Biology 8-1
diploid
Cells having two sets of chromosomes are diploid.
centromere
The two chromatids of a chromosome are attached at a point called a centromere.
homologous chromosome
The two copies of each autosome are called homologous chromosomes, or homologues. Homologous chromosomes are the same size and shape and carry genes for the same traits.
How do the structure and location of a prokaryotic chromosome differ from that of a eukaryotic chromosome?
A prokaryotic chromosome consists of a circular DNA molecule. Eukaryotic chromosomes are rod-shaped, associated with histone and non histone proteins, and found within the cell's nucleus.
autosomes
All of the other chromosomes in an organism are called autosomes.
chromosome
Chromosomes are rod-shaped structures made of DNA and proteins.
Name the proteins that DNA wraps around to form a chromosome in eukaryotic cells.
Histones
karyotype
Karyotype is a photomicrograph of the chromosomes in a normal dividing cell found in a human.
Does chromosome number indicate whether an organism is a plant or an animal? Explain.
No, potatoes, plums, and chimpanzees all have the same number of chromosomes.
chromatid
Notice that the chromosome consists of two identical halves. Each half of the chromosome is called a chromatid.
sex chromosomes
Sex chromosomes are chromosomes that determine the sex of an organism, and they may also carry genes for other characteristics.
Contrast sex chromosomes with autosomes.
Sex chromosomes determine the sex of an organism and other characteristics. All of the other chromosomes in an organism are called autosomes.
haploid cells
Sperm cells and egg cells are haploid cells, which contain only one set of chromosomes.
histones
The DNA in eukaryotic cells wraps tightly around proteins called histones.
Using Table 8-1, list the haploid and diploid number of chromosomes for each organism.
The diploid number of chromosomes is given in Table 8-1. Students should divide that number by 2 to calculate the haploid number of chromosomes.
chromatin
The less tightly coiled DNA-protein complex is called chromatin.
