AP Biology: Genetics Flashcards

8304001378	Beads on a string	Nucleosome	0
8304001379	Protein that DNA wraps around	Histone	1
8304006397	String of nucleosomes	Chromatin	2
8304028881	Active chromatin	Euchromatin	3
8304028882	Silent, dense chromatin	Heterochromatin	4
8304034128	Haploid	One copy of each chromosome per cell.	5
8304034129	Diploid	Two full copies of each chromosome	6
8304035664	Polyploid	More than two full copies of each chromosome	7
8304043891	Homologous pairs	Chromosomes with the same genes in the same location, but perhaps different alleles	8
8304050900	What connects sister chromatids?	Centromere	9
8304058834	Kinetochore	Cytoskeleton fibers that attach to the centromere to ensure proper separation during mitosis	10
8304061782	Structural genes	Specific coded instructions for proteins	11
8304066088	Embryonic genes	Genes that affect the development of an embryo but turn off after birth	12
8304072592	Control regions	"Switches" to turn genes on or off	13
8304076614	Telomere	Non-coding areas at the end of each gene that shorten with each replication	14
8304102303	Parts of the interphase	G1, *G0, S, G2	15
8304106891	What takes up the most of a cell's lifespan?	Interphase, 95%	16
8304113481	G1	The cell performs its cellular function and increases in size. DNA exists as single chromosomes. Cells wait for environmental cues to divide.	17
8304119686	G(0)	G1 but cell is not waiting for cues to divide.	18
8304122220	S	DNA is replicated, resulting in chromosomes that consist of two sister chromatids made of dense heterochromatin.	19
8304142626	G2	Cell grows and produces membranes, proteins, and organelles in preparation for division	20
8304152068	Mitosis (M)	The cell is focused on properly lining up the chromosomes and dividing in two. It does not perform its cellular function at this time, and the process lasts only a few hours.	21
8304163571	2 Properties of normal cells	Contact inhibition, anchorage dependence	22
8304174278	2 Properties of cancerous cells	Grow and divide rapidly even when crowded, get loose and travel through the blood (metastasis)	23
8304181855	Cells should only divide in order to...	Grow from embryo, grow from young to adult, repair damaged cells, and produce protective structures (skin/hair/bark)	24
8304190742	G1 Checkpoint	The cell receives the signal to divide or not. This is the most vital checkpoint.	25
8304206888	G2 Checkpoint	The cell checks if it has enough nutrients & building materials as well as if each chromosome has a complete sister chromatid.	26
8304235175	M Checkpoint	The cell determines whether its chromosomes are properly lined up across the center. If not, apoptosis occurs. (metaphase of M)	27
8304250241	Cyclins	Chemicals made by the cell when growth stimuli exist and degrade after use. These accumulate during G1 and G2. Quick rise --> cell division.	28
8304261274	Things that cause an increase in cyclins	Neighboring cell dies, high growth hormone concentration, high nutrient concentration, old age of cell, long telomeres, cell type (skin? hair? etc)	29
8304272833	Things that inhibit cyclin production	Crowding of cells, low growth hormone, low nutrients, young cell age, short telomeres, cell type (neuron?)	30
8304280436	Kinases	Proteins that give the go-ahead at cell cycle checkpoints. Work by phosphorylating proteins in the cell, allowing it to perform tasks related to growth and division.	31
8304284427	Cyclin Dependent Kinases	Kinases that must bind to a certain cyclin in order to be active.	32
8304303077	MPF	Maturation promoting factor, the G2 cdk that allows mitosis to start.	33
8304310637	Cyclin Expression Cycle		34
8304313873	Tumor Suppression genes, and the best known one	Genes that force the cell to commit apoptosis if checkpoints are failed. Best known: p53, which activates DNA repair genes and inactivates certain cdks, thereby halting the cell cycle	35
8304330684	Proto-oncogenes, and the best known one	Govern go-ahead signals, including the cell's response to cdk and cyclin levels. Best known: ras, mutant versions cause synthesis of a protein inducing kinase synthesis without cyclin.	36
8304368320	Prophase		37
8304370674	Metaphase		38
8304375496	Anaphase		39
8304385493	Telophase		40
8304388937	Cytokinesis	animals: cleavage furrow, plants: cell plate	41
8304420575	Three factors that lead to genetic diversity in sexual reproduction	Independent assortment, crossing over, and mutations	42
8304426598	Reduction Division	Meiosis reduces cells from 1 diploid cell to 4 genetically unique haploid gamete cells.	43
8304438055	What is separated during Meiosis I?	Homologous Chromosomes	44
8304442242	What is separated during Meiosis II?	Sister Chromatids	45
8304448666	When does crossing over occur?	During Prophase I	46
8304489037	Crossover Point	Chiasmata	47
8304501482	When are genes not linked?	When they are on different chromosomes so they assort independently or when they are far apart so crossing over can occur.	48
8304504661	When are genes linked?	When they are close together so there is little space for a crossing over point between them.	49
8304527111	Law of Segregation and mutation exception	After meiosis I, allele pairs separate because homologous chromosomes split. Exception: nondisjunction	50
8304534388	Law of Independent Assortment	Traits (that are not close together on the same chromosome) assort independently of each other.	51
8304548499	9:3:3:1 Ratio	The expected appearance of phenotypes in a dihybrid cross: 9 dominant dominant, 3 dominant recessive, 3 recessive dominant, 1 recessive recessive	52
8304604924	Law of Dominance and exceptions	2 Alleles exist for each trait. If at least one dominant allele is present, the organism will express it. Exceptions: incomplete dominance, codominance, pleitropic genes	53
8304618010	Nondisjunction	When chromosomes fail to separate properly.	54
8304623662	Example of Incomplete Dominance	Red flower (RR) x White flower (rr) = pink flower (Rr)	55
8304625462	Example of Codominance	Red cow C^rC^r x White cow C^wC^w = Roan cow C^rC^w	56
8304636735	Pleitropic Genes	Genes that have different effects in different cells. Example: cystic fibrosis, a disease that creates a faulty CFTR chloride ion channel, which harms the function of many organ system	57
8304658583	Environmental factors that affect gene expression	Altitude, temperature, activity level, and nutrition can all change how an organism expresses its genes. For example, hydrangea flowers are different colors depending on the pH of the soil.	58
8304676405	Quantitative Characteristics	Traits that show variance along a continuum, usually because there are multiple genes involved.	59
8304679678	Polygenic traits	Traits which are determined by multiple genes.	60
8304702004	Epistasis	When one gene regulates the expression of another, so that if it is turned off, the phenotype will be a certain way regardless of the other genotype	61
8304827967	Sex Linked Trait	Found on the X Chromosome. Recessive: men inherit them from their mothers and express it more often than females because they only have one copy of the gene	62
8304852019	Barr body	X Chromosome turned off and massed. Random one for each nucleus	63