Mitosis/Meiosis

Mitosis

cell division in eukaryotes that results in 2 genetically identical daughter cells; increase in number of cells (growth)

Prophase

chromosomes condense; 2N

Metaphase

chromosomes line-up at middle of cell; 2N

Anaphase

chromosomes pull-apart; 2N

Telophase

nuclear envelope reforms; 2N

Cytokinesis

cell splits (cleaves); 2N

Interphase

cell growth

True/False: Growth happens equally.

False- growth rate varies

Scaling

how different structures/systems grow relative to each other

Isometry

growth of structure is proportional to growth of body; different sizes, same shaped structures

Allometry

growth of structure is not proportional to growth of body; different sizes, different shaped structures

Log Transform Data

allows for comparing the slope of straight lines instead of exponential curves

V_slope

length³ in exponential & 3 in log

A_slope

length^2 in exponential & 2 in log

L_slope

length^1 in exponential & 1 in log

Isometry slope

slope predicted by proportional growth; V = 3, A = 2, L = 1

Positive Allometry Slope

structure grows faster than overall body size; measured slope > slope of isometry

Negative Allometry

structure grows slower than overall body size; measured slope < slope of isometry

Binary Fission

cell division in bacteria & archaea that result in 2 genetically identical individual cells; replicates DNA and cytokinesis; asexual with no intentional gene change

Sexual Reproduction

genetic recombination; offspring genotypes are unique from parental genotypes; allow favorable combinations of genes to spread

Advantages of Sexual Reproduction

“Hedging bets” & Red Queen hypothesis

“Hedging Bets”

if environmental (abiotic) conditions change, having offspring with a wide range of phenotypes will ensure that at least some will surve/pass on genes

Red Queen Hypothesis

Other organisms are constantly evolving, changing biotic conditions; genetic recombination creates favorable combinations of genes to rapidly keep up

Disadvantages of Sexual Reproduction

offspring only recieve half of either parent’s genes; can be difficult to find/obtain a mate; potential mates must be genetically compatible; offspring may be less fit than either parent

Meisos

cell division in eukaryotes that results in 4 genetically unique daughter cells, with ½ of the parental genotype

End of Meiosis 1

two genetically unique 1N cells

End of Meiosis 2

four gametes genetically unique 1N cells

Independent Assortment

different arrangement of homologous chromosomes when lining up in metaphase

Crossing Over

exchanging genes when chromosomes near/on top of each other in metaphase

Genetic Recombination

gametes from two individuals fuse and combine DNA