BSCI222 Unit Three

chromosome rearrangements

chromosome mutations changing structure of individual chromosomes

Segmental Duplication

partial duplications of chromosome segments, where small number of genes are affected

tandem duplication

(type of segmental duplication) duplicated segment immediately adjacent to original

reverse duplication

type of tandem duplication where duplication is inverted

dispersed/displaced duplication

type of segmental duplication where duplicated segment is distanced from the original

aneuploidy

whole duplication fo chromosome from nondisjunction in meiosis

polyploidy

when whole genome is duplicated of selected chromosomes

autoploidy

duplicated sets of homologous chromosomes

diploidization

when polyploid re-establishes bivalence

homologous genes

copies on matching pair

orthologous genes

copies on divergent pair

allopolyploidy

duplication of sets of chromosomes in hybrids

chromosome deletion

loss of chromosome segment

haploinsufficiency

unbalanced gene expression

pseudo dominance

expression of normally recessive mutations

chromosomes inversion

when a chromosome segment is inverted 180º from breakage in 2 places

paracentric

inversions not including centromere (but next to), leading to limited gene exchange and isolated sister species

pericentric

inversions including centromere

small inversion leads to…

low recombination

translocations

movement of chromatin segment

nonreciprocal translocation

type of translocation where genetic material moves from chromosome to chromosome without reciprocal change

reciprocal translocation

type of translocation with a two-way exchange between chromosomes

cell fate determination

when a totipotent cell becomes specialized

differentiation

cells losing ability to become other cells

morphogens

ligands binding to cell to create gradient determining cell fate

homeotic genes

master regulators of development that determine identity of individual segments by activating other genes for segment-specific characteristics

HOX genes

adjacent genes with homeobox for organizing segments in anterior-posterior (drosphilia)

homeobox

nucleotides for DNA binding for activating

apoptosis

cell death, when mitochondria signals deletion using cascades enzyme

antigen

molecule (protein) eliciting an immune reaction; what we don’t have in body

humoral immunity

secreted antibodies by B cells

antibodies

(immunoglobulins) proteins binding that mark antigens for destruction

B cells

a type of lymphocyte secreting antibodies

lymphocytes

white blood cell carrying out immune function

variable regions

regions on immunoglobulin arms that make antigen-binders and specify the type of antigen an antibody can bind to

cellular immunity

immune response activating (T cells and macrophages) to destroy infected cells

chromosomal DNA

protein coding DNA

plasmids

extrachromosomal DNA that carry non-essential genes and replicate independently of chromosome, help spread antibiotic resistance

episomes

a type of plasmid that replicates freely and integrates into bacterial chromosome

transformation

a method of transport where competent bacteria acquires DNA from the medium it’s grown in

competent bacteria

bacteria able to take up DNA from cell membrane

conjugation

method of transport where bacterial donates DNA to recipient bacteria

transduction

method of transport where viral DNA is incorporated from virus

virus

small RNA/DNA genome that delivers genetic material into cells with its protein coat (help)

bacteriophage

viruses injecting genetic material into bacterial cell with hosts

Lytic phase

cytoplasmic viral DNA replication where phage attaches to receptor of bacterial cell and injects DNA

Lysogenic phase

when viral DNA is incorporated into genome to make a prophage

retrovirus

an RNA genome that dodges the immune system through masking with reverse transcriptase

reverse transcriptase

makes DNA from an RNA template inserted into genome