Bio 106 Exam 1

hanjo hellmann - wsu

Who developed binomial nomenclature?

Carolus Linnaeus

Carolus Linneaus

• Swedish Botanist

• Father of Taxonomy

• Focused on naming/classifying all forms of life

Systemma Naturae

A book by Linnaeus, named a large number of species and developed the binomial system

Taxonomy

The ordered division of organisms into categories based on a set of characteristics used to assess similarities and differences.

Plato & Aristotle believed…

• The world is perfect but perceive an imperfect representation

• All life forms can be arranged on a ladder of increasing complexity

  • Evolution is not possible

Scala Naturae

Life forms have a permanent spot on a graded scale of complexity, perfection, and value

Natural Theology

Classify species to reveal the steps of the scala naturae

T or F: The grouping of similar species implies an evolutionary relationship.

False

Georges Cuvier

• French anatomist

• Noted each stratum was characterized by a unique group of fossil species

• Deeper stratum contained flora and fauna more dissimilar from modern life forms

• Recognized extinction, NOT evolution

Catastrophism

Cuvier’s anti-evolution explanation. States local species are destroyed by a catastrophic event and their remains are fossilized in a strata. The area would later be repopulated by species coming from an unaffected area.

Jan Baptiste Lamarck

• French Botanist

• Compared living species with fossils and found a chronological series of older to younger fossils leading to a living species

• Believed in Scala NAturae but felt organisms could change their position on the ladder of life as they moved toward perfection

Who published the first theory of evolution?

Jan Baptiste Lamarck

What is Lamarck remembered for?

• Use/Disuse: Parts of the body that are used become stronger while unused parts deteriorate

• Inheritance of Acquired Characteristics: Acquired/”Trained” traits cannot be inherited

James Hutton

• Scottist geologist

• Father of modern Geology

Define gradualism

Variation in land forms can be explained by gradual change

Charles Lyell

• Scottist geologist

• Proposed uniformitarianism

• Also believed in slow continuous action rather than sudden events

Define uniformitarianism.

Geological processes have not changed. The rates at which these forces operate have always been the same.

Define geological gradualism.

Dramatic changes in the earth’s geological features is due to the cumulative product of slow but continuous processes.

Define Darwin’s 2 main ideas in his book

1. The numerous species of organisms are descendants of ancestral species that differ from modern species

2. Natural selection is a cause of adaptive evolution

What are the two basic patterns of evolutionary change?

Anagenesis: Speciation without splitting

Cladogenesis: Speciation with splitting

Define population genetics

The study of how populations change genetically over time

Define a population

A localized group of individuals that are capable of interbreeding and producing fertile offspring.

What is heritable variation based on?

Mutation & Sexual recombination

What are mutations?

Changes in the nucleotide sequence of DNA that cause new genes and alleles to arise

Define point mutation.

A change in one base in a gene.

Define gene pool.

The total aggregate of genes in a population at any one time.

What 3 factors alter allele frequencies and bring about most evolutionary change?

1. Natural selection

2. Genetic drift

3. Gene flow

Define genetic drift.

How allele frequencies can fluctuate unpredictably from one generation to the next.

• Tends to reduce genetic variation

Define founder effect.

When a few individuals become isolated from a larger population, affecting allele frequencies.

Define bottleneck effect.

A sudden change in the environment that may drastically reduce the size of a population.

What does differential success in reproduction do?

It results in certain alleles being passed to the next generation in greater proportions.

Define fitness

The contribution an individual makes to the gene pool of the next generation, relative to the contributions of other individuals.

Define directional selection.

Favors individuals at one end of the phenotypic range.

Define disruptive selection.

Favors individuals at both extremes of the phenotypic range.

Define stabilizing selection.

Favors intermediate variants and acts against extreme phenotypes.

Define INTERsexual and INTRAsexual selection.

Intersexual: When individuals of one sex are choosy in selecting their mates, like through appearance.

Intrasexual: Direct competition among individuals of one sex for mates of the opposite sex, like fighting.

Define the biological species concept.

Defines a species as a population or group of populations whose members have the potential to interbreed in nature and to produce viable, fertile offspring but are unable to produce viable fertile offspring with members of other populations.

Define reproductive isolation

The existence of biological factors that impede members of 2 species from producing viable, fertile hybrids

How do PREZYGOTIC barriers act as reproductive isolation?

Impede mating between species or hinder the fertilization of ova if members of different species attempt to mate.

How do POSTZYGOTIC barriers act as reproductive isolation?

Prevent the hybrid zygote from developing into a viable, fertile adult?

Define Habitat Isolation

Two species that occupy different habitats within the same area may encounter each other rarely, it at all, even though they are not isolated by obvious physical barriers such as mountain ranges.

Define temporal isolation.

Species that breed during different times of the day/seasons/years cannot mix their gametes.

Define behavioral isolation

Courtship rituals that attract mates and other behaviors unique to a species are effective reproductive barriers, even between closely related species.

Define mechanical isolation

Morphological differences prevent successful mating.

Define gametic isolation.

Sperm of one species may not be able to fertilize the eggs of another species.

Define hybrid viability.

The genes of different parent species may interact and impair the hybrids development or their fertlity

Define hybrid breakdown

Some first-gen hybrids are viable and fertile, but when they mate, offspring of the next generation are feeble or sterile.

What can the biological species not be applied to?

• Asexual organisms

• Fossils

• Organisms about which little is known regarding their reproduction

Define morphological species concept.

Characterizes a species in terms of its body shape, size, and other structural features

Define paleontological species concept

Focuses on morphologically discrete species known only from the fossil record

Define ecological species concept

Views a species in terms of it’s ecological niche.

Define phylogenetic species concept

Defines a species as a set of organisms with a unique genetic history.

Define allopatric speciation

A population forms a new species while geographically isolated from its parent population

Define sympatric speciation

The emergence of a reproductive barrier isolates a subset of a population without geographic separation from the parent species.

What happens in a hybrid zone?

Allopatric populations come into contact with each other again and members of the different species can meet and mate, potentially producing offspring of mixed ancestry.

List Linnaeus’ hierarchical classification from most specific to most broad. (hint: 8 terms)

1. Species

2. Genus

3. Family

4. Order

5. Class

6. Phylum

7. Kingdom

8. Domain

Define phylogenetic trees.

A tree that depicts evolutionary relationships, showing patterns of divergence of species.

Define Homology.

Characteristics are shared by a set a species and are present in their common ancestor.

Define convergent evolution.

Similar environmental pressures and natural selection produce similar (analogous) adaptations in organisms from different evolutionary lineages.

Define homoplasy.

Analogous structures or molecular sequences that evolved independently.

Define monophyletic group.

A clade signifying that it consists of the ancestor species and all its descendents.

What are the three basic plant organs?

1. Roots

2. Stems

3. Leaves

What is a root?

An organ that anchors the vascular plant, absorbs minerals and water, and stores organic nutrients

Where does absorption occur in roots?

Near the root tips, where root hairs increase root surface area

Prop roots

An aerial root that grows from a plants stem or branch and provides support.

Strangling roots

A root that grows in a circular or spiral pattern, strangling the trunk,

Buttress roots

Large, wide roots that grow on all sides of a tree’s base, providing support and preventing the tree from falling over.

Pneumatophore Roots

Roots that grow vertically upwards from a plant’s underground root system

What does a stem consist of?

Nodes (the point at which leaves are attached) and internodes (the stem segments between nodes)

Define Bulbs — stems

Vertical, underground shoots that consist of mostly the enlarged bases of leaves that store food.

Stolons (stems)

Horizontal stems that grow along the surface.

Tubers (stems)

Enlargest ends of rhizomes specialized for storing food.

What is the leaf?

The main photosynthetic organ of most vascular plants.

What do leaves consist of?

A flattened blade, a stalk, and the petiole (joins the leaf to a node of the stem)

Tendrils (leaves)

Provide support to the plant as it climbs up a structure

Spines (leaves)

Protect the plant from herbivores, radiate heat from the stem during the day, and collect and drip condensed water vapor during the cooler night.

Bracts (leaves)

Protect young flower buds, attract pollinators, or help protect developing fruits

Three types of plant organ tissue systems

Dermal, vascular, and ground tissues

What are the two parts to the dermal tissue system?

Epidermis and periderm

What does the vascular tissue system do?

Carriers out long-distance transport of materials between roots and shoots

What are the two tissue types in the vascular tissue system?

Xylem and Phloem

What does Xylem do?

Conveys water and dissolved minerals upward from roots into the shoots

What does phloem do?

Transports organic nutrients from where they are made to where they are needed

What are the cells in ground tissue specialized for?

Storage, photosynthesis, and support

Where are apical meristems located?

The tip of roots and in the buds of shoots

What do apical meristems do?

Elongate shoots and roots through primary growth and establish first tissues

What do lateral meristems do?

Add thickness to woody plants through secondary growth

What does cell elongation involve?

Uptake of water and weakening of the cell wall

Primary growth of roots produces…

The epidermis, ground tissue, and vascular tissue

A shoot apical meristem…

a dome shaped mass of dividing cells at the tip of the terminal bud. It gives rise to a repetition of internodes and leaf-bearing nodes

Vascular cambium

A cylinder of meristematic cells one cell thick. Develops from parenchyma cells

Cork Cambium

Gives rise to the secondary plant body’s protective covering (periderm)

Periderm

Consists of the cork cambium plus the layers of cork cells it produces

Bark

Consists of all the tissues external to the vascular cambium, including secondary phloem and periderm

When the tree ages, what happens to the heartwood and sapwood?

The heartwood no longer transports water and minerals, but the sapwood does