Presentation on theme: " Journal: Where is DNA found inside a cell?. Usually DNA inside the nucleus is wrapped around proteins to form an ‘X’ shape These ‘X’ shaped coils."— Presentation transcript:
Usually DNA inside the nucleus is wrapped around proteins to form an ‘X’ shape These ‘X’ shaped coils of DNA are called chromosomes
Why is DNA coiled up and not just a big clump in the nucleus?
P arm: Short arm of the chromosome Q arm: Long arm of the chromosome Centromere: midpoint where the two sides of the ‘X’ cross
Two identical halves of a single replicated chromosome Contain the same DNA on each half
The same for each cell in the body, except sex cells which only have half a set of chromosomes. Each individual has the same number of chromosomes their entire life The number of chromosomes is the same across an entire species.
OrganismChromosome numbers Human46 Chimpanzee48 House Mouse40 Corn20