Final answer:
Chromosomes are classified by their centromere location: 1. Metacentric, 2. Submetacentric, 3. Acrocentric, and 4. Telocentric. Human chromosomes are organized in a karyotype by size and identified by number, centromere position, and banding pattern. Sister chromatids are connected at the centromere, which plays a key role during mitosis.
Step-by-step explanation:
Chromosomes are classified into four types based on their centromere location: 1. Metacentric (the centromere is near the middle); 2. Submetacentric (the centromere is slightly off center); 3. Acrocentric (the centromere is closer to the end than to the center); and 4. Telocentric (the centromere is at one end).
In a human karyotype, autosomes are arranged according to size and identified by their number, size, centromere position, and banding pattern. The short arm of a chromosome is termed 'p' (for "petite"), and the long arm is termed 'q'. These arms can be further subdivided to describe specific locations on the chromosomes, aiding in consistent representation in the scientific literature.
During DNA replication in the S phase of interphase, chromosomes are composed of two linked sister chromatids, with the centromeric region being highly condensed and visible under a light microscope as a constricted area. This centromere contains proteins known as kinetochores, which are crucial during mitosis for spindle attachment.