Bacteria, Archaea, & Protists Bio 94 Week 4 Discussion Bacteria, Archaea, & Protists

17, 11

15. Genetic drift occurs in a population. Which of the following statements might be true? A. Genetic drift increased the population's fitness. B. The population experiences a decrease in genetic variation. C. Genetic drift decreased the population's fitness. D. Any of the statements might be true

14. Why doesn't inbreeding, by itself, cause evolution? A. It increases homozygosity. B. It violates the Hardy-Weinberg assumptions. C. It does not change the population's allele frequencies. D. It decreases the population's average fitness

What is an important consequence of gene flow in natural populations? A. Gene flow increases the mutation rate among sedentary organisms. B. Gene flow moves individuals from one habitat to another on a seasonal basis. C. Gene flow tends to separate allele frequencies among populations. D. Gene flow tends to reduce genetic differences among populations.

The two key factors responsible for allopatric speciation are A. lack of gene flow and mutation B. mutation and genetic drift. C. genetic isolation and genetic divergence. D. postzygotic isolation and morphological change

Although each of the following has a better chance of influencing gene frequencies in small populations than in large populations, which one most consistently requires a small population as a precondition for its occurrence? A. mutation B. natural selection C. genetic drift D. nonrandom mating

Why are bacteria/archaea interesting?

What was the common ancestor of all species living today, prokaryotic or eukaryotic?

Extremophiles Bacteria or archaea that live in high-salt, high-temperature, low-temperature, or high-pressure habitats. Hot area of research for understanding the tree of life, exploring the structure and function of enzymes.

Microbiome Discuss human microbiome (more bacteria cells than human cells) & metagenomics

Morphological Diversity Size Shape Motility Shows different sizes and shapes of bacteria (smallest 0.3 μm, largest 100 μm, Spirals, Swimming, Gliding)

Cell-Wall Composition

Worksheet

Metabolic Diversity Phototrophs: from sunlight Chemotrophs: from chemicals Chemoorganotrophs: organic molecules Chemolithotrophs: inorganic molecules Autotrophs: self-synthesized from simple molecules Heterotrophs: from molecules produced by other organisms

Protists Very common in oceans Euglenoid

Protists are paraphyletic

Origin of nuclear envelope, mitochondrion, and chloroplast

Worksheet

Haploid life cycle

Diploid Life Cycle

Alternation of generations Multicellular haploid and diploid forms can look identical or different