GE1341 Life and Health - Lecture 1 Flashcards

Flashcards reviewing key concepts from GE1341 Life and Health Lecture 1, covering characteristics of life, biodiversity, classification, evolutionary evidence, taxonomic hierarchy, and Darwinian medicine.

What is the assessment weight distribution for the GE1341 Life and Health course?

Quizzes account for $70\%$ ($35\%$ each), Group discussion / poster presentation accounts for $20\%$, and In-class / online discussion accounts for $10\%$.

What is the primary purpose of the Drake equation formulated in 1961?

To estimate the number of active, communicative extraterrestrial civilizations in our galaxy.

How many mass extinctions have occurred in the last $530\,\text{million}$ years, and what proportion of species was eliminated in each?

There have been $5$ mass extinctions in the last $530\,\text{million}$ years, each eliminating $50\%$ or more of species.

Which historical mass extinction was the largest, and which was the most recent?

The largest was the Permian-Triassic mass extinction, and the most recent occurred during the Cretaceous period, which ended the dinosaurs.

What are the three domains of life in biological classification?

1. Domain Bacteria
2. Domain Archaea
3. Domain Eukarya

Which four kingdoms are categorized under Domain Eukarya?

Kingdom Protista, Kingdom Animalia, Kingdom Fungi, and Kingdom Plantae.

What characteristics of life are represented by the mnemonic acronym MRS C GREN?

Movement, Respiration, Sensitivity, Control (homeostasis), Growth, Reproduction, Excretion, and Nutrition.

How are organisms classified within Kingdom Animalia regarding cell number, cell type, feeding type, named species, and estimated species?

Animals are multicellular, eukaryotic, heterotrophic organisms with $1,367,555$ named species and an estimated $9,812,000$ species.

How is a species defined in biological classification?

A group composed of one or more populations of organisms with similar physical and functional characteristics that can interbreed under natural conditions to produce fertile offspring.

What are the standard formatting rules for binomial nomenclature?

The Genus name is listed first with a capital first letter and italicized, followed by the species name in all lowercase letters and italicized (e.g., Homo sapiens).

What are the eleven levels of biological organization listed in order of increasing complexity?

Atom, Molecule, Cell, Tissue, Organ, Organ system, Organism, Population, Community, Ecosystem, Biosphere.

What are homologous structures, and what is a prime example found in vertebrates?

Homologous structures are body structures that share a common evolutionary origin, such as the vertebrate forelimb (found in humans, dogs, whales, and birds).

What are analogous structures, and how do they differ from homologous structures?

Analogous structures share a similar function but have distinct evolutionary origins (e.g., bird wings vs. insect wings), whereas homologous structures share a common origin.

What is a vestigial structure, and what is an example present in the human body?

A vestigial structure is a body structure that no longer retains its original function but is homologous to functional structures in other organisms, such as the human coccyx.

Which four anatomical features demonstrate striking similarities among different vertebrate embryos during early development?

1. Gill or pharyngeal slits
2. Post-anal tail
3. Notochord
4. Body segmentation (somites)

What is adaptive radiation in evolutionary biology?

Short bursts of evolutionary activity where many new species rapidly develop from a common ancestor.

What shared physical traits define primates, and how long ago did their common ancestor live?

Primates possess hands with five digits, fairly flat fingernails and toenails, and forward-facing eyes; their common ancestor lived approximately $60\,\text{million}$ years ago.

What are the four primary defining features of modern humans?

1. Bipedalism (upright stance and walking on two legs)
2. Opposable thumbs
3. Large brain relative to body size
4. Capacity for spoken and written language

What is the complete taxonomic hierarchy for modern humans (Homo sapiens)?

Domain: Eukarya, Kingdom: Animalia, Phylum: Chordata, Class: Mammalia, Order: Primata (or Primates), Family: Hominidae, Genus: Homo, Species: sapiens.

When did Order Primata, Family Hominidae, and Genus Homo first appear according to the human taxonomic timeline?

Order Primata appeared $60\,\text{mya}$, Family Hominidae appeared $5\,\text{mya}$, and Genus Homo appeared $1.8\,\text{mya}$.

What are the three key elements that define evolution?

1. Evolution involves descent over time (slow population changes over generations).
2. Evolution involves genetic modification (DNA changes).
3. Evolution is unpredictable and natural.

How did the reproduction rate ($R$ value) of the COVID-19 Delta variant compare to the original strain?

The original strain had an estimated reproduction rate of $R = 2.5$, while the Delta variant had an upper-bound estimate of $R = 8$.

How did the World Health Organization (WHO) define health in 1948?

"A state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity."

According to the Social Determinants of Health (#SDOH) model for Canadians, what four main factors determine health outcomes and their respective percentages?

1. Your Life (50%)
2. Your Health Care (25%)
3. Your Biology (15%)
4. Your Environment (10%)

What is Darwinian (Evolutionary) Medicine?

The enterprise of using the basic science of evolutionary biology in the service of medicine and public health.

What six evolutionary reasons explain why diseases exist according to Darwinian Medicine?

1. Mismatch: body in a novel environment
2. Competition with fast evolving organisms
3. Every trait is a trade-off
4. Constraints on natural selection
5. Organisms shaped for reproduction/survival, not health
6. Defenses and suffering