Anthropology 105 Terms to know

Anthropology

The study of humans, their cultures, history, and how they live.

Human Biology

The study of how the human body works, including its structure, functions, and how it stays healthy.

Scientific Method

A step-by-step process to answer questions or solve problems using observation and experiments.

Primary Literature

Original research written by the scientists who did the work.

Secondary Literature

Summaries or reviews of research done by others.

Prokaryote

A simple, single-celled organism with no nucleus (like bacteria).

Eukaryote

A cell with a nucleus and other organelles (plants, animals, humans).

Organelle

A tiny structure inside a cell that does a specific job (like a “mini-organ”).

Nucleus

The control center of the cell that holds DNA.

DNA

The molecule that carries genetic instructions for life.

Mitochondria

The cell’s “powerhouse” — makes energy.

Ribosomes

The structures that build proteins in a cell.

mtDNA

DNA found in mitochondria, passed down from your mother.

Somatic Cells

Body cells (skin, muscle, etc.) — not sperm or eggs.

Gametes

Reproductive cells — sperm and eggs.

Nucleotides

The building blocks of DNA, made of sugar, phosphate, and a base.

Adenine

A DNA base that pairs with Thymine (A–T).

Thymine

A DNA base that pairs with Adenine (T–A).

Guanine

A DNA base that pairs with Cytosine (G–C).

Cytosine

A DNA base that pairs with Guanine (C–G).

General Process of DNA Replication

DNA makes a copy of itself before a cell divides.

Gene

A section of DNA that gives instructions for a trait.

Diploid / Haploid

Diploid = two sets of chromosomes (body cells).
Haploid = one set of chromosomes (gametes).

Chromatin

Loose, uncoiled form of DNA in the nucleus.

Chromosome

Tightly coiled DNA that appears during cell division.

Homologous

Matching pairs of chromosomes (one from mom, one from dad).

Main message of article “The Forgotten Father of Epigenetics”

E. E. Just’s work shows that diversity brings new ideas to science. His overlooked theory hinted at modern epigenetics and proves why including different voices leads to discovery.

Homologous pair

Two chromosomes (one from each parent) that are the same size and contain the same types of genes.

Mitosis

Cell division that makes two identical body cells (for growth and repair).

RNA

A single-stranded molecule that carries genetic information or helps build proteins.

mRNA

A type of RNA that copies instructions from DNA and brings them to the ribosome.

Transcription

The process of making an mRNA copy from DNA.

Translation

The process where ribosomes use mRNA to build a protein.

tRNA

A type of RNA that carries amino acids to the ribosome during translation.

Uracil vs. Thymine

Uracil (U) is in RNA, while Thymine (T) is in DNA.

Ribosome

The cell’s protein-making machine.

Meiosis

Cell division that makes four unique sex cells (gametes) with half the number of chromosomes.

Somatic cell

Any body cell that is not a sperm or egg.

Gamete

A sex cell (sperm or egg) used for reproduction.

Haploid

A cell with half the normal number of chromosomes (like a gamete).

Diploid

A cell with the full set of chromosomes (like a body cell).

Mutation

A change in the DNA sequence.

Somatic vs. Germ-line Mutation –

• Somatic: Happens in body cells, not passed to offspring.
• Germ-line: Happens in sperm/egg cells, can be passed to offspring.

Random Assortment

The random way chromosomes separate into gametes during meiosis, creating variety.

Recombination (Crossing Over)

When paired chromosomes exchange pieces during meiosis, mixing up genes.

Autosome

Any chromosome that is not a sex chromosome (pairs 1–22 in humans).

Sex Chromosome

The X or Y chromosome that determines biological sex.

Allele

A version of a gene (for example, blue-eye allele or brown-eye allele).

Locus

The physical spot where a gene is located on a chromosome.

Complex Trait vs. Simple Trait

• Simple Trait: Controlled by one gene (e.g., cystic fibrosis).
• Complex Trait: Controlled by many genes and often affected by environment (e.g., height).

Genotype

The genetic makeup of an organism (the alleles it has).

Dominance

When one allele masks the effect of another (shown as the trait).

Recessive

An allele that is hidden when a dominant allele is present; only shows if two copies are present.

Homozygous

Having two of the same allele (AA or aa).

Heterozygous

Having two different alleles (Aa).

Punnett Square

A tool used to predict possible offspring genotypes.

ABO Blood Groups

The classification of blood type as A, B, AB, or O, based on antigens on red blood cells.

Codominance

When two alleles are both fully expressed (like type AB blood showing both A and B).

Human Genome Project

A research project that mapped all human genes.

Complex Trait

A trait influenced by many genes and environmental factors.

Polygenic Inheritance

When multiple genes work together to produce one trait (like skin color or height).

Height (and why it’s a complex trait)

Height is influenced by many genes and environmental factors (nutrition, health), making it polygenic and complex.

Heritability

The proportion of variation in a trait that can be explained by genetics (in a specific population).

Epigenetics

Changes in gene activity that don’t change the DNA sequence but can be passed on.

DNA Methylation

Adding a chemical tag (methyl group) to DNA to turn genes “off.”

Histone Modification

Changing the proteins DNA wraps around, making genes more or less accessible.

microRNA

Small RNA molecules that block or slow down protein production.

Intergenerational Epigenetic Effects

When epigenetic changes (like methylation) are passed from parents to offspring.

Species

A group of organisms that can breed with each other and produce fertile offspring.

Taxon

A group used in classifying organisms (like species, genus, family).

Lamarck

Early scientist who suggested that traits acquired during life could be passed to offspring.

Competition for Resources

When organisms fight for food, space, mates, or other necessities.

Levels of Regulation of Gene Expression

Control of genes at different stages: DNA (epigenetic), RNA (transcription/processing), or protein level.

Epigenetic Marks

Chemical tags (like methyl groups) that control whether a gene is turned on or off.

Hox Genes

Genes that control body plan layout (like where arms, legs, or wings grow).

Plasticity

The ability of an organism to change in response to the environment.

Developmental Plasticity

When the environment affects how an organism develops (e.g., nutrition influencing growth).

Binomial Nomenclature

The two-part scientific naming system for species (Genus + species, like Homo sapiens).

Descent from Common Ancestor

The idea that all living things share a common origin.

Extinction

When a species completely dies out.

Adaptation

A trait that improves an organism’s ability to survive and reproduce.

Darwin

Scientist who developed the theory of natural selection as the main driver of evolution.

Natural Selection

The process where organisms with helpful traits survive and reproduce more, passing those traits on.

Evolution

Change in the genetic makeup of a population over time.

Directional Selection

When natural selection favors one extreme of a trait (e.g., faster cheetahs).

Positive Selection

When a helpful mutation is favored and spreads through a population.

Negative (Purifying) Selection

When harmful mutations are removed from a population.

Balancing Selection

When multiple versions of a gene are kept in a population because they are beneficial in different situations (e.g., sickle cell trait vs. malaria).

Genetic Drift

Random changes in gene frequencies, especially in small populations.

Founder Effect

When a small group starts a new population, leading to reduced genetic diversity.

Gene Flow

The movement of genes between populations (through migration or interbreeding).

Selectionist Hypothesis

The idea that most genetic differences are shaped by natural selection.

Neutral Theory

The idea that most genetic changes are neutral (not helpful or harmful) and spread by chance.

Extended Evolutionary Synthesis

A modern version of evolutionary theory that includes epigenetics, plasticity, and other new ideas beyond natural selection and genetics.

Modern Synthesis

The combination of Darwin’s natural selection and Mendelian genetics into one theory of evolution.

Developmental Bias

The idea that some traits are more likely to evolve than others because of how development works.

Niche Construction

When organisms change their environment in ways that affect their own evolution (e.g., beavers building dams).

Extra-genetic Inheritance

When traits are passed to offspring through non-DNA ways (like epigenetics, culture, or behavior).