Chromosomes (1/2) Flashcards
State what all inherited characteristics in organisms are determined by
The genes located on DNA in chromosomes
Describe a chromosome
A structure containing a single DNA molecule and its associated proteins
State whether or not chromosomes carry genes
Yes. Chromosomes carry genes.
State whether or not chromosomes can be differently shaped.
Yes
State whether or not chromosomes can have different sizes
Yes
State whether the appearance of chromosomes changes throughout the life of the cell upon which they are present
Yes
State what types of chromosomes are present within eukaryotic organisms
Linear chromosomes
State where linear chromosomes are located in eukaryotic organisms
Nucleus
State whether the number of chromosomes contained within a species is consistent
Yes
State what each chromosome carries
A different set of genes
State to what cells chromosomes are passed to during mitosis
Daughter cells
State to what cells chromosomes are passed to during meiosis
Germline cells
State what types of chromosomes are present within prokaryotic cells
Single circular chromosomes
State what the small, circular DNA molecules in prokaryotes are termed
Plasmids
State whether or not plasmids can move between cells
Yes
State what DNA is coiled about in eukaryotes
Histones
Describe histones
Small proteins
State what the DNA coiled about histones combined form
Nucleosome
State what occurs when a eukaryotic cell is preparing to divide
Chromosomes become condensed and are visible when the cell is stained under a light microscope
State whether prokaryotic chromosomes are more condensed or less condensed than eukaryotic chromosomes
No. They are less condensed.
Describe centromere
Constriction point which divides the chromosome into two sections
State what the regions on either side of the chromosomal centromere are referred to as
Chromosome arms
State what the p arm of a chromosome represents
Shorter arm
State what the q arm of a chromosome represents
Longer arm
State the 4 types of chromosomes
- Metacentric
- Submetacentric
- Acrocentric
- Telocentric
State what the position of a gene on a chromosome is referred to as
Locus
Describe locus
Position of a gene on a chromosome
State what each DNA molecule contains
Many genes
State what the genes of each DNA molecule are separated by
Spacer DNA
Describe spacer regions of DNA
DNA that does not encode for a protein product
State a term to describe the chromosome that has the same loci and are considered a ‘matching pair’
Homologous chromosome
Describe chromatids
Identical copies of a chromosome
Describe homologous chromosomes
Identical chromosomes which pair up during fertilisation
