Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
11 Cards in this Set
- Front
- Back
Prokaryotes |
- have one chromosomes consisting of cicular DNA molecule - some prokaryotes also have plasmids but eukaryotes do not |
|
Eukaryotes |
- eukaryote chromosomes are linear DNA molecules associated with histone proteins - there are different chromosomes that carry different genes - chromosomes replicate in interphase before meiosis |
|
Homologous Chromosomes |
- carry the same sequence of genes but not necessarily the same alleles of those genes - separate in meiosis 1 - the early stages of meiosis involve pairing of homologous chromosomes and crossing over followed by condensation - orientation of pairs of homologous chromosomes prior to seperation is random - separation of pairs of homologous chromosomes in the first division of meiosis halves the chromosomes number |
|
Diploid Nuclei |
- have pairs of homologous chromosomes |
|
Haploid Nuclei |
- have one chromosomes of each pair |
|
Karyogram |
- shows the chromosomes of an organism in homologous pairs in decreasing lengths - listed by length and structure |
|
Sex Chromosomes |
- sex is determined by sex chromosomes - automates are chromosomes that do not determine sex |
|
Karyotype vs. Karyogram |
Karyotype - property of the cell, the number and type of chromosomes present in the nucleus Karyogram - the diagram |
|
Genome Size |
- total length of DNA in an organism |
|
Sister Chromatids |
- two DNA molecules formed by DNA replication prior to cell division are considered to be sister chromatids until the splitting of the centromere at the start of anaphase. - after this, they are individual chromosomes - separate in meiosis 2 - chiasmata formation between non-sister chromatids can result in an exchange of alleles |
|
Independent Assortment |
- independant assortment of genes is due to random orientation of pairs of homologous chromosomes in meiosis 1. - crossing over and random orientation promotes genetic variation -fusion of gametes from different parents promotes genetic variation |