Mendelian Genetics Flashcards

3468335872	What are the dominant models of inheritance in the early 19th century?	Blended inheritance: hereditary material is mixed in the offspring, once DNA is mixed, it can't be separated Inheritance of acquired characteristics: parents can modify their traits based on use and can be passed on to their offspring	0
3468364127	Who developed the particulate theory of hereditary? And what does it state?	Gregor Mendel. He proposed that parents pass on hereditary factors (genes) that remain distinct from generation to generation.	1
3468392924	What made Mendel's work successful?	He studied traits that were qualitatively different and characters that only had 2 possible forms. He also kept very accurate, quantitative records of his work.	2
3468451654	What is true breeding?	Crossing organisms who either have two dominant or two recessive alleles.	3
3468476502	Which theory did Mendel prove wrong with his first experiment?	Theory of blended inheritance. In his first experiment, Mendel crossed true-breeding parents (a purple flower and a white flower) and the offspring were all purple, proving that DNA can be separated.	4
3468513718	What did Mendel proposed about alleles?	1. Heritable factors (genes) have alternate versions that specify traits 2. Offspring receives 2 alleles per trait, one from the mom and one from the dad. (Homozygous and heterozygous) 3. For 2 different alleles, one will be dominant which expresses the trait, and one will be recessive which carries the trait.	5
3468555583	What did Mendel's principle of segregation state?	Character traits are determined by the combination of genes on homologous chromosomes. The 2 alleles for each character trait are separated during gamete production (anaphase) and reunited during fertilization	6
3468606847	After crossing two heterozygous plants, what did Mendel conclude about their genotype and phenotype?	There was a 3:1 dominant to recessive phenotype and 1:2:1 genotype.	7
3468619623	What principle did Mendel's dihybrid cross lead to?	Independent assortment. Segregation of alleles for one trait are independent of the segregation for a second trait. This is due to the random alignment of homologous chromosomes during metaphase.	8
3468676340	For _____________ genes, all possible gametes will be produced in ______________ numbers via meiosis.	unlinked, equal	9
3469058700	When genes are linked, recombinant gametes can only be produced through _________________ .	crossing over (during prophase I of meiosis)	10
3469066326	What happens during crossing over?	Chromatids of homologous chromosomes break and recombine. It is a reciprocal exchange of genetic material and occurs randomly.	11
3469092840	Frequency of recombination is _____________ to the distance between two genes and can be used to _________ the relative positions of genes on a chromes.	proportional, map	12
3469126958	Does the presence of a X or Y chromosome determine the sex of the child?	Y	13
3469135950	Since makes can't be heterozygous for x-linked alleles, they are considered _________________ dominant or ______________ recessive.	hemizygous	14
3469158415	What is incomplete dominance?	This happens when a heterozygote has an intermediate phenotype. Some gene products are present in limiting quantities and are thus expressed less than a homozygous dominant would.	15
3469172148	What does polygenic inheritance state?	Many traits are determined by the combination of multiple genes.	16
3469184489	For some traits both ________________ and ___________________ influence phenotype.	genotype and environment.	17
3469194111	What is the benefit of pedigree analysis?	It allows you to trace one's family inheritances and allows prediction of how it will affect future offspring.	18
3469207970	What are some autosomal recessive disorders?	Tay-Sachs disease, cystic fibrosis, sickle cell disease.	19
3469229654	What is the cause of Tay-Sachs disease?	It is due to a mutation of in HEXA gene that encodes lysosomal enzyme. This leads to a build up of fatty acid gangliosides in the brain and will be fatal.	20
3469264893	Approximately how many European Americans are carriers of cystic fibrosis disease, making it one of the most common fatal diseases in the US?	1/25.	21
3469270442	Cystic fibrosis is due to what kind of autosomal mutation and what are the effects of it?	It is due to a CFTR mutation on chromosome 7 that increases mucus in the lungs due to high levels of extracellular chloride ions.	22
3469284728	What is sickle cell disease?	It is when the red blood cells are abnormally shaped which can clog blood vessels.	23
3469292853	What causes sickle cell disease?	It is due to a beta-hemogoblin mutation on chromosome 11.	24
3469310340	Name two types of dominant inherited disorders	Huntington's Disease, achondroplasia (dwarfism), familial long QT syndrome	25
3469324527	What causes Huntington's disease and what are the effects of it?	It is due to a mutation on the Huntington gene. This diseases causes a loss of motor control, cognitive problems, and dementia. It usually strikes individuals between 35-45 years old.	26
3469340932	Some mutations _______________ a specific disease but some _________________ an individual to a disease.	cause, predispose	27
3469345926	_______________ and ______________ also contribute to diseases.	Lifestyle, environment	28
3469361548	Both BRCA 1 and BRCA 2 are what type of genes?	They are tumor suppressor genes that encode proteins involved in DNA repair.	29
3469376340	What are the possible outcomes of genetic testing?	1. Identification of known mutations in the gene are found 2. No mutations in the gene are found 3. There are parts of the gene that are unidentified	30
3469408819	What is the QT syndrome and what can trigger it?	It is a heritable heart rhythm disorder than can cause fainting spells or sudden death. This is usually triggered by emotional or physical stress.	31