DNA

deoxyribonucleic acid

a chemical molecule that contains instructions needed by the cell to produce proteins. it is found in the nucleus and regulates all cell functions

a supercoiled length of DNA that has been wrapped around histone proteins

a section of DNA that codes for a specific protein and therefore a specific characteristic

a DNA molecule is a double helix shape. it is made up of nucleotides that consist of a deoxyribose sugar, phosphate group and nitrogenous base. the nitrogenous bases are joined together by hydrogen bonds

DNA is wrapped around histone proteins. when a length of DNA has been wrapped around 8 histones, that structure is collectively called a nucleosome. many nucleosomes would tightly together form a thick visible length of condensed DNA, now called a chromatin. a chromosome is made up of a long single length of this chromatin

37 and they are all related to mitochondrial function

helicase breaks hydrogen bonds between nitrogenous bases to separate DNA strands

nuclear DNA is found in the nucleus and mitochondria DNA is found in the mitochondria. nuclear DNA is a double helix shape and mitochondrial DNA is circular. nuclear DNA contains both maternal and paternal DNA and mitochondrial DNA contains only maternal

DNA polymerase binds to each strand of DNA

DNA polymerase adds free floating nucleotides according to base pair rule as it moves along strand

it means that one strand is new and one strand is old in each DNA length produced

ribonucleic acid

DNA is double stranded and RNA is single stranded

DNA has deoxyribose sugar and RNA has ribose sugars

DNA has adenine-thymine and guanine-cytosine and RNA has adenine-uracil and guanine-cytosine

DNA is very long and codes for many genes while RNA is short and only codes for one gene

messenger RNA and transfer RNA

it forms in the nucleus using the DNA code and moves to the cytoplasm where it binds to a ribosome and has instruction to make a protein

located in the cytoplasm and brings individual amino acids to ribosome during translation stage of protein synthesis

RNA polymerase binds to promoter sequences of gene to break the hydrogen bonds, separating the strands of DNA. RNA polymerase then reads the template DNA strand adding free RNA nucleotides according to complementary base pair rule. the mRNA molecule then moves from the nucleus through the nuclear pores to the ribosomes in the cytoplasm.

mRNA attaches to ribosomes ( a sequence of three bases is called a codon and determines which amino acids needs to be put in place ). the amino acids are taken to the ribosome attached to a tRNA molecule, each tRNA molecule has a set of three nucleotides called an anticodon (specific to a codon). amino acids are joined by peptide bonds, forming the correct protein

the study of changes in organisms caused by modification of gene expression rather than alteration of genetic code itself

addition of a methyl group usually to a cytosine nitrogenous base. causes DNA to condense preventing transcription of DNA portion, repressing gene expression