DNA and Chromsomes. Key Concept. Chromosomes are coiled up “packages” of DNA. Case Study. Listen to the following case study about Colin Pitchfork taken from “What is Life?” by Jay Phelan. DNA and CHROMOSOMES. When cell is about to divide, DNA coils up into CHROMOSOMES . - PowerPoint PPT Presentation
Dna, Dna replication, and cell division (mitosis and
Meiosis)
DNA and Chromsomes
Key ConceptChromosomes are coiled up packages of DNA.
Case StudyListen to the following case study about Colin
Pitchfork taken from What is Life? by Jay Phelan.
DNA and CHROMOSOMESWhen cell is about to divide, DNA coils up
into CHROMOSOMES.Each section or piece of the DNA called a GENE-
strand codes for a specific protein, that carries out a cellular
function.These chromosomes will double, or replicate, right before
cell division.
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5Each chromosome consists of 2 identical copies (the original
chromosome and the replicated chromosome) called CHROMATIDS.The 2
chromatids are connected at the point called the CENTROMERE.
6NUMBER OF CHROMOSOMESEach species has a specific number of
chromosomes.Organisms have 2 (a pair) of each chromosome (i.e. pair
#1, #2, #3, etc).Called HOMOLOGOUS CHROMOSOMES-chromosomes that
cover the same information, but are different versions; one is
inherited from mom and one is inherited from dadThe two homologous
chromosomes, one from mom and one from dad, together are referred
to as a HOMOLOGOUS PAIR.
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