BIO MAIN IDEAS

Surface Area to Volume Ratio

A smaller ratio signals the cell to divide to maintain efficiency in transporting materials.

Advantages of Small Cell Size

Increases efficiency of nutrient/waste exchange and communication.

DNA Organization

DNA is structured into chromatin and then chromosomes, with genes located on chromosomes.

Cell Cycle Phases

Includes interphase (G1, S, G2), mitosis (PMAT), and cytokinesis.

Cell Cycle Regulation

Controlled by checkpoints and regulatory proteins to ensure proper division.

Mitosis

Divides the nucleus into two daughter nuclei, including prophase, metaphase, anaphase, and telophase.

Apoptosis

Programmed cell death that removes damaged or unneeded cells.

Meiosis

Two rounds of division producing four haploid gametes.

DNA Nondisjunction Examples

Trisomy 21 (Down Syndrome), Turner Syndrome, and Klinefelter Syndrome.

Cellular Differentiation

Process by which unspecialized cells become specialized in structure and function.

Embryonic Stem Cells

Cells that can become any cell type.

Adult Stem Cells

Stem cells that have limited potential to differentiate into certain cell types.

Mendel’s Conclusions

Traits are inherited as genes and one allele is inherited from each parent.

Law of Segregation

Alleles separate during gamete formation.

Law of Independent Assortment

Genes separate independently in gamete formation.

Monohybrid Cross

Predicts offspring genotypes and phenotypes from one trait.

Dihybrid Cross

Predicts offspring genotypes and phenotypes from two traits.

Crossing Over

Exchange of genetic material between homologous chromosomes.

Independent Assortment

The random distribution of alleles during gamete formation.

Selective Breeding

The process of breeding for desired traits but can reduce genetic diversity.

Test Cross

A cross used to determine the genotype of an individual showing a dominant trait.

Pedigrees

Diagrams that track the inheritance of traits within a family.

DNA Structure

Double helix with anti-parallel strands and complementary base pairing (A-T, G-C).

Griffith Experiment

Demonstrated that DNA is the molecule of heredity.

DNA Replication

A semi-conservative process involving unwinding, base pairing, and joining new strands.

Transcription

The process where DNA is transcribed into mRNA in the nucleus.

mRNA Processing

Includes capping, poly-A tail addition, and splicing out introns.

Comparative RNA Types

mRNA carries code, rRNA forms ribosomes, tRNA brings amino acids.

Translation

The process of translating mRNA into a protein at the ribosome using codons and anticodons.

Genetic Code

Codons are 3-letter RNA sequences that specify amino acids.

Mutations

Changes in DNA that can occur during replication or meiosis; may affect protein function.

Examples of Mutations

Sickle cell anemia, cystic fibrosis, and color blindness.

Gene Regulation examples

Example includes the lac operon in bacteria controlling gene expression in response to lactose.