Review of Prokaryotic and Eukaryotic Cells Flashcards
Eukaryotic cells
4 points
They have a membrane bound nucleus
They have membrane bound organelles
Can be multicellular or unicellular
Most organisms are eukaryotic such as Animals, plants, fungi, insects
Prokaryotic cells
4 points
No membrane bound nucleus
No membrane bound organelles
Are unicellular
Bacteria are the main group
DNA structure
3 points 😱
DNA is a nucleotide chain (a polynucleotide)
Double helix made of a sequence of complementary nitrogenous bases
The bases are joined by weak hydrogen bonds
and are attached to a sugar phosphate group
DNA stores and transmits genetic information - it functions in the same way all living things do
What represents this?
The Central dogma of molecular biology states that genetic information flows only in one direction, from DNA to RNA (transcription), to protein (translation), or RNA directly to protein.
What are the DNA complimentary bases called???
Spelling bee challenge 😍😍
Adenine - Thymine
Guanine - Cytosine
DNA in eukaryotes
Linear chromosomes are made up of DNA which is tightly coiled around proteins called histones
The majority of DNA in a eukaryotic cell is found within the nucleus
DNA in prokaryotes, mitochondria, and chloroplasts
single circular chromosomes, which are unbound, are made up of DNA and not bound to histones
DNA in mitochondria and chloroplasts is also circular and not bound to histones
DNA visibility - eukaryotes
2 points
DNA is not visiable with a light microscope for most of the cell cycle
When DNA becomes tightly packed into a chromosome during cell division, it is visible using a light microscope
Compare chromosomes in prokaryotes vs eukaryptes
chromosome structure, organelles, ribosomes, and DNA location
Structure:
prokaryote = one circular chromosome
eukaryotes = linear chromosomes (no. varies between species)
Organelles:
pro = none
euk = mitochondira and chloroplasts have their own circular DNA
ribosomes
pro = yes
euk = yes
location of DNA
pro = cytosol
euk = majority in the nucleus, mitochondria, and chloroplasts
Why does DNA replicate
To allow for genetic information to be inherited
Semi conservative replication of DNA
DNA is replicated by the mechanism of semi conservative replication
meaning that each DNA double helix that is produced is half old conserved and half new
Describe the process of semi conservative DNA replication
HELICASE, ELLIE, FREES, DNA POLYMERASE, EVERYDAY
Helicase - breaks the hydrogen bonds between bases and seperates the two strands of the DNA
Each - strand serves as a template for making a new strand
Free - DNA necleotides pair to the exposed bases following the complimentary base pairing rule resulting in the new strand being complimentary to the template strand
DNA polymerase - links the necleotides to the newly forming strand
Each - new double stranded DNA molecule reforms into a double helix. One strand of each new molecule is an original strand, the other is a new strand. This is why it is called semi conservative replication.
DNA
functions
It is the molecule of heredity and the means by which the nucleus controlls cell activity
DNA provides the code for the production of proteins, which are key molecules in cells that control all cell activities
