Biology Q3 Flashcards
Chromatin
A complex of DNA and protein found within all animal cells
Somatic Cell / Diploid Cell
A cell not involved in sexual reproduction and containing haploid pairs of chromosomes
Gamete / Haploid cell
A cell used for sexual reproduction and containing only one set of chromosomes
Sperm and eggs
Chromasome
A long DNA structure containing genetic information
Chromatid
One half of a duplicated chromosome, still attached to another chromatid
Centromere
The point of connection of two chromosomes
Mitosis
The process by which somatic cells reproduce
Making a genetically identical cell
The five phases of mitosis (PMAT)
Prophase (+Prometaphase)
Metaphase
Anaphase
Telophase
Interphase
The time period when mitosis/meiosis is not occurring
Replication of chromatids also occurs during this time
Prophase (Mitosis)
The first phase of mitosis
Centromeres condense into visible chromosomes (which have already been replicated into chromatids), spindle fibers begin to form
Prometaphase
The 1.5 phase of mitosis
The nuclear envelope dissolves, proteins form around the centromere (Sometimes considered part of prophase)
Metaphase
The 2nd phase of mitosis
The chromosomes line up in the center of the cell
Anaphase
The 3rd phase of mitosis
Spindle fibers pull chromatids apart towards separate poles of the cells
Telophase
4th and final phase of mitosis
The cell itself splits in two
How long does mitosis usually take?
48 hours
Binary Fission
The process of cellular reproduction in prokaryotes
Much faster than mitosis
Homologous Pairs
Corresponding pairs of chromosomes
Have the same genes in the same order, but may have different alleles
How many chromosomes do human somatic cells contain? How may pairs?
46 chromosomes
23 pairs
Locus
The location of a specific gene in the chromosome
What are the 3 means used to create increased genetic diversity during sexual reproduction?
Crossing Over
Random Assortment of Chromosomes
Random Fertilization
Crossing Over
The processes by which homologous pairs of chromosomes swap some alleles during prophase 1 of meiosis
Random Assortment of Chromosomes
The randomization of which of a homologous pair of chromosomes goes to which gamete during meiosis
Random Fertilization
The randomization of which sperm will fertilize the egg during fertilization (i.e. the randomization of which setup chromosomes actually fertilizes the egg)
Trait Vs. Character
Trait is a characteristic that is determined by DNA (e.g. hair color)
Character is a possible variant of the trait (e.g. black or blond hair)
Phenotype
Physical manifestation of the genotype (e.g. a character)
Genotype / aAllele
The DNA makeup for a specific trait
True Breeding
Breeding for a specific trait
Law of separation
Alleles separate during meiosis
What two the properties of genetics discovered by Gregor Mendel?
- Both parents pass their DNA on to their offspring
- DNA contains dominant and recessive traits
True Breeding
Two parents will always produce a certain phenotype in their offspring
Test-Cross
Breeding an organism with an unknown genotype with an organism with a known homozygous recessive genotype
Determines genotype of subject organism by assessing the phenotypes of offspring
Monohybrid
An organism that is heterozygous in 1 genotype
Dihybrid
An organism that is heterozygous in 2 genotypes
Monohybrid Cross
Dihybrid Cross
Breeding monohybrid organisms together
Breeding dihybrid organisms together
Complete Dominance
Phenotype of heterozygous genotype is the same as the phenotype of homozygous genotype
Incomplete Dominance
Phenotype of heterozygous gene is a intermideate of dominant and recessive phenotypes
Codominacne
Phenotype of heterozygous gene includes both dominant and recessive characteristics
What are the benefits and drawbacks of sexual reproduction over asexual reproduction
+ Increased genetic diversity
- Requires a second organism
- Requires more energy
