V L2: Introduction to the DNA molecule Flashcards
what are the two types of nucleic acids?
DNA
RNA
what is a nucleolus ?
Ribosome-producing factory
what’s a eukaryotic cell?
Eukaryote, any cell or organism that possesses a clearly defined nucleus.
repeating pentose-phosphate units….
5’ (arrow) 3’
who stated the Double helical structure ?
Watson and Crick 1953
DNA strands are….
Anti-parallel strands
what are the 5 bases?
adenine thymine guanine cytosine uracil
what happens if you heat DNA?
Heating de-stabilises the H-bonds (denaturing)
whats temperature required to denature DNA known as?
Tm - melting temperature
whats melting temperature of DNA dependent on?
GC% of the sequence
what can you do if you have the DNA sequence of one strand?
complementary sequence can be determined
what is a autosome and how many do we have?
any chromosome that is not a sex chromosome, 22 pairs.
How many pairs fo sex chromosomes do we have?
1
males are?
heterogametic
what is Multiple mitochondrial genomes (mtDNA) ?
these DO NOT follow Mendelian genetic rules
what are cells with a full set of chromosomes known as?
diploid cells
what are cells with a half set of chromosomes known as?
haploid cells
which sex chromosome is larger?
X is larger then Y
How do X and Y chromosomes pair?
at meiosis via psuedoautosomal regions (PAR) at tips of the arms
what are a Complex of proteins and DNA that are stacked together known as?
chromatin
what size is chromatin?
30 nm fibre condensed form
when nuclear DNA is damaged, mitochondrial DNA is often?
preserved
mitochondrial DNA is what type of iheritence?
maternal
what are the 4 molecular processes ?
- Transcription
- RNA processing
- Translation
- Replication
what is the cell cycle?
mitosis cytokinesis G1 phase S phase ( DNA replication) G2 phase
what are the steps of mitosis?
prophase
metaphase
anaphase
telophase
what happens in prophase?
Chromatin begins to condense and is visible in the form of chromosomes. Spindle fibres begin to form as well as centrioles.
what happens in metaphase?
Chromosomes line up on mitotic spindle. Chromosomes are attached to spindle forms on opposite sides
what happens in anaphase?
sister chromatids separate from each other and are pulled towards opposite ends of the cell.
what happens in telophase?
mitotic spindle is broken down
Two new nuclei form, one for each set of chromosomes. Nuclear membranes and nucleoli reappear.
The chromosomes begin to decondense
what are the two steps of protein synthesis?
- transcription (DNA copied to RNA)
2. followed by translation (RNA template for the synthesis of a protein)
what is meiosis ?
A specialised nuclear division producing haploid cells, reducing the chromosome number by half
The information contained in the ____ in the ___ is transcribed into _____ and the _____ contained in the mRNA are translated into an _____ ____ _____.
- genes
- DNA
- mRNA
- codons
- amino acid sequence
what can a change in gene do?
change ether function of a protein
why are proteins useful in forensics?
Proteins can be studied to identify differences in individuals
why is RNA useful forensics?
Cells from different biological sources can be identified using RNA
