What is mitosis?
Production of somatic cells
Growth, differentiation, repair
Does mitosis include cell division?
No- that is cytokinesis
What is meiosis
Production of gametes
What is the period between mitoses known as?
Interphase
What phase are most cellular activities performed?
Interphase
What are the three phases of interphase?
G1
S
G2
What is M phase?
Mitosis and cytokinesis
What happens during G1 phase?
First gap phase
Rapid growth and development
Where cell does its job
What happens during S phase?
DNA is replicated
What happens during G2?
Final growth and prep for M phase
What are the 3 checkpoints of the cell cycle?
G1 checkpoint
G2 checkpoint
M checkpoint
What is chromosome segregation?
Distributing a copy of each chromosome to each daughter cell
List the order of the phases of mitosis?
Prophase Prometaphase Metaphase Anaphase Telophase Cytokinesis
In which phase do centromeres split and chromosomes migrate?
Anaphase
IN which phase do chromosomes undergo congression?
Metaphase
IN which phase does the nuclear membrane fall apart?
Prometaphase
In which phase is there chromosome condensation, formation of centrosomes?
Prophase
In which phase do nuclei reform?
Telophase
In a chromosome, which is short arm?
p
In a chromosome, which is the long arm?
q
What happens during meiosis I?
Reduction division and genetic recombination
What is meiosis II similar to?
Mitosis
In prophase I, what are points of crossing over known as?
Chiasmata
What is a tetrad?
Group of four chromatids
How many genes does the human genome have?
about 25,000
What is the central dogma of biology?
DNA –> RNA –> protein
How is RNA different from DNA?
Has ribose (not deoxyribose) Uracil (instead of thymine) Single stranded (instead of double)
What is the process of DNA –> mRNA known as
transcription
What is the process of mRNA –> protein known as
Translation
What is a sequence of DNA that is required for the production of a functional product?
Gene
What is a promoter?
At 5’ end, required for initiation of transcription
Help to regulate tissue specificity
What does the 3’ end of a gene signal for?
Addition of polyA tail
What do gene families share?
Related DNA sequences and closely related polypeptides
What is a gene family clustered on chromosome 11?
Beta globin
Where is the OR gene family located?
Throughout the genome
What are non-coding segments due to mutations that are found in gene families?
Pseudogenes
What is a non-processed pseudogene?
Dead genes
What is a processed pseudogene?
Has no introns
Where does transcription begin?
5’ UTR (untranslated region)
What happens before mRNA is transported to cytoplasm?
5’ and 3’ modifications occur
Introns removed
Exons spliced
What does translation use?
Ribosome and tRNA
What way does DNA read?
3’ –> 5’
Which way is RNA produced?
5’ –> 3’
What is another name for the untranscribed DNA strand?
Coding strand
What is the transcribed also known as?
Non-coding (anti-sense)
Where is the site of protein synthesis?
Ribosomes (composed or rRNA and protein)
What is the start codon?
AUG
How many stop codons are there?
3
UGA, UAA, UAG
The genetic code is _________
Degenerate
How many introns and exons does the Beta globin gene have?
3 exons
2 introns
The Beta globin gene is only expressed in what type cells?
Erythroid
Where is the TATA box located?
25-30 bp upstream
Where is the CAT box located?
upstream from TATA
What do mutation in TATA or CAT lead to?
alters levels of transcription
What do housekeeping genes contain?
CpG islands
What are enhancers?
Activating sequences several kb from gene
What happens in RNA splicing?
Introns are removed
What is found at the 5’ end of an intron?
GT
What is found at a 3’ end of an intron?
AG
What is alternative splicing?
Multiple splicing patterns
Can create multiple, related mRNAs from a single gene
What is polyadenylation?
Mature mRNA contains 130 bp of 3’ UTS between stop and polyA tail
What sequence controls the cleavage of 3’ end and addition of polyA tail
AAUAAA 20 bp upstream of poly A site