diversity of organisms ib bio

Eukaryotic genomes

Genomes vary in size and base sequence.

Genome size

Total amount of DNA in an organism.

Chromosome number

Total chromosomes present in a species.

Homo sapiens

Species with 46 chromosomes.

Pan troglodytes

Species with 48 chromosomes.

Canis familiaris

Domestic dog species with 78 chromosomes.

Oryza sativa

Asian rice species with 24 chromosomes.

Parascaris equorum

Roundworm species with 2 chromosomes.

Diploid zygote

Cell formed from fusion of haploid cells.

Chromosome pairs

Chromosomes exist in pairs in diploid organisms.

Chromosome number significance

No correlation between chromosome number and species relationship.

Gene count

Total genes present in an organism's genome.

Human genes

Estimated 23,000 genes in humans.

Chimpanzee genes

Estimated 22,000 genes in chimpanzees.

Domestic dog genes

Estimated 20,000 genes in domestic dogs.

Asian rice genes

Estimated 38,000 genes in Asian rice.

Chromosome fusing

Two chromosomes combine to form a single chromosome.

Chromosome splitting

One chromosome breaks into two smaller chromosomes.

Karyotype

Arrangement of chromosomes by size and shape.

Karyogram

Visual representation of an organism's chromosomes.

Autosome

Non-sex chromosomes in a karyotype.

Sex chromosome

Chromosomes determining the sex of an organism.

Karyotyping

Process of classifying chromosomes by characteristics.

Chromosome evolution

Changes in chromosome number can lead to new species.