bio 4

How many chromosomes does a haploid human gamete have?

23

If you have chromosome 8 from your father + chromosome 8 from your mother, you have:

homologous chromosomes

How many copies of each chromosome are there in a karyotype?

4

In plants, which of the following adult plants is haploid?

gameteophyte

A main difference between animal and fungal replication cycles is:

fungal cycles can have haploid adults

Each of the following occurs twice in meiosis, EXCEPT:

DNA replication

In meiosis I:

homologous chromosomes separate

When homologous chromosomes stick together, this is called:

synapsis

Which of the following is a name for when homologous chromosomes break and exchange DNA?

crossing over

If an organism has 3 haploid chromosomes, how many possible gametes could be formed by independent assortment alone?

8

in mitosis and meiosis the cell is briefly

2n

in mitosis, the final daughter cells are

2n

Which of the following is NOT a method for increasing genetic diversity of offspring?

mitosis

Measurements of the amount of DNA per nucleus were taken on a large number of growing cells.  The measured DNA amounts were typically either 5 or 10 picograms per nucleus.  In which phase of the cell cycle did the nucleus contain 5 picograms of DNA?

G1 phase

What is happening with the chromosomes in this picture?

synapsis

Another possible name or description for an allele is:

gene,the DNA for a genetic trait on a chromosome, the DNA for a phenotypic trait on a chromosome, several nearby related genes on a chromosome coding for a trait

Why did Mendel use pea plants?

peas have many different phenotypic variations

Mendel's Law of Segregation includes all of the following EXCEPT:

alleles behave independently from other alleles

A purple pea flower has which of the following genotypes?

PP or Pp

Mendel observed that traits like flower color and pea (seed) color did not correlate with each other and behaved separately, and he called this:

the law of independent assortment

If you have a purple flowered pea and you a test cross with a white flowered pea, and the offspring are all purple, what was the genotype of the purple pea?

PP

If an organism has the genotype ppYyrr  - how many recessive traits will it express?

2

Consider 2 different plants with the genotypes GgTt and ggtt.  These plants can produce how many types of gametes each?

four and one, respectively

If you cross two homozygotes and get offspring with intermediate traits, this means the alleles were:

incompletely dominant

If you have type A blood, but your child has type B blood, then:

your spouse has type B or AB blood

Which of the following produces the largest range of variation in a trait?

polygenic inheritance

Geneticists often track thousands of F1 and F2 offspring, but humans only have a few offspring, so instead of Punnett squares, in human genetics we often use:

pedigrees

If you are a "normal" height adult and you have 4 children with a homozygous dwarf, on average how many of your children will be dwarfs?

4

In a plant where Y = yellow flowers = dominant and y = green flowers = recessive, if you cross a yellow plant (of unknown genotype) with a green plant and the F1 generation is always green - which of the following is correct:

this is not possible

A Punnett square analysis says that if you have AO type blood and your spouse has AO type blood, that 50% of your children will have type OO blood, but you have 4 children and that are all have type OO blood.  This is because:

You did not have enough children to see the statistical averages

All of the following people or pairs of people made significant advances in our understanding of DNA, which ones did no actual experiments?

Watson and Crick

Who showed that DNA is the genetic material?

Hershey and Chase

If a piece of double stranded DNA has 20% adenine, what % guanine is it?

30%

Replication of double stranded DNA is:

semi-conservative

DNA and RNA sequences have a 5' end and a 3' end (5 prime and 3 prime) - what do the 5' and 3' refer to?

the number of the carbon in the ribose

E. coli genomes have

one origin of replication

Human genomes have

multiple origins of replication

Replication bubbles have

2 replication forks each

Replication forks have

a leading strand and a lagging strand

Which protein actually adds DNA nucleotides to a growing DNA strand?

polymerase

What is the main replicative polymerase in E. coli?

DNA Pol III

DNA is synthesized (and written) in one direction, which direction?

5' to 3'

Which of the following is involved in BOTH leading and lagging strand synthesis?

RNA primase

If the only 3 proteins involved are nuclease, DNA polymerase I, and ligase - what process is occurring?

nucleotide excision repair

What is the end of a chromosome called?

telomere

The first step in DNA condensation involves:

DNA winding around histone proteins to form nucleosomes

DNA replication involves "leading strand synthesis" and "lagging strand synthesis" - why are 2 different procedures required?

because DNA can only be synthesized 5' to 3' but the two strands run in opposite directions

What is the first thing made during DNA replication?

RNA

Which of the following is NOT part of transcription?

making protein

How many different codons are there?

64

Transcription starts when RNA polymerase binds at a

promoter

RNA polymerases can do something DNA polymerases cannot.  What?

begin polymerizing without a primer

Prokaryotes are missing which of the following?

RNA processing

What cuts introns out of an mRNA?

spliceosome

Attaching an amino acid to an tRNA is called:

charging

Which of the following is false?

mRNA has the anti-codon

Ribosomes have A, P, and E sites.  What does E stand for?

exit

A codon is 5' ACG 3', what is the anti-codon?

5'CGU 3'

What is the energy source for translation?

GTP

What part of a protein directs where it goes within the cell?

the signal peptide

When a DNA mutation results in a different amino acid being put into a protein, what kind of mutation is this?

missence

If an mRNA has an intron, that means:

it was made in a nucleus,it will be spliced,it was made in a eukaryotic cell,it also has a poly A tail,

What is "release factor" ?

protein

A promoter + an operator sequence + one or more genes is:

an operon

a repressible operon's default mode is

on mode

an inducible operon's default mode is

off mode

the lac operon's default mode is

off mode

he trp operon's default mode is

on mode

When the cell has too much tryptophan, what does the excess trp bind to in order to shut down trp synthesis?

the trp repressor

Chromatin can be turned "on" for transcription by:

acetylation

What is a co-repressor?

a small molecule that binds to a repressor protein

The lac repressor and the trp repressor:

are transcription factors,are proteins,can bind to DNA,can block RNA polymerase from transcribing a gene

Which of the following is NOT a possible place where expression of different genes is controlled?

transcription of tRNAs

In control of transcription in eukaryotes versus prokaryotes - for eukaryotes the control regions on the DNA are:

more numerous and often farther away from the genes

Which of the following RNA species regulates gene expression as its primary function?

miRNA

Which of the following is not a mechanism for gene regulation?

how long a gene lasts

Which small protein targets or marks other proteins for destruction?

ubiquitin

Alternative RNA splicing produces different mRNAs from the same gene.  How does it do this?

removes different exons from the the alternate mRNAs

Alternative mRNA splicing cannot occur in prokaryotes because:

they have no introns

If the gene for p53 gets damaged, what happens?

it turns into an oncogene,it stops regulating the cell cycle,it sometimes results in cancer,it stops being an effective transcription regulator or alters its regulation pattern,

Some transcriptional regulators are called master regulators because they turn on or off other transcription factors and control many different genes.  Which of these is a master regulation?

MyoD, p53, Ras,Bicoid