The structure and organization of chromosomes in the cell Flashcards
(30 cards)
what is the shape of DNA ?
twisted ladder called double helix
What is dna made of :
made of a sequence of 4 smaller molecules called nucleotides
what is a chromosome:
A piece of double stranded DNA with its own unique nucleotide sequences
How is the DNA place in a chromosome :
it is folded and compacted byt he cell, allowing it to fit in the nucleus and be easier to organize during cell division.
what protein does dna use to be compacted
Histones
the combination of dna and proteins are called what?
Chromatin
Chromosomes can be found in an extended form during interphase but condensed for what phase :
Mphase
Gene locus :
the specific physical location on a chromosome where a given gene can be found
Centromere :
A region of very compacted chromatin on a chromosome that connects the P-arm (shorter ) and the Q-arm (longer) of the Chromosome
telomere :
repeated nucleotides at the end of the chromosome that provent the DNA from getting shorter and the ends of different chromomes from attaching .
What is the shape of a DNA molecule?
Twisted ladder, called double helix
What are the building blocks of DNA called?
Nucleotides
What is a chromosome?
A piece of double stranded DNA with its own unique nucleotide sequence
How is DNA compacted in the cell?
Using special proteins called histones
What is the combination of DNA and protein called?
Chromatin
In which phase can chromosomes be found in an extended form?
Interphase
What is a gene?
A sequence of DNA nucleotides that encodes the information required to make one type of protein
What does the term ‘gene locus’ refer to?
The specific physical location on a chromosome where a given gene can be found
What is a centromere?
A region of very compact chromatin on a chromosome that connects the P arm and Q arm
What is a telomere?
Repeated nucleotides at the end of the chromosome that prevent DNA from getting shorter
What are sister chromatids?
Duplicated chromosomes that are identical to each other
How many different types of chromosomes do humans have per cell?
23 different types
What distinguishes one type of chromosome from another?
Having a different set of genes
What are homologous pairs?
Pairs of chromosomes that contain similar genes arranged in the same order
