Second Week Lecture 2 Flashcards
Transcription
-Information is moved from DNA to mRNA
Translation
mRNA is read to produce proteins
Transcription (Details)
-Needs to occur because mRNA can exit the nucleus
-It is not an exact copy, but rather the complement to the DNA
-Becomes the blueprint for protein synthesis
Translation (Details)
-Each group of three bases in mRNA constitutes a codon, and each codon corresponds with a specific amino acid
-The mRNA sequence is thus used as a template to assemble-in order-the chain of amino acids that form a protein.
Cellular Respiration (Overview)
-Process of making a new cell (cell division)
-Making an identical copy without the involvement of another cell is asexual reproduction
Chromosomes (location)
Located inside of the nucleus of animal and plant cells
Chromosomes (what is it made out of)
Made of protein and a single molecule of DNA
-DNA contains the instructions that make each living thing unique.
Why are Chromosomes part of the process?
-To ensure that DNA is accurately copied and distributed in reproduction.
What do most cells contain pairs of in the human body?
-Pairs of chromosomes
What are the only human cells that do not contain pairs?
-Gametes (reproductive cells)
How many pairs of chromosomes do humans have?
-23 pairs of chromosomes (46 total)
-One copy is inherited from each parent
What are the sex chromosomes for Females and Males?
Female: XX
Male: XY
What are the parts of the Chromosome?
-Centromere
-Telomeres
Centromere
-Helps to keep the chromosome properly aligned in preparation for reproduction
-Serves as an attachment site for the sister chromatids
Telomeres
-Repetitive stretches of DNA located at the ends of chromosomes
-Functions similarly to an aglet
-Telomeres lose a bit of DNA during every division
Mitosis
Process of sorting chromosomes
Interphase
-G1
-S
-G2
When does Mitosis start?
It starts in M phase; the end of interphase
Prophase
-Nucleus will disappear
-Chromosomes now visible
-Spindle fibers (guide wires) start to form
-Centrosomes move towards opposite ends of cell
Metaphase
-Chromosomes line up at center of the cell
-Lined up on metaphase plate (imaginary line in the middle of the cell)
Anaphase
-Chromosomes split and are pulled apart from each other by spindle fibers
- It is the shortest Stage of mitosis
-Sister chromatids break apart and begin moving towards opposite poles
-At the end of anaphase, the two halves of the cells will have an equal amount of chromosomes.
Telophase
-Chromosomes are at the far end of the cells
-Spindle fibers disappear
-Nuclei reappear
-Formation of 2 Daughter nuclei
Cytokinesis
-It is the division of the cytoplasm
-Cleavage furrow pinches cell in two
Mitosis Regulation
-Checkpoints that halts mitosis if certain conditions are not met
There are three main checkpoints in Mitosis Regulation:
G1/S checkpoint
G2/M checkpoint
Metaphase/Anaphase checkpoint
G1/S checkpoint
Restriction Checkpoint: cell size, cell nutrition, DNA damage. (things should stop when there’s something wrong)
G2/M checkpoint
DNA Replication Checkpoint: improper replication or damage. (things should stop when there’s something wrong)
Metaphase/Anaphase checkpoint
Spindle Apparatus Checkpoint: attachment of mitotic spindle to all chromosomes (things should stop when there’s something wrong)
There are three kinds of Cell Types
-Labile Cells
-Stable/Quiescent Cells
-Permanent Cells
Liable Cells
Constantly proliferating
-Skin epithelial cells, gastrointestinal epithelial, salivary gland tissue
Stable/Quiescent Cells
Typically in non-dividing state but can enter cell cycle under specific stimulus
-Lymphocytes, hepatocytes
Permanent Cells
Unable to proliferate: non-dividing
-Cardiac and skeletal muscle
What does the transcription get carried out by?
-It is carried out by an enzyme called RNA polymerase and a number of accessory proteins called transcription factors
Where does Translation occur?
-It Occurs in the ribosomes
What DNA is only inherited from the egg cell?
-Only mitochondrial DNA
G1 Phase
-G1: Cell growth
S Phase
-S: Cell replicates its genetic material in preparation for mitosis (Cell division)
-G2 Phase
-G2: Cell checks duplicated chromosomes
When is Mitosis complete?
In the telophase
