Cell Signaling
Name the four kinds of cell receptors.
G protein coupled receptors, receptor tyrosine kinase, ligand gated ion channel, and steroid hormone receptor
Name the three reasons cells divide
Reproduction, growth & development, tissue renewal
What is the end result of Meiosis 2?
4 genetically different/ unique daughter cells
Define phenotype and genotype
Phenotype - observable characteristic
Genotype - Genetic identity or genetic makeup of an organism
What is the difference between benign and malignant
Malignant tumors will grow rapidly and spread to other parts of the body while benign are still cancerous but grow slower and will not spread
Name the three steps of cell signaling.
Reception, transduction, response
Name the function of interphase and prophase
Interphase - Growth and development, DNA replication
Prophase - chromatin condenses, early mitotic spindle, prep for division
When does crossing over occur and what is crossing over?
Prophase 1 and it is when chromosomes do a genetic exchange
Define dominant versus recessive alleles
Dominant - an allele that is fully expressed in the phenotype, even when other alleles are present
Recessive - an allele which is not expressed in the phenotype unless two copies are present in the organism
Name a type of autosomal dominant disorder
Achondroplasia, Polydactyly, Huntington's Disease, Marfan's Syndrome, Progeria
What is the purpose of the phosphorylation cascade?
They amplify a signal by sequentially activating multiple protein kinases, each phosphorylating multiple substrates, thus creating a larger signal from an initial stimulus.
What happens in metaphase of mitosis
chromosomes line up in the middle of the cell with the help of kinetochores and microtubules
What is a tetrad?
2 chromosomes - one from mother and the other from the father
Define homozygous versus heterozygous
Homozygous - 2 identical alleles of a particular gene
Heterozygous - 2 different alleles of a particular gene
Name a type of autosomal recessive disorder
Tay Sachs, Sickle Cell, Cystic Fibrosis
What is the role of cAMP as a second messenger?
cAMP relays signals from receptors to intracellular targets, often activating protein kinase A
what happens in anaphase and telophase
Anaphase - chromosomes are pulled apart toward opposite poles of the cell
Telophase - nuclear membrane starts to form and cleavage furrow forms. cytoplasm splits
What is the purpose of meiosis?
to produce egg and sperm cells, for reproduction and genetic variation.
What does Mendel's Law of Independent Assortment state?
homologous chromosomes are randomly distributed at the metaphase plate such that a mixture of maternal and paternal homologous assort to each gamete
Name ALL of the kinds of X linked disorders mentioned in this class
color blindness, Duchenne muscular dystrophy, hemophilia
How does Herceptin work?
Herceptin targets the HER2 receptor on cancer cells, blocking its activity and slowing the growth of HER2-positive tumors
At each check point, what is being checked?
G1 - Check for nutrients, growth factors, and DNA damage
M - Check for chromosome spindle attachment
G2 - check for cell size and DNA replication
When do cells become haploid?
After metaphase 1 or in anaphase 1
What does Mendel's Law of Segregation state?
When gametes form, homologous chromosomes separate and are distributed to different gametes, making it so every gamete only receives one of the pair
What are the four unusual features of cancer cells
Replicative Immortality
Unusual Karyotype
Abnormal Cell Surface
Ignore density-dependent inhibition of growth