Term | Definition |
Why do Cells divide? | - growth and repair |
Why do cells grow in numbers and not size? | - cells need to pass large volumes of materials across a membrane. The larger the cells, the less efficient |
DNA Overload | - when there are too many demands (due to the fact a cell is so large) the DNA cannot process these demands |
Binary Fission | - simpler type of meiosis for bacterial cells |
Sister Chromatids | - replicated chromosomes (exactly the same) |
Homologous Chromosomes | - chromosomes that code for the same traits but aren't genetically identical |
Goal of Mitosis | - cells to divide for growth and repair |
How do daughter cells compare to original parent cell? | - identical to one another |
Somatic vs. Gametes | s=normal g=sex cells |
Diploid Cells vs. Haploid Cells | d=2n h=n |
What are cell cycle checkpoints? | - they make sure the cell is prepared to enter the next phase |
Internal Regulators of the Cell Cycle | - if chromosomes are replicated
- if spindle fibers are attached |
External Regulators of the Cell Cycle | - if the growth factors bind
- cell to cell contact |
Apoptosis | - if a cell doesn't pass a certain checkpoint, it goes through regulated cell death, and pops |
Tumors | - mass of cells that wont stop dividing |
Benign Tumors | - abnormal cells remain at the site causing a lump |
Malignant Tumors | - spreads, displaces tissue, interrupts organ function |
Metastasis | - spread of cancerous cells via the circulatory system (Very Dangerous) |
Oncogenes and Protooncogenes | - normal role: Gas
- recessive |
Tumor Suppressor Genes | - normal role: brake
- dominant |
Radiation | - affects the cells that divide that are damaged, but not as much the normal cells |
Chemotherapy | -attacks the cells that go through mitosis |
Independent Assortment | - creates random sets of chromosomes in gametes because chromosomes separate independently of one another when reproductive cells develop |
Haploid | - one set or half the number of chromosomes |
Diploid | - 2 sets of chromosomes or full amount of chromosomes |
Random Fertilization | - since fertilization is random, it has many possible gamete possibilities due to independent assortment |
Crossing Over | - occurs during prophase 1
-homologous chromosomes pair with each other and exchange segments of genetic material
- these new chromosomes are called recombinant chromosomes |
Tetrad | - formed when homologous chromosomes come together during Prophase 1 to perform crossing over |
Non-disjunction | - failure of chromosomes to separate properly (anaphase 1) |
Somatic Mutaions | - occurs in non-germline tissue
- non inheritable |
Germline Mutations | - occurs in germline tissue (egg/sperm)
- inheritable |
Law of Dominance | - dominant alleles are expresses over recessive alleles |
Law of Independent Assortment | - every allele separates into gametes independently of eachothers |
Law of Segregation | - each gamete contains only one allele |
Monohybrids are... | - a cross between 1 trait |
Dihybrids are... | - a cross between 2 traits |
Incomplete Dominance | - one allele is not completely expressed over the other "blend"
- How to write: "dominant" R, "recessive" R' |
Co-dominance | - when a heterozygous genotype expresses both phenotypes
- how to write: H^R H^W |
Multiple Alleles | - one gene can have many possible alleles ex: Blood |
antigen | - substance able to stimulate an immune system response located on the outside of a red blood cell |
antibody | - protein made by the immune system that binds to antigens and renders it harmless |
Universal Donor (blood type) | O- |
Universal Recipient (blood type) | AB+ |
Which blood types can donate and receive? | Donate to: Receive from:
A A, AB A,O
B B,AB B, O
AB AB AB, A,B,O
O O, A,B,AB O |
Apply Multiple Alleles and Co-dominance to blood typing | Multiple alleles: there are 4 different blood types, represented by multiple alleles (I^A, I^B, i)
Codominance: 2 phenotypes can be shown at once (ex: AB) |
Polygenic Traits | traits that are controlled by multiple genes
ex: skin color, eye color, height |
Pleiotropy | one gene that codes for multiple traits
ex: PKU, Marfan syndrome, hemophilia |
Sex Linked Traits | traits controlled by genes located on the sex chromosomes
(usually X) |
X-Linked Traits - significance on males | - Y chromosome doesn't have a locus for traits therefore the males phenotype is completely dependent on the mother's genotype |
Gene Linkage | - tendancy of certain alleles to be inherited together |
Difference between gene linkage and crossing over | linked together=inherited together
- not going to cross over
- no independent assortment |
Linked Genes vs. Crossing Over | -chromosomes can have both types
- some will stay linked
- some will cross over
- genes close together generally stay linked
- we see re-combinations from crossing over when genes are far apart |
Recessive Epistasis | the recessive genotype controls the other genotype
Ex: Labs
- Color Gene 1: Represented by B
B = Black
b = Brown
Color Expression Gene 2: Represented by E
E = Will express color
e = Will not express color |
2 most important ways genetic variation happens in cells | - independent assortment
- crossing over
- NOT RANDOM FERTILIZATION |
Rh Factor | - follows traditional mendelian genetics
- + is dominant |