General Structure
What 3 things do multicellular organisms depend of cell division for?
Development from a fertilized cell
Growth
Repair
What is the main purpose of mitosis?
To make more cells
What is the purpose of Meiosis?
To make gametes
Which phase? Duplicated chromosomes are arranged at the metaphase plate, kinetochores of sister chromatids attach to microtubules extending from opposite poles.
Metaphase 2
What is an example of an environmental effect that is not caused by a genotype?
hydrangea flowers and their pedal color is caused by soil acidity
DNA molecules in a cell are packaged into _________.
Chromosomes
What are all stages of mitosis? What is a way to remember this?
Interphase, Prophase, Prometaphase, Metaphase, Anaphase, Telophase/cytokinesis
IPPMAT
homologs pair up and separate, resulting in two haploid daughter cells with replicated chromosomes
Meiosis 1
True or False. because of crossing over in meiosis 1, the two sister chromatids of each chromosome are no longer genetically identical
True, each chromosome will look different.
What is an example of polygenic inheritance?
What is an example of epistasis?
skin color in humans
labrador retriever coat color
What is the difference between somatic cells and gametic cells? Give an example. What is their ploidy?
Somatic cells: They are used for non-reproductive purposes. Ex: Skin, muscle... Diploid (2n)
Gametics cells: Cells used for reproductive purposes. Ex: sperm and egg. Haploid (n)
Spindle microtubule organizing center. Establishes poles.
Connection site for spindle fiber at each chromatid's centromere
Structure made of microtubules that control chromosome movement during mitosis
Centrosome
Kinectocore
Mitotic Spindle
What phase is the tighten up and pair up stage in meiosis?
What is it called when non-sister chromatids exchange DNA segments? What phase does this happen in?
Prophase 1
Crossing over; Prophase 1
What are the 3 mechanisms that contribute to genetic variation?
1. independent assortment of chromosomes
2. crossing over
3. random fertilization
True or false. Dominant alleles are not necessarily more common in populations than recessive alleles. Explain why or why not.
True.
Dominant alleles only describe how the gene is expressed.
How do you count chromosomes? Where is this structure found?
By the centromere
In between 2 sister chromatids
cancer cells may not need growth factors to grow and divide... (3 things)
1. they make their own growth factor
2. they may convey a growth factor's signal without the presence of the growth factor
3. they may simply have an abnormal cell cycle control system
Usually occurs simultaneously with Telophase 1, cleavage furrow forms.
Which phase? Each pole of the cell has a haploid set of chromosomes.
Cytokinesis
Telophase 1
at metaphase one, each pair of chromosomes assorts maternal and paternal homologs into daughter cells independently of the other pairs
independent assortment
What are Mendal's 2 Laws? What are examples of each?
Law of Segregation: each parent only passes one allele for a trait. Ex: Monohybrid cross
Law of Independent Assortment: each pair of alleles assorts independently of each other pair of alleles during gamete formation Ex: Dihybrid cross
Draw a chromosome and chromatin on the board. On the chromosome, label: sister chromatids, centromere, and duplicated chromosome
*insert picture*
Come up to the board and draw a stage of mitosis.
Make sure to state the final product of mitosis.
*insert picture*
2 genetically identical daughter cells
What is the result from Meiosis 1?
Come up to the board and draw a phase from meiosis 1.
2 genetically unique haploid daughter cells
What is the result from meiosis 2?
Draw a stage from meiosis 2.
4 genetically unique haploid daughter cells
Create a dihybrid cross. The mother has the genotype of RrYy. The father has the genotype of RrYy. Determine the phenotypic ratio.
Phenotypic ratio: 9:3:3:1