Cell Cycle and Protein Synthesis Flashcards
What is the monomer of dna
nucleotide
What are the three parts of the monomer?
A sugar molecule, phosphate group and nitrogenous base
What type of bond holds the sugar and phosphate backbone together?
Phosphodiester
What are the four nitrogen bases in DNA?
ATGC
What type of bond holds the nitrogen bases together?
Hydrogen Bonds
What is meant by anti parrallel
A term used to describe the opposite orientations of the two strands of a DNA double helix; the 5’ end of one strand aligns with the 3’ end of the other strand.
Describe how the structure of DNA allows it to replicate accurately.
Because each strand of DNA contains a sequence of nucleotides that is exactly complementary to the nucleotide sequence of its partner strand, each strand can act as a template, or mold, for the synthesis of a new complementary strand
If all of your cells have the same DNA, how is it that you have different types of cells in your body?
Because they are located in different parts of your body.
b. Because different types of cells use different pieces of the same DNA.
c. Because the noncoding DNA behaves differently in different cell types.
d. Because while all cells in your body may have the same DNA, they have different genomes.
What is the purpose of cell division?
for growth and the maintenance and repair of cells and tissues
Why do cells need to divide in order for an organism to grow?
In order for organisms to grow, body cells either have to increase their size or divide. Most cells divide, because smaller is better when it comes to cells.
DNA
DNA’s unique structure enables the molecule to copy itself during cell division.
Centromere
helping the cell divide up its DNA during division
Chromosomes
ensures DNA is accurately copied and distributed in the vast majority of cell divisions.
Chromatin
Helps to prevent DNA damage
Sister Chromatid
pass on a complete set of chromosomes to all the daughter cells formed as a result of cell division.
After a cell goes through cell division, how do the chromosomes of the resulting cells compare to the original cell?
The dividing of the DNA ensures that both the “old” cell (parent cell) and the “new” cells (daughter cells) have the same genetic makeup and both will be diploid, or containing the same number of chromosomes as the parent cell.
What is the purpose of interphase?
it grows, replicates its chromosomes, and prepares for cell division.
What are the phases of interphase? (include their order
G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth).
What is the purpose of M phase?
Cell divison
What are the phases of M phase and what is their order?
prophase, metaphase, anaphase, and telophase
What is the purpose of mitosis?
growth and repair
What is the purpose of Cytokinesis?
to physically separate a mother cell into two daughter cells.
What are the three major checkpoints?
the G1/S checkpoint, the G2/M checkpoint, and the spindle assembly checkpoint (SAC).
Why are checkpoints important for the cell cycle?
monitor the order, integrity, and fidelity of the major events of the cell cycle.
What happens when the cell cycle checkpoints stop working properly
cells that are not replicating correctly will be allowed to continue to grow and multiply.
What distinguishes cancerous cells from normal cells?
Normal cells follow a typical cycle: They grow, divide and die. Cancer cells, on the other hand, don’t follow this cycle. Instead of dying, they multiply and continue to reproduce other abnormal cells.
What is the monomer of nucleic acid?
nucleotides
What are the differences between DNA and RNA?
RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.
What are the base pairing rules?
adenine (A) and thymine (T) pair together, and cytosine (C) and guanine (G) pair togethe
What is the purpose of a start codon?
marks the site at which translation into protein sequence begins,
What is the purpose of a stop codon?
signals a halt to protein synthesis in the cell.
What factors control cell growth?
Tumor Suppressors
Proto Oncogenes
Substitution
a type of mutation in which one nucleotide is replaced by a different nucleotide.
Example- GCG- GTG
Deletion
A whole new amino acid is added, or one is
missing from the mutant proton:
Example: GTGGTCCGAAACACC –– GTGGTCTGCCGAAACACC
Val-Val-Pro-Asn-Thr Val-Val-Cys-Pro-Asn-Thr
Insertion
A whole new amino acid is added, or one is
missing from the mutant proton:
Example: GTGGTCCGAAACACC –– GTGGTCTGCCGAAACACC
Val-Val-Pro-Asn-Thr Val-Val-Cys-Pro-Asn-Thr
Silent
When a base pair is substituted but the change still codes for
the same amino acid in the sequence:
Example: TCT and TCC both code for the amino acid Serine
Missense
A genetic alteration in which a single base pair substitution alters the genetic code in a way that produces an amino acid that is different from the usual amino acid at that position
Nonsense
a change in DNA that causes a protein to terminate or end its translation earlier than expected.
Frame shift
When a deletion or insertion results in a different base pair being
the beginning of the next codon, changing the whole sequence of amino acids
Example: GTGGTCCGAAACACCT –– GTGGTCGAAACACCT
Val-Val-Pro-Asn-Thr Val-Val-Glu-Thr-Pro
what is a mutation
a change in the DNA sequence of an organism.
Which type of mutation(s) is(are) potentially the most damaging? Why?
Frameshift mutations are generally much more serious and often more deadly than point mutations. Even though only a single nitrogen base is affected,
Nonsense
DNA Replication
- The dna is straightened by the topoisomerase
- Unwinding the of the dna by the helicase
- Next primase synthesizes a short rna primer on each of the strands. This provides a starting point for dna polymerase
- DNA polymerase only adds nucleotides to the 3’ end of the existing strands so it works from a 5’ to 3’ direction
- Leading strand is synthesized continuously in the 5’-3’ direction
- The lagging strand is synthesized into short okazaki fragments. The fragments are joined together by ligase.
What is the overall purpose of transcription?
which information from a gene is used to construct a functional product such as a protein. The goal of transcription is to make a RNA copy of a gene’s DNA sequence. For a protein-coding gene, the RNA copy, or transcript, carries the information needed to build a polypeptide (protein or protein subunit). Eukaryotic transcripts need to go through some processing steps before translation into proteins.
where does transcription occur
nucleus
What is the overall purpose of translation?
In this stage, the mRNA is “decoded” to build a protein (or a chunk/subunit of a protein) that contains a specific series of amino acids
Where does translation take place? Why?
Translation takes place on ribosomes in the cell cytoplasm
Prophase
DNA condenses into a chromosome
Centrosomes form spindle
metaphase
Chromosomes line up at the equator of the cell
Anaphase
sister chromatids are pulled apart
centromeres split
Telophase
DNA uncoils into chromatin
Cleavage furrow forms
Nuclear envelope reforms around dna
G1
Period of cell growth before DNA duplication
Period when interphase ends in the parent cell
S
Period when DNA is duplicated
forms two daughter cells
G2
Period after DNA is duplicated
Period when interphase begins in a daughter cell
Cytokinesis
Event that forms two daughter cells
