bio chapters 13-15 & 17exam 3

• 1. Life evolves
• 2. Change occurs as a result of decent with modification with natural selection as the mechanism.

The processs in which organisms with certain inherited characteristics are more likely to survive and reprodce than individuals with other characteristics.

Enviornments!

populations: a group of individuals of the same species living in the same place at the same time.

that species are fixed and do not evolve over time.

The earth may in fact be over 6,000 years old and there are similarities between fossils and living species, and fossil forms might be ancient versions of similar living species.

• Enviornments give risse to changes in animals. Acquired characteristics could actually be interited! And organisms evolved by the process of adaption during their lifetimes and these characteristics could be inherited. i.e; the giraffes....
• This theory is now known to be incorrect...duh.

The geologist that greatly influenced Darwin. Lyell said that the earth is very old and the planet has been sculpted b by gradual geological processes that are continuing today.

• 1. The fossil record.
• 2. Biogeography.
• 3. Comparative anatomy.
• 4. Comparitive embryology.
• 5. Molecular biology.

the grand canyon...fossils reveal the appearrance of organisms in a historical sequence.!

The study of geographic distribution of species. The first field suggested to Darwin that today's organisms evolved from ancestral forms. ie; marsupials in australia!

• • Homology is the similarity in structures due to common ancestry
• • Illustrated by the remodeling of the pattern of bones forming the forelimbs of mammals

• • Comparative embryology of vertebrates supports evolutionary theory.
• Example: pharyngeal pouches appear on the side of an embryo’s throat, which:
• • Develop into gill structures in fish
• • Form parts of the ear and throat in humans

1. All species tend to produce excessive numbers Æ leads to a struggle for existence.

• 2.
• • Variation exists among individuals in a population.
• • Much of this variation is heritable.

• The smallest biological unit that can evolve

smallest scale,

polygenic results from the combination of several genes.

• • Determined by a single gene
• • Single gene traits tend to produce only a few distinct phenotypes.

p2+2pq+q2=1

the relative freguency of the dominant sllele in the population.

the frequency of the recessive allele in the population

To determine the frequencies of genotypes in a gene pool from the frequencies of alleles. This formula may be used to calculate the percentage of a human population that carries the allel for a particulaar inherited disease.

• Hardy‐Weinberg equilibrium
• • evolution can be defined as a generation‐to‐generation change in a population’s frequencies of alleles Æ
• Microevolution

• A change in the gene pool of a small population, due to chance

• • results from a drastic reduction in population size
• • usually reduces genetic variation because at least some alleles are likely to be lost from the gene
• pool.

• colony.
• • explains the relatively high frequency of certain inherited disorders among some small human
• populations.

• tends to reduce genetic differences between populations

• • Fitness is the contribution an individual makes to the gene pool of the next generation relative to
• the contributions of other individuals.
• Example: fitness of some flowering plants depends in part on competition in attracting pollinators

• 1. Directional Selection.
• 2. Disruptive selection.
• 3. Stabalizing selection.

• Selects in favor of some extreme phenotype

A distinction in appearance between males and females and is not directly associated with reproduction or survival.

• • Classifying organisms
• • Determining their evolutionary relationships

• • Naming of species
• • Classification of species
• • Identification of species

• fertile offspring
• • cannot be accurately used with Fossils or Asexual organisms

A name that is given to all living organisms that is a two part name consisting of a genus and a species.

• Species
• Genus
• • Family
• • Order
• • Class
• • Phylum
• • Kingdom
• • Domain

• • One domain of eukaryotes (Eukarya)
• • Three‐domain classification system (see Figure 14.25)

4.6 billion years ago.

• Prokaryotes lived and evolved on earth about 2 million years before any eukaryotes lived and.or evolved.
• They can cause disease but also be beneficial.

Prokaryotes lack true nuclei, they lack other membrane-bound organelles and have cell walls exterior to their plasma membranes.

• Spherical (cocci), Rod-shaped (bacilli) or spiral
• Usually prokaryotes are very small., some form true colonies like an actinomycete and some show specialization of cells and some are very large.

• 1. Phototrophs
• 2. Chemotrophs
• 3. Autotrophs
• 4. Heterotrophs

Energy source comes from light.

energy comes from enviornmental chemicals.

carbon from carbon dioxide

obtain carbon from at least one organic nutrient (glucose)

• 1. Bacteria
• 2. Archaea

Bacteria and other organisms that cause disease.

poisonous proteins secreted by bacterial cells.

chemical components of the outer membrane of certain bacteria.

Ancestral to all other eukaryotic organisms like plants, fungi and animals. and they probavblty evolved from prokaryotic ancestors.

One theory is the ENDOSYMBIOTIC THEORY, which states tthat the infolding of the plasma membrane of a prokaryotic cell actually formed the endomembrane system (the endoplasmit reticulum, etc). ENDOSYMBIOSIS produced mitochondria and chloroplasts and free-living bacteria came to reside inside of a host cell.

all the eukaryoites that are not plants, animals, or fungi.

• 1. Protozoans (first animals)
• 2. slime molds
• 3. unicellular and colonial algae
• 4. green algae

• one of the categories of protists!
• They live primarily by