Functional unit of heredity
Gene
Multiple forms of a gene
Allele
Location on chromosome where genes are found
Locus
Complete set of genetic instructions for an organism.
RNA or DNA
Genome
Study of chemical nature of gene and how genetic information is replicated and expressed
Molecular Genetics
Frequency of certain traits from one generation to the next
Transmission Genetics
Population of traits; analyzing between populations
Population Genetics
What is the order of cell reproduction?
1) copy genetic information
2) separate copies
3) division of cell
DNA to RNA is the process of _______
transcription
RNA to protein is the process of _______
translation
How many chromosomes do humans have?
46
What protein molecule wraps around in which DNA is tightly coiled in chromatin?
Histone
DNA + protein = ?
Chromatin
Structures in a cell that group genes together and composed of chromatin & visible during mitosis
Chromosome
2 sets of genetic information
Diploid
1 set of genetic information
Haploid
Duplicated chromosome
Sister chromatid
Where do spindles attach?
Kinetochore
Where do sister chromatids attach?
Centromere
Homologous pairs do NOT align; random arrangement
Mitosis
Homologous pairs align
Meiosis
Change in sequence; favorable or unfavorable
Mutation
Importance of genes:
- agriculture
- biotechnology & medicine
- development
Is the coding system for genetic information the same in all living organisms?
Yes
Organisms with characteristics that make them useful for genetic analysis
Model genetic organisms
What are the common characteristics of model organisms?
- short generation time
- production of numerous progeny
- ability to carry out controlled genetic crosses
- availability of numerous genetic variants
- accumulated body of knowledge about their genetic systems
Unicellular, no membrane-bound organelles
Prokaryote
Unicellular and multicellular with membrane-bound organelles
Eukaryote
Neither prokaryotic or eukaryotic, not a self-sufficient living organism
Virus
Fertilized egg is an example of a _____
Zygote
Diploid cells have
Two sets of chromosomes
Constricted region of the chromosome where the kinetochores form and spindle microtubules attach
Centromere
Tip of linear chromosome; stable ends of chromosome
Telomere
Where DNA replication begins
Origins of replication
Attachment close to the middle
Submetacentric
Attached at the middle
Metacentric
Attached at the end
Telocentric
Attached near the end
Acrocentric
An extended period between cell divisions, DNA synthesis, and chromosome replication phase
Interphase
Key transition points
Phase checkpoints
Consists of G1, S, G2 and chromosome is NOT visible
Interphase
Separation of cytoplasm
Cytokinesis
What is the order of mitosis?
PMAT
Which phase is the stable, non-dividing period of variable length?
G0 phase
Which phase is the G1/S checkpoint, the growth and development of the cell?
G1 phase
Which phase is the synthesis of DNA?
S phase
Which phase prepares for division and the location of G2/M checkpoint?
G2 phase
Chromosome condense and mitotic spindle forms
Prophase
Chromosomes align on the metaphase plate; spindle-assembly checkpoint
Metaphase
Sister chromatids separate and migrate toward spindle poles
Anaphase
Chromosomes arrive at spindle poles, nuclear envelopment re-forms, and the condensed chromosomes relax.
Telophase
The production of haploid gametes
Meisosis
The fusion of haploid gametes
Fertilization
What is the consequence of meiosis?
Genetic variation
Which meiosis reduces the chromosome number by half (separation of homologous chromosome pairs)?
Meiosis I
Which meiosis has equal division (separation of sister chromatids)?
Meiosis II
Closely associated four-sister chromatids of 2 homologous chromosomes
Tetrad
Close pairing of homologous chromosomes
Synapsis
The exchange of genetic information
Crossing-over
How many cells are produced from each original cell?
4
Which of the following events takes place in meiosis II but not in meiosis I?
Separation of chromatids
In Meiosis I, what is the phase called where no DNA synthesis takes place?
Interkinesis
Where does crossing over occur?
Prophase I
All mature sperms and eggs are haploid
True
Newly formed cells from meiosis are genetically different from one another and from _____
parental cell
Does crossing over take place in mitosis?
No
The likelihood of the occurrence of a particular event
Probability
Term "and" is used for this type of probability
Multiplication Rule
Terms "either" "or" for this type of probability
Addition Rule
How are the principles of segregation and independent assortment related, and how are they different?
Genes encoding different characteristics separate and assort independently of one another when they are not located close together on the same chromosome.
Two alleles of the same gene encoding one characteristic still have to be segregated from each other during the formation of gametes
What is X?
Female
What is XY?
Male
All cells are diploid, except ______
sperm and egg (haploid)
Both sexes in the same organism
Hermaphroditism
Both male and female reproductive structures in the same organism
Monoecious
What sex determination mechanism do humans have?
Dioecious
How does the heterogametic sex differ from the homogametic sex?
Gametes of the heterogametic sex have different sex chromosomes; homogametic sex have the same sex chromosomes
Are there sex chromosomes or sex-determining genes?
Sex-determining genes
What are the environmental sex determining factors?
Position in the stack (Limpets)
Temperature in turtles
In limpets, the larvae settles on an unoccupied substrate and develop into a _____, which produces chemicals that attract other larvae.
Female
What makes limpets male?
- The larvae settled on top of female
- Additional larvae that were attracted and settled on top
In flies, what is XO?
Male
In flies, what is XXY?
Female
In humans, what is XO?
Turner's Syndrome
In humans, what is XXY?
Klinefelter Syndrome
The _____ gene on the Y chromosome determines maleness
SRY
Hemophilia is an X-linked recessive disease in humans. A woman with hemophilia mates with a man who exhibits normal blood clotting. What is the probability that their child will have hemophilia?
1/2