The biomolecules and organelles of the eukaryotic cell Flashcards
Importance of organelles
crucial to the structure, homeostasis and metabolism of living organisms
Function of the nucleus
Contains most of the cells DNA
The cells control center
DNA replication, transcription and RNA precessing all take place here
Dreicts protein synthesis by synthesiszung mRNA according to instructions provided by DNA
DNA structure
DNA is packed into multiple chromosomes
Each chromosome contains one long DNA molecules associated w many proteins such as histones
Histones
Package DNA intro structural units → nucleosones
The main protein of chromatin
Chromatin
Combination of DNA and protein which makes up the contents of the nucleus
What chro,osomes are made of
Nucleosomes
One of the main structures that help keep our DNA folded up neatly and packed away
Also help unfold it
Nucleolus
Dense structure in wich ribosomal RNA (rRNA) is synthesized
In the cells nucleus
Produces and assemble ribosomes
Nuclear envelope
A double phospholipid membrane that encases the nucleus
Pores allow info to defund into the nucleus
Transport of various molecules
Nucleic acids function
Nucleic acids store and transmit hereditary (genetic) information, i.e. the ‘code of life’
DNA and RNA
Purin
Adenin and Guanine
Pyrimidines
Cytosine and Thymin
A bonds to
T or U
C bonds to
G
Chemical difference between RNA and DNA
DNA: H→ 2- desoxyribose
RNA: OH at 2nd C→ ribose
Nucleotide structure
Nitrogenous base → a, c,g, t,,u
Sugar
Phosphate group
How is the nucleotide chain strcutured
DNA chain is antiparallel and complementary and double stranded
Antiparralel
the strands run in opposite directions, parallel to one another
3-5 and 5-3
Complementary
Base pair on one strand matches to the pase pair on the other
Double stranded
DNA consists of two strands that are held together thru hydrogen bonds (WBB)
A-T → 2 bonds
C-G → 3 bonds
The strands are complementary and antiparallel
The endoplamic reticulum (ER)
Network of enclosed structures
Is continuous w nuclear envelope
SER
RER
mRNA
The genetic code is transferred via mRNA to the cytoplasm, where ribosomes translate the code into proteins
Messenger RNA
The endomembrane system
ER
SER
RER
Golgi apparatus
Lysosomes
SER Function
No ribosomes on outer surface
Synthesizes lipids, metabolism, carbs etc
Lipids
Group of compounds that mix poorly or if at all with water
Fats → constructed from glycerol and 3 fatty acids
Phospholipids → transport between membranes
Steroids
function as energy source (fats), membrane components (phospholipids and cholesterol) or hormones (steroids)