Mick Jagger slides

Question 1

Define diploid and haploid

Answer 1

Diploid = two copies
Haploid = one copy

Question 2

1) Define aneuploid. When is this term usually used?
2) Define polyploid

Answer 2

1) Wrong number of copies; in relation to one chromosome in an individual
2) Too many copies of everything

Question 3

1) Define chromatin
2) What are histones?

Answer 3

1) Complex of DNA and histones that makes up a chromosome
2) DNA binding proteins that chromatin wraps around

Question 4

1) What is “loosely wrapped” around histones? What is its unique characteristic?
2) What is “tightly wrapped” around histones? What is it inaccessible for?

Answer 4

1) Euchromatin; open in some places
2) Heterochromatin; inaccessible for transcription

Question 5

DNA structure:
1) RNA polymerase binds at the _________________ and initiates transcription
2) Define exon

Answer 5

1) promoter region
2) DNA sequences that are transcribed into mRNA and translated into an amino acid sequence of a protein

Question 6

DNA structure:
1) Define intron
2) Define terminator region

Answer 6

1) DNA sequences that are transcribed, but are spliced out of the pre-mRNA (&not included in the mRNA)
2) DNA sequence that signals the end of transcription

Question 7

DNA/mRNA structure:
1) Define cap. What is it attached to and when?
2) Define splicing

Answer 7

1) A modified base (guanine nucleotide) attached to the 5’ end of eukaryotic mRNA molecules during RNA processing
2) Introns are spliced out to produce mature mRNA

Question 8

DNA/ mRNA structure:
1) Define Poly-A tail
2) What is it added to and when?

Answer 8

1) A string of 30-100 adenine (A) nucleotides
2) 3’end of mRNA molecules during RNA processing

Question 9

After polypeptides leave the ribosome, they are __________-ed, _____________-ed, and _______________-ed

Answer 9

folded, modified, and transported

Question 10

1) Polypeptides fold into a ___________-dimensional shape, often assisted by other proteins, called _______________.
2) True or false: polypeptides can be chemically modified in many different ways, producing functionally different proteins from one polypeptide
3) When can a polypeptide be called a protein?

Answer 10

1) three; chaperones
2) True
3) After it has been folded, modified, and becomes functional

Question 11

True or false: About half of the material in our DNA only happens once.
Explain your answer

Answer 11

True; “Single-Copy DNA sequence”
-Genes are here

Question 12

1) The half of the material in our DNA that happens more than once has distinct classes of what?
2) What are these called?

Answer 12

1) “repetitive DNA sequences”
2) Alu family and LINE segments

Question 13

1) Define Epi (in epigenetics)
2) Why is it called this?
3) What do epigenetics have an effect on?

Answer 13

1) On top or above
2) “above” the code – DOES NOT CHANGE DNA CODE
3) Which genes are transcribed and when

Question 14

What are the 3 main routes of epigenetics?

Answer 14

1) DNA methylation
2) Histone modifications
3) Histone variants

Question 15

List the 4 types of protein structures

Answer 15

1) Primary (strand)
2) Secondary (alpha helix)
3) Tertiary (bundle)
4) Quaternary (a bunch of bundles)

Question 16

Where are most of the genes located?

Answer 16

The single-copy DNA sequence half of the genome

Question 17

In spermatogenesis:
1) One spermatogonium (2n) in the testis divides by mitosis to produce what two things?
2) What does one of those then divide into?

Answer 17

1) One spermatogonium and one primary spermatocyte
2) One primary spermatocyte (2n) divides by meiosis I to form to two secondary spermatocytes (n)

Question 18

Spermatogenesis:
1) Two _____________________ (n) divide by meiosis II to form four _________________(n).
2) These four things undergo structural changes to become what?
3) What are the end products of spermatogenesis (meiosis I and II)?

Answer 18

1) secondary spermatocytes; spermatids
2) Functional spermatozoa (sperm)
3) Four functional gametes: spermatozoa

Question 19

1) What is the first cell of oogenesis and what does it divide into?
2) When is development arrested?

Answer 19

1) One oogonium (2n) in the ovary divides by mitosis to produce one oogonium and one primary oocyte
2) The primary oocyte undergoes prophase I and then waits until puberty

Question 20

Oogenesis:
1) When menses begins, what finishes dividing? What does it form?
2) What is the last step of oogenesis? What are the end products?

Answer 20

1) One primary oocyte (2n) in the ovary finishes dividing by meiosis I to form one secondary oocyte (n) and one polar body
2) One secondary oocyte (n) divides by meiosis II to form one ovum (n) and one more polar body

Question 21

In oogenesis, the division of the cytoplasm in meiosis I and II is unequal, so in the end we have how many gametes and polar bodies?

Answer 21

One functional gamete (ovum or egg) & 2 Polar bodies

Question 22

Oogenesis:
1) The primary oocyte undergoes ______________ and then waits until puberty
2) Where are homologues condensed and separated?

Answer 22

1) prophase I
2) Prophase I

Question 23

1) Human cells have how many mitochondria? What does each contain?
2) Are mitochondrial genes are inherited exclusively maternally, paternally, or from both?

Answer 23

1) Hundreds to thousands of mitochondria; many copies of the mitochondrial chromosome
2) Exclusively maternally

Question 24

1) Define allele
2) What can it describe the variance of? What does this suggest?

Answer 24

1) One of the alternative versions of a gene or DNA sequence at a given locus
2) The variance that exists in a single gene; points to the extant variation in an individual

Question 25

Define polymorphism

Answer 25

An occurrence of mutation at least as common as 1%

Question 26

1) What causes chromosome disorders/ defects?
2) True or false: chromosome disorders are uncommon
3) Chromosome disorders occur in about ________ out of every 1000 liveborn infants
4) Chromosome disorders are responsible for about _______ of all spontaneous 1st trimester abortions

Answer 26

1) An excess or a deficiency of the genes contained in whole chromosomes or chromosome segments
2) False; they’re common
3) 7
4) 1/2

Question 27

1) What causes single-gene disorders?
2) Where may this be located? (3 places)

Answer 27

1) Mutations in individual genes
2) Mutant gene may be on an autosome, a sex chromosome, or in the mitochondrial genome

Question 28

1) Are single-gene disorders common? What is the frequency out of 1000?
2) Do they account for a significant proportion of disease and death? Explain.

Answer 28

1) They are rare: ~1 in 1000 is the highest but the freq. is usually much lower
2) Yes, although individually rare, they account for a significant proportion of disease and death

Question 29

1) Single-gene disorders affect what percent of the population sometime during their life?
2) Incidence of serious [single-gene] disorders in the pediatric population is about ________%; among hospitalized children about _____-_____%

Answer 29

1) 2%
2) 0.36%; 6-8%

Question 30

1) What is responsible for the majority of diseases?
2) What kinds of disorders does this include?

Answer 30

1) Multifactorial inheritance
2) Prenatal developmental disorders, as well as many common disorders in adult life

Question 31

1) How does multifactorial inheritance cause disease?
2) Incidence of multifactorial diseases is about ____% in the pediatric population and about ____% in the entire population

Answer 31

1) Multiple different genes act together, often in concert with environmental factors
2) 5%; 60%