs
-modification of mRNAs 5 cap
-Translational repressor

Question 5

Euchromatin

Answer 5

-Diffuse and light staining
-Unmethylated
-Contains genes that are not transcribed

Question 6

Heterochromatin

Answer 6

-Condensed, dark staining
-Methylated
-Contains genes that are not transcribed

Question 7

Epigenetic control: specific

Answer 7

-DNA is tightly wound on 8 histones to form nucleosome complexes
-Genes must be unwound to be transcribed
-Transcription factors cannot bind to promoter

Question 8

Methylization (tight) of cytosine (CpG) islands

Answer 8

-decrease transcription

Question 9

Methylization (tight) of histone proteins

Answer 9

-Decrease or increase transcription based on location

Question 10

Acetylization (loose) of histone proteins

Answer 10

-Increase transcription

Question 11

Environmental factors

Answer 11

-Chemicals, smoke, stress plays a role in epigenetic modifications and gene regulation

Question 12

Calico cat

Answer 12

-Has X chromosome inactivation
-Black is Xx (big B)
-Orange is Xx (big O)
-2 sets of X chromosomes

Question 13

Promoter

Answer 13

Basal transcription and RNA polymerase bind

Question 14

Enhancer

Answer 14

-DNA sequence that can be far from gene
-Contains distal control elements, transcriptional activators bind

Question 15

Binding to untranslated regions

Answer 15

-Influences RNA stability
-mRNA localization
-Protein translation