Mendelian Genetics Flashcards
the division of the cytoplasm
Cytokinesis
Compare + Contrast:
Mitosis vs. Meiosis
BOTH –> nuclear division
MITOSIS –> occurs in all body cells to produce somites which are cells identical to parent cell
MEIOSIS –> occurs is gonads to produce gametes which are cells unlike the parent cell
body cells
somites (somatic cells)
sex cells (egg + sperm)
gametes
Cell Cycle:
Interphase
- when cell is NOT dividing (90-95% of cycle - most of time)
* NOT a step of nuclear division
Compare + Contrast:
G1 vs. S vs. G2
ALL –> stages of Interphase
a. G1 - (gap-1) daughter cell doubles in size (grows to size of parent cell)
b. S - (synthesis) chromatin replicates
c. G2 - (gap-2) growth occurs, centrioles replicate; anticipating nuclear division
STAGES OF MITOSIS:
a. Early + Late Prophase
b. Metaphase
c. Early + Late Anaphase
d. Early + Late Telophase, Cytokinesis
STAGES OF MITOSIS:
1. Early + Late Prophase
EARLY:
- spindle forms
- no nuclear membrane
LATE:
- chromosomes move inward
- no nuclear membrane
3D array of fibers which are transport vehicles for chromosomes
Spindle / Spindle Fibers
Compare + Contrast:
Kinetochore vs. Non-Kinetochore
BOTH –> spindle fibers
KIN –> spindle fibers that DO contain chromosomes
NON-KIN –> spindle fibers that do NOT contain chromosomes
Compare + Contrast:
Chromosomes vs. Chromatids vs. Centromere
ALL –> involved in nuclear division in mitosis + meiosis
CHROMOSOMES –> one chromosome made up of two chromatids
CHROMATIDS –> two chromatids make up one chromosome
CENTROMERE –> place where two chromatids attach
STAGES OF MITOSIS:
2. Metaphase
chromosomes align at the midline of spindle
STAGES OF MITOSIS:
3. Early + Late Anaphase
EARLY:
- only haploid event in mitosis
- chromosomes break apart into chromatids
LATE:
*chromatids move apart and replicate into chromosomes
STAGES OF MITOSIS:
4. Early + Late Telophase
EARLY:
*chromosomes reach the poles
LATE:
- nuclear membrane forms
- chromatin material
- midline constriction
- CYTOKINESIS –> contents of cell split equally between cells (@ end of late telophase)
DIFFERENCES IN MEIOSIS STAGES:
Prophases I
- synapsis (alignment) of homologous (same set) chromosomes
* chiasmata occurs (crossing over)
the alignment of chromosomes
synapsis
occurs in prophase I of meiosis
paired chromosomes in sets of two that carry same traits and are located at same place
homologous chromosomes
crossing over; the exchange of genetic material
chiasmata
a cell that divids by meiosis to form gametes
meiocytes, gametocytes
Compare + Contrast:
Chromatids vs. Tetrad
BOTH –> contain genetic material, relate to chromosome make-up
CHROM –> two chromatids make up one chromosome
TETRAD –> group of four chromatids make up one set of homologous chromosomes
DIFFERENCES IN MEIOSIS STAGES:
Anaphase I + Anaphase II
ANAPHASE I:
*reduction division
ANAPHASE II:
*equatorial division
Compare + Contrast:
Reduction division vs. Equatorial division
BOTH –> occur in anaphase stage of meiosis
RED –> tetrads separate into duplicated chromosomes
EQU –> duplicated chromosomes separate into chromatids (single chromosomes)
sex
syngamy
1st diploid cell, formed by fertilization of haploid sperm + egg during syngamy
zygote
Compare + Contrast:
Gametes vs. Somites
BOTH –> types of cells
GAM –> sex cells (egg + sperm), haploid, produced by meiosis
SOM –> body cells, diploid, produces by mitosis
Compare + Contrast:
Gametes vs. Zygote
Both –> egg cell
GAM –> sex cell, haploid
ZYG –> fertilized egg cell, diploid
Compare + Contrast:
Diploid vs. Haploid
BOTH –> refer to number of chromosomes in a cell
DIPLOID –> contains full number of chromosomes, 46 in humans
HAPLOID –> contains half number of chromosomes, 23 in humans
Compare + Contrast:
Synapsis vs. Chiasmata
BOTH –> occur in prophase I of meiosis
SYN –> the alignment of homologous chromosomes
CHIA –> crossing over; the exchange of genetic material
Compare + Contrast:
Mitosis vs. Interphase
BOTH –> parts of cell cycle
MIT –> type of nuclear division that occurs in all body cells to produce somites which are identical to parent cell
INT –> stage when cell is NOT dividing
Compare + Contrast:
Mitosis vs. Cytokinesis
BOTH –> types of cell division
MIT –> type of nuclear division that occurs in all body cells to produce somites which are cells identical to parent cell
CYTO –> division of the cytoplasm
first organism used in genetic studies
garden pea
scientist;
studied variation/inheritance in garden peas
Scientist:
Mendel
Compare + Contrast:
Genes vs. DNA
BOTH –> genetic material
GENE –> a location on chromosome that carries information about ONE trait; made up of DNA
DNA –> makes up genes
scientist;
discovered the importance of chromosomes in heredity
Scientist:
Sutton + Boveri
scientist;
discovered that a gene is a discrete chromosome locus and is the unit of heredity
Scientist:
Morgan
organism most commonly used in genetic studies
fruit fly
a location on a chromosome
locus
genes on homologous chromosomes that carry information for the same trait (at same location)
alleles
type of inheritance;
multiple interactions between many genes
Polygenic Inheritance
Compare + Contrast:
Law of Equal Segregation
vs.
Law of Independent Assortment
BOTH –> Mendel’s laws
EQUAL SEG. –> homologous chromosomes separate to form gametes
IND. AS. –> every possible combination of genes has a chance of occuring
one allele is not completely expressed over the other; resulting in a third phenotype which is combination of the phenotypes of both alleles
incomplete dominance
Compare + Contrast:
Homozygous
vs.
Heterozygous
BOTH –> type of gene expression
HOMO –> gene alleles are exactly the same
-ex. BB, bb
HETERO –> gene alleles are different
-ex. Bb
Compare + Contrast:
Homogametic
vs.
Heterogametic
BOTH –> refer to gamete production
HOMO –> producing the same type of gamete with respect to sex chromosomes (XX)
HETERO –> having two unlike gametes (XY)
Compare + Contrast:
Dominant
vs.
Recessive
BOTH –> types of gene expression
DOM –> produces a dominant phenotype in individuals who have one copy of the dominant allele
REC –> to produce a recessive phenotype, the individual must have two copies of recessive allele
Compare + Contrast:
Genotype
vs.
Phenotype
BOTH –> refers to the coding and expression of genes
GENO –> the actual set of genes an organism carries
-ex. BB, Bb, bb
PHENO –> the visible/expressed trait
-ex. brown eyes, blue eyes, hazel eyes
Compare + Contrast:
Autosomes
vs.
Sex Chromosomes
BOTH –> types of chromosomes
AUTO –> any chromosomes that is not a sex chromosome (chromosomes 1-22)
SEX C –> a chromosomes involved with determining the sex of an organism (chromosome 23)
two genes located on the same chromosome
dihybrid
an individual that is completely normal but possesses a gene that can be passed on to offspring
carrier
chromosomes that do NOT separate during meiosis
non-disjunction
result of non-disjunction;
produces mostly normal females with menstrual irregularities + occasional learning disabilities
XXX = triplo-x
result of non-disjunction;
produces infertile female with normal intelligence
XO = Turner’s Syndrome
result of non-disjunction;
produces sterile male, sometimes slow learners, longer arms/legs, breast development
XXY = Klinefelter’s Syndrome
result of non-disjunction;
lethal, non-viable offspring, aborted
YO
must have X chromosome for survival
result of non-disjunction;
produces individual taller than average, persistent acne, learning disabilities, controversially linked with violence
XYY = Jacob Syndrome
non-disjunction of chromosome 21;
occurance is linked with age of mother
Down Syndrome
