Genetics - Exam 1 Vocab

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Epistasis

Back 1

Refers to the interaction of two genes which are non-allelic. It is the masking of the action of alleles of one gene by allelic combinations of another gene.

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Cyclins

Back 2

Protein complex/family which oscillates during the cell division cycle.

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Lysogeny

Back 3

State of integrated viral genome (phage) in the host genome or the state of a bacterial cell that has an integrated phage (prophage) in its chromosome.

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pseudoautosomal region/gene

Back 4

The region of the XY bivalent which synapses during mitosis/a gene that occurs on both sex-determining heteromorphic chromosomes.

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x-chromosome

Back 5

A chromosome that becomes heterochromatic in human females.

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replica plating

Back 6

Replication of bacterial colonies in similar patterns on many plates

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F or F'

Fertility Factor

Back 7

In integrated state this episome transforms bacteria into Hfr.

The plasmid that allows a prokaryote to engage in conjugation with and pass DNA into an F- cell.

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phenylalanine

Back 8

Accumulation of this aminoacid causes PKU

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crossing over

Back 9

The process which results in recombination of linked genes.

A process in which homologous chromosomes exchange parts by a breakage-and-reunion process.

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kinetochore

Back 10

The proteinaceous structure at the centromere binds microtubules.

The chromosomal attachment point for the spindle fibers, located on the centromere.

Trilamellar proteinaceous organelle superposed onto the centromere.

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Kinetochore microtubules

Back 11

Microtubules radiating from the centrosome and attached to the kinetochores of chromosomes during mitosis and meiosis.

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Karyokinesis

Back 12

The process of nuclear division.

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Cytokinesis

Back 13

The division of the cytoplasm of a cell into two daughter cells.

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Is the DNA of the lambda phage a circular molecule?

Back 14

Of course.

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homogentisic acid

Back 15

The chemical which accumlates to result in "black urine" disease.

It should degrade into maleylacetoacetic acid.

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Lyonization

Lyon Hypothesis

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The phenomenon resulting in inactivation of mammalian X(s).

The hypothesis that suggest that the Barr body is an inactivated X chromosome.

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Galactose

Back 17

The I^B gene adds to

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Heterochromatin

Back 18

Main, genetically inactive, component of Y chromosome.

Chromatin that remains tightly coiled(and darkly staining) throughout the cell cycle.

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Auxotrophic

Back 19

Bacterial strain requiring specific nutritional supplements to grow.

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Exogenote

Back 20

New Foreign DNA which enters a recipient bacteria

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Sexduction, F-Duction

Back 21

Genetic recombination mediated by the F-Factor

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Synaptonemal Complex

Back 22

A proteinaceous complex that apparently mediates synapsis during the zygotene stage and then disintegrates

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Homologous Chromosomes

Back 23

Members of a pair of essentially identical chromosomes that synapse during meiosis

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Dictyate/Dictyotene

Diplonema

Back 24

Mammalian oocytes are suspended at this stage at birth before resuming meiosis.

The stage of prophase of meiosis I in which chromatids appear to repel each other.

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Barr Body

Back 25

Inactive X chromosome found in somatic cells

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XIST

Back 26

The gene on the mammalian X which control X-inactivation

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Independent Assortment

Back 27

Independant "recombination" of two non-linked genes.

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Specialized Transduction

Back 28

First needs integration
Breaks out with one cross over
Results from cross over
Needs lysogeny

Specialized "picks up" specific region near the point of its integration.

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Generalized Transduction

Back 29

Picks up any region
Does not need integration
Doesn't crossover
Results from lytic cycle
Results from regions of just "grasping"?

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Interference

Back 30

Reduction in the frequency of occurence of a cross over in the vicinity of another cross over event

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XgA

Back 31

A gene on the mammalian X which is also present on the Y chromosome.

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Bivalent

Back 32

Structures, formed during prophase of meiosis I, consisting of the synapsed homologous chromosomes. Equivalent to a tetrad of chromatids.

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XIST, G6PD, HPRT

Back 33

Genes on the human X chromosome which exhibit hemizygosity

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somatic cell hybrid

Back 34

Most used method to assign genes on human chromosomes.

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pseudoautosomal

Back 35

The regions of XY bivalent in mammels which show pairing

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Transduction

Back 36

Genetic transfer mediated by a viral genome (particle)

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nondisjunction

Back 37

Failure of chromosomes to seperate properly during cell division

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Conjugation

Back 38

Bacterial "mating"

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Segragant Genome

Back 39

The genome that is lost in somatic cell hybrids

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Merozygosity

Back 40

The condition of being a partially diploid genome in an otherwise haploid organism.

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heteromorphic

Back 41

Decribes a pair of morphically different chromosomes like the XY bivalent

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homogametic

Back 42

An organism that produces gametes of all the same type (mammalian females, X chromosome)

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pachynema

Back 43

The stage of prophase I of meiosis in which chromatids are first distinctly visible.

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metaphase I

Back 44

When microtubules bind to the meiotic bivalents

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Inversion

Back 45

Chromosome abberation which results in sterility only if chiasmata are formed in a certain segment

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Euchromatin

Back 46

Regions of eukaryotic chromosomes that are diffuse during interphase. Presumably the actively transcribing DNA of the chromosomes

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Robertsonian Translocation

Back 47

Fusion of 2 acrocentric chromosomes at the centromere

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Restriction Transduction

Back 48

Form of transduction based upon faulty looping out by a phage carrying some neighboring loci to the attachment site.

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Ubiquitin

Back 49

Cyclosome attaches this to proteins that are being broken down.

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Cyclosome

Back 50

Anaphase-promoting complex (APC). A protein complex that breaks down cyclin B and other proteins.

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Cell Cycle

Back 51

G1, S, G2, M

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Mitosis

Back 52

Prophase, Metaphase, Anaphase, Telophase

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Meiosis

Back 53

Prophase I (leptonema - bouquet stage, zygonema, pachynema, diplonema, diokinesis) - when crossing over takes place, Metaphase I, Anaphase I, Telophase I, Prophase II, Meiosis II.

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Chiasmata/Chiasma

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X-shaped configurations marking the places of crossing over.

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Synaptonemal complex

Back 55

Appears between homologous chromosomes and mediates synapsis in an unknown way. Shows up at the beginning of prophase II

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Hemizygosity

Back 56

Condition of a gene only being present on one homolog.

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Episome

Back 57

A genetic particle of certain cells, especially bacterial cells, that can exist either autonomously in the cytoplasm or as part of a chromosome