U1 - Structure and Organisation of DNA Flashcards Preview

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Flashcards in U1 - Structure and Organisation of DNA Deck (9)
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1
Q

describe the stucture of DNA

A

DNA is a double helix with antiparallel strands

2
Q

describe the role of covalent bonds in DNA strands

A

nucleotides are joined together by covalent bonds, from the phosphate of one nucleotide to the deoxyribose of the next. This forms the sugar-phosphate backbone

3
Q

what is meant by the term prokaryote

A

an organism which lacks a true membrane-bound nucleus i.e. bacteria

4
Q

what is meant by the term eukaryote

A

an organism which has a true membrane-bound nucleus i.e plants, animals, fungus

5
Q

state the features of prokaryotic cells

A

DNA is held in the cytoplasm in a singular circular chromosome and circular plasmids; lack a true membrane-bound nucleus

6
Q

state the features of eukaryotic cells

A

DNA is held in the NUCLEUS, tightly coiled around proteins called histones into linear chromosomes; mitochondria and chloroplasts also contain circular chromosomes; eukaryotic cells have a true membrane-bound nucleus

7
Q

where is DNA found in eukaryotic cells other than the nucleus?

A

circular chromosomes can be found in the mitochondria and chloroplasts of plant + animal cells

8
Q

what is a plasmid?

A

a circular, self replicating DNA molecule which carries only a few genes

9
Q

what makes the structure of a yeast cell interesting?

A

yeast is a eukaryote but has plasmids like prokaryotes do