DNA and Meiosis

HideShow resource information
What are genes?
A length of DNA that contain the coded information for making polypeptides
1 of 27
Why is the code known as degenerate?
Most amino acids are coded for by more than 1 triplet
2 of 27
Why is the code non-overlapping?
Each base in the sequence is only read once
3 of 27
What is an exon?
Coding sequences
4 of 27
What are introns?
Non-coding sequences
5 of 27
What are homologous chromosomes?
One chromosome of each homologous pair comes from the mother (called a maternal chromosome) and one comes from the father (paternal chromosome)
6 of 27
What are the different forms of a gene called?
Alleles
7 of 27
What does mRNA do?
Transfers the DNA code from the nucleus to the cytoplasm
8 of 27
Define codon
Sequence of 3 bases on mRNA that code for a single amino acid
9 of 27
Define genome
Complete set of genes in a cell
10 of 27
Define proteome
Full range of proteins produced by the genome
11 of 27
What shape is a tRNA molecule and why?
Clover-leaf shape so an amino acid can easily attach
12 of 27
What is an anticodon?
Found on tRNA. Complementary to codons
13 of 27
Briefly describe the process of transcription
DNA helicase causes the 2 strands to separate, nucleotide bases on the template strand pair with complementary nucleotides from the pool present in the nucleus, RNA polymerase joins the nucleotides, does this until reaches stop codon. Pre-mRNA made
14 of 27
What is splicing?
Removing introns from pre-mRNA to from mRNA
15 of 27
Does splicing occur in prokaryotes?
No bc they don't contain introns. mRNA is produced directly from transciption
16 of 27
Describe the process of translation
ribosome to starting codon, tRNA anticodon (amino acid attached) pairs with comp mRNA codon, repeat with next codon, 2 amino acids join by peptide bond, ribosome moves to 3rd codon, 1st tRNA released collect another AA, continue until ribo stop codon
17 of 27
Define mutation
Any change in the quantity or base sequences of DNA in an organism
18 of 27
What is substitution?
A nucleotide is replaced by another with a different base
19 of 27
What is deletion?
When a nucleotide is lost from a sequence
20 of 27
What is polyploidy?
When organisms have 3 or more sets rather than the usual 2
21 of 27
What is non-disjunction?
When individual homologous pairs fail to separate during meiosis
22 of 27
What is the diploid number of chromosomes?
46
23 of 27
What is the haploid number of chromosomes?
23
24 of 27
What happens during meiosis 1?
Homologous chromosomes pair up and chromatids wrap around each other. Crossing over may occur. By end homologous pairs separate on chromosome from each pair goes into a daughter cell
25 of 27
What happens during meiosis 2?
Chromatids move apart. Each chromosome goes into a daughter cell (4 daughter cells produced)
26 of 27
What is independent segregation?
During meiosis 1 each chromosome lines up with its **** partner. When arrange in a line do so randomly. Since line up randomly combo of mat and pat chromosomes that go into daughter cells also random
27 of 27

Other cards in this set

Card 2

Front

Why is the code known as degenerate?

Back

Most amino acids are coded for by more than 1 triplet

Card 3

Front

Why is the code non-overlapping?

Back

Preview of the front of card 3

Card 4

Front

What is an exon?

Back

Preview of the front of card 4

Card 5

Front

What are introns?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all DNA, genetics and evolution resources »