Biology Essentials Outcomes

Evolution by natural selection

The process by which favorable mutations in a population increase in frequency over time, leading to changes in the population's characteristics.

Recombination

The process of exchanging genetic material between homologous chromosomes during meiosis, resulting in new combinations of alleles.

Descent with modification

The idea that all organisms share a common ancestor and have evolved over time, leading to similarities in their anatomical structures and embryonic development.

Scientific theory

A testable explanation of natural phenomena that is supported by evidence and can be falsified.

DNA replication

The process by which DNA is copied during the cell cycle, resulting in two identical copies of the DNA molecule.

Mitosis

The process of cell division in which a single cell divides into two identical daughter cells.

Meiosis

The process of cell division in which a diploid cell divides into four genetically different haploid daughter cells.

Homologous chromosomes

Chromosome pairs that carry the same genes in the same locations, but may have different alleles.

Recombination

The process by which new combinations of alleles are created during meiosis through the exchange of genetic material between homologous chromosomes.

Selection

The process by which certain traits or alleles become more or less common in a population over time due to their effects on survival and reproduction.

Genetic equilibrium

The state in which allele frequencies in a population remain constant over generations, indicating no evolution is occurring.

Dominance

The relationship between alleles where one allele masks the expression of another allele in the heterozygous condition.

Evolution

The change in allele frequencies in a population over time, resulting in the development of new species and the adaptation of existing species to their environment.

Kin selection

The theory that individuals are more likely to help their relatives, as it increases their inclusive fitness and the chances of their alleles being passed on.

Phylogenetic tree

A diagram that represents the evolutionary relationships between different species or groups of organisms.

Monophyletic group

A group of organisms that includes a common ancestor and all of its descendants.

Parsimony

The principle that the simplest explanation or phylogenetic tree is usually the most likely to be correct.

Homology

Similarities between organisms that are due to shared ancestry.

Homoplasy

Similarities between organisms that are due to convergent or divergent evolution, rather than shared ancestry.

Species concept

A way of defining and categorizing species based on different criteria, such as morphology, reproductive compatibility, or evolutionary history.

Proximate explanation

The physical and biochemical mechanisms underlying a trait.

Ultimate explanation

The role of natural selection, arms races, history, and chance in creating or continuing a trait.

Costs of large brains

Large brains cost 2% of mass and 20% of energy.

Possible advantages of large brains

The utility hypothesis suggests that large brains provide survival-related skills favored by natural selection, while the mating mind hypothesis suggests that large brains provide mating-related skills favored by sexual selection.

Deep Learning

Making connections, understanding, and applying knowledge, excluding memorization.

Serial Dilutions

Calculation of CFU/mL using dilution factor and volume of culture plate. Dilution factor is calculated by dividing final volume by sample volume and multiplying by the denominator of serial dilution fractions.

Role of cyclin in the cell cycle

Cyclin regulates the rate of cell division and is important in cell cycle checkpoints.

Microscope calibration

Formula for measuring objects using stage divisions and ocular divisions. Calculation of magnification using ocular lens and objective lens.

Chi squared statistical analysis

Null Hypothesis states no effect/correlation/will be no change. Alternate Hypothesis states there is an effect/correlation/will be a change. Chi squared analysis determines if data is significant enough to support the alternate hypothesis. Calculation:x^2 = sum of ((O-E)^2/E). Critical value is compared to chi-square value for statistical significance.

Primary vs secondary scientific articles

Primary articles contain original data and ideas from scientific investigations reported by scientists. Secondary articles review and analyze primary sources in more depth.

FST Population Genetics

FST = 1 - (average heterozygosity expected within populations / heterozygosity expected across total population). HS = (2p1q1 + 2p2q2)/2. HT = 2pTqT. Interpretation of FST values:FST = 0:no disturbance, FST > 0.25:significant disturbance, FST = 1:complete separation of populations.

Allozyme Electrophoresis for genetic variability calculation

Takes advantage of allelic variants of enzymes called allozymes. Genotype at a gene locus coding for an enzyme can be inferred from the number and position of spots observed on gels. Genetic variation in a population is the average frequency of heterozygous individuals per locus.

Creating phylogenetic trees using DNA sequencing

Phylogenies can be estimated by looking at differences in DNA sequence. The species with the most differences is the out-group. If no differences, it is the same species and should be drawn on the same vertical line. Length of horizontal lines may indicate the