W2 Lecture 1 27/02 Flashcards
What is the plasma membrane?
A barrier between the cell and the outside environment.
Outside the cell has..
Water & ions (sodium & chloride)
Inside the cell has…
Water, ions (potassium & phosphate), organelles (nucleus, ribosomes, ER, Golgi, vesicles, mitochondria)
What does protein synthesis determine?
The function of the cell
What are the organelles in protein synthesis?
Nucleus, ribosomes, endoplasmic reticulum, Golgi complex, transport vesicle
What does aerobic metabolism need?
O2, carbohydrates, lipids, proteins
What does aerobic metabolism produce?
ATP (for cell), CO2, H20 (and acid)
What does the nucleus do?
Contains DNA and controls the function of the cell
4 base types DNA contains?
Adenine, thymine, cytosine, guanine
Peptide =
Chain of amino acids
Endoplasmic reticulum
Folds peptide of proteins, metabolises liquid
The Golgi Complex? (3)
Process proteins, make vesicles for transport, recycle vesicles
Secretory vesicles? (2)
Bind plasma membrane, export proteins
What is DNA?
A sequence of code for a protein contained in the nucleus.
What is RNA?
A working copy of the DNA created when a protein needs to be produced.
Describe the sequence of events via which a protein is produced from DNA.
Nucleus – transcription of DNA to RNA
Ribosome – translation of RNA to peptide
ER – folding of protein
Golgi – packaging of protein to transport to destination
Genome?
Nucleus contains code for individuals proteins
Chromosomes?
Collection of genes
Regulation =
What happens to mRNA
Gene expression is regulated by?
Steroids, cellular stimuli (e.g. hormones), cell programming
Controlled by families of proteins
Control transcription, control translation
Determines cellular activity and cell types
e.g. only beta cells produce insulin, muscle cells produce high levels of actin and myosin
Each cell has 2n chromosomes
2 copies of each gene
Gene
The DNA code for an individual protein
Allele
A variant of the DNA code for a protein
Genotype
The coding variants (alleles) of a gene an individual carries
Phenotype
The characteristics an individual shows from expression of protein
Chromosomes
A collection of genes bound together
Chromosome pairs
There are two copies of each chromosome in a cell
Number of chromosomes
Humans have 23 chromosome pairs in their genome
Dominant
Only one allele necessary for phenotype to show
Recessive
Both alleles must have same characteristic for phenotype to show
Co-dominant
Alleles are different and phenotype is mix of both
Other factors in genetics
Gene interactions, regulation of expressions, environmental effects
Types of genetic disorders??
extra chromosomes, damaged chromosomes, autosomal dominant, autosomal recessive (like cystic fibrosis), X linked
Autosomal
Any chromosome other than X or Y
What are proteins coded by?
Genes
Phenotype
What shows
Genotype
What alleles an individual has
For each gene, each individual has 2 copies of the gene. Each version is called an…
Allele. If alleles are different the protein coded for may be different.