BIO 182 Exam 1

Halophiles

"salt-loving" archaea that live in environments that have very high salt concentrations

Sex Pilus

(Pili) are longer than fimbriae and allow prokaryotes to exchange DNA

Darwin's four observations about nature

1. Members of a population often vary in their inherited traits 2. All species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce 3. Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than other individuals 4. This unequal ability of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations

Genetic Drift

A change in the allele frequency of a population as a result of chance events rather than natural selection.

Arbuscular Mycorrhizae

A distinct type of endomycorrhiza formed by glomeromycete fungi, in which the tips of the fungal hyphae that invade the plant roots branch into tiny treelike structures called arbuscles.

Arbuscular

A distinct type of endomycorrhizae formed by glomermycetes

Stramenopiles

A group that has both hairy and smooth flagella.

Dikaryon

A hypha with two haploid nuclei

Fungi

A kingdom made up of nongreen, eukaryotic organisms that have no means of movement, reproduce by using spores, and get food by breaking down substances in their surroundings and absorbing the nutrients

Population

A local group of organisms belonging to the same species and capable of interbreeding According to evolutionary theory, the smallest entity that can evolve is *evolve over time

Glomeromycetes

A member of the fungal phylum Glomeromycota, characterized by a distinct branching form of mycorrhizae called arbuscular mycorrhizae

Ciliate

A paramecium is a good example of a ______and exhibits many hair-like cilia on its surface. Conjugation and reproduction are separate parts of their life-cycle.

Catastrophism

A principle that states that geologic change occurs suddenly

Natural Selection

A process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than other individuals because of those traits.

Mycorrhizae

A relationship between fungi and roots of plants

Commensalism

A relationship between two organisms in which one organism benefits and the other is unaffected

Parasitism

A relationship between two organisms of different species where one benefits and the other is harmed

Mutualism

A relationship between two species in which both species benefit

Chlamydia

A sexually transmitted disease, the most common in developed countries, caused by the bacterium Chlamydia trachomatis. Often producing no symptoms, it can cause infertility, chronic pain, or a tubal pregnancy if left untreated.

Plasmid

A small ring of DNA that carries accessory genes separate from those of the bacterial chromosome

Cellulose

A substance (made of sugars) that is common in the cell walls of many organisms

Lichens

A symbiotic association of million of photosynthetic microorganisms held in a mass of fungal hyphae

Endospores

A thick-walled protective spore that forms inside a bacterial cell and resists harsh conditions

Endomycorrhiza

A type of mycorrhizae that, unlike ectomycorrhizae, do not have a dense mantle ensheathing the root. Instead, microscopic fungal hyphae extend from the root into the soil.

Pilobolus

A zygomycete that uses a light spot to aim its sporangia toward a good food source

Fungal Hyphae

Absorb minerals from the soil and exchange with sugars from the plant (mutualism)

Saprobes

Absorb nutrients from dead matter

Parasites

Absorb nutrients from living hosts

Golden Algae

Algal group having yellow and brown carotenoids and are photosynthetic.

Euglenid

An autotrophic/photosynthetic organism that has a light detector and chloroplast, as well as two flagella

Septa

An incomplete cross-wall dividing hyphae into separate cells

Mycellium

An interwoven mass of fungal hyphae that surrounds the material on which the fungus feeds

Apicomplexan

An organism that is a parasite that causes malaria and has a complex of organelles at one end used for attacking prey belongs in the _________ group

Facultative Anaerobes

An organism that makes ATP by aerobic respiration if oxygen is present but that switches to fermentation under anaerobic conditions.

Chemoheterotrophs

An organism that must consume organic molecules for both energy and carbon.

Photoheterotrophs

An organism that uses light to generate ATP but that must obtain carbon in organic form.

Facultative

An organism that will use oxygen (aerobic metabolism) if it is available, and that can ferment (anaerobic metabolism) if it is not.

Dinoflagellate

An organism with two flagella arranged in perpendicular (90 degrees to each other) grooves and emits a bioluminescent glow when disturbed.

Thermophiles

Archaea that thrive in very hot environments, such as volcanic springs.

Homologous Structures

Are anatomical resemblances that represent variations or structural theme present in a common ancestor

Green Algae

Are photosynthetic and contain many chloroplasts

Red Algae

Are photosynthetic and contain phycoerythrin

The Three Great Clades

Bacteria, Archaea, Eukaryotes

Postzygotic

Barriers that prevent the hybrid zygote from becoming a fertile adult.

Ascomycetes

Bear their spores in a sac

Basidiomycetes

Bear their spores on a pedestal

Linnaeus

Binomial nomenclature

Artificial Selection

Breeding organisms with specific traits in order to produce offspring with identical traits.

Artificial selection

Breeding organisms with specific traits in order to produce offspring with identical traits.

Coenocytic cells

Cells that lack septa

Microevolution

Change in allele frequencies in a population over generations.

Quantitative

Characters (such as height) are those that vary along a continuum within a population.

Phylogeny

Classification of organisms

Chitin

Component of fungi cell walls

Gene Pool

Consists of all the alleles for all loci in a population

Biological species concept

Definition of a species as a population or group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring, but are not able to produce viable, fertile offspring with members of other populations.

Discrete

Distinct, separate

Anaerobes

Do not require oxygen to live

Macroevolution

Evolutionary change above the species level.

Directional Selection

Form of natural selection in which the entire curve moves; occurs when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve

Karyogamy

Fusion of the nuclei contributed by the two fungi individuals

Speciation

Genetic changes over time

Amoebozoans

Have a lobe-shaped pseudopodia

Euglenozoans

Have flagella with internal spiral or crystalline rods

Alveolates

Have membrane-bound sacs beneath the plasma membrane

Exoenzymes

Hydrolytic enzymes released by fungi into their surroundings

Haustoria

In parasitic fungi, a nutrient-absorbing hyphal tip that penetrates the tissues of the host but remains outside the host cell membranes.

Mutation

Is a random change in nucleotide sequence of DNA

Facultative fungi

May be grown without the host

Gene Flow

Movement of alleles into or out of a population due to the migration of individuals to or from the population

Gene flow

Movement of alleles into or out of a population due to the migration of individuals to or from the population

Eukaryotic

Multicellular organism

Obligate Fungi

Must have host

Stabilizing

Natural selection that favors intermediate variants by acting against extreme phenotypes

Stabilizing Selection

Natural selection that favors intermediate variants by acting against extreme phenotypes

Gradualism

Occurrence over a period of time

Diatoms

Organisms having a silica wall and, during mitosis, the organism splits and each half generates a new half to fit.

Chemoautotrophs

Organisms that use hydrogen sulfide or other chemicals as energy source instead of light.

Photoautotrophs

Organisms that use light as a source of energy to synthesize organic substances.

Heredity

Passing of traits from parents to offspring

Cyanobacteria

Photosynthetic, oxygen-producing bacteria (formerly known as blue-green algae).

Zygomycetes

Plasmogamy of theses fungi produces a sturdy structure called zygosporangium

Nitrogen Fixation

Process of converting nitrogen gas into nitrogen compounds that plants can absorb and use

The theory of gradualism

Profound geological changes took place through the cumulative effect of slow but continuous processes identical to those currently operating

Obligate Anaerobes

Prokaryotes that cannot live in the presence of oxygen

Diplomonads

Protists that have two equal-sized nuclei and multiple flagella

Coenocytic

Referring to a multinucleated condition resulting from the repeated division of nuclei without cytoplasmic division.

Creationism

Religious viewpoint

Prezygotic

Reproductive barrier that prevents a species from mating

Prezyogotic

Reproductive isolation

Aerobes

Require oxygen to live

Pheromones

Responsible for attracting adjacent hyphae of different mating types

Evolution

Scientific viewpoint Descent with modification

Prokaryotic

Single celled organism

Plasmodial slime molds

Slime molds are brightly pigmented and have a single mass of cytoplasm with many nuclei.

Cellular

Slime molds can function as single cells or can form aggregates of cells that function as a unit if food is depleted.

Soredia

Small clusters of hyphae with embedded algae

Biological Species Concept

Species is a group of populations whose members have the potential to produce fertile offspring.

Homologous

Structures in different species that are similar because of common ancestry.

Hyphae

The branching, threadlike tubes that make up the bodies of multicellular fungi

Plasmogamy

The union of the cytoplasm of two parent mycelium

Brown Algae

These are photosynthetic and are the largest and most complex of the stramenopile group.

Oomycetes

These cause potato blight and tend to be decomposers and parasites.

Parabasalids

They have flagella and an undulating membrane

Kinetoplastid

Trypanosoma causes sleeping sickness and uses a "bait-and-switch" tactic to avoid detection by its hosts antibodies and it is a

Microsporidia

Unicellular parasites of animals and protists that do not have conventional mitochondria

Chytrids

Unique among fungi in having flagellated spores, called zoospores

Individuals

With certain heritable traits survive and reproduce at a higher rate than other individuals *do not evolve; populations evolve over time *natural selection acts on individuals

Ectomycorrhiza

Wraps itself around the plant root

Peptidoglycan

a network of sugar polymers cross-linked by polypeptides

Heterotrophy

an organism that cannot synthesize its own food and is dependent on complex organic substances for nutrition. Organisms called mixotrophs can obtain nutrients/energy from

Gram-negative

bacteria have less peptidoglycan and an outer membrane that can be toxic

Gram-positive

bacteria have simpler walls with a large amount of peptidoglycan

Mycoplasmas

bacteria of the Mycoplasma genus that are found in humans and have no cell wall; the smallest free-living organisms presently known being intermediate in size between viruses and bacteria.

Morphological Species Concept

characterizes a species by body shape and other structural features

Mixotrophs

combine photosynthesis and heterotrophic nutrition

Phylogenetic Species Concept

defines a species as the smallest group of individuals that share a common ancestor

Disruptive Selection

form of natural selection in which a single curve splits into two; occurs when individuals at the upper and lower ends of a distribution curve have higher fitness than individuals near the middle

Ectomycorrhize

fungus *surrounds root cells and root tips

Ecological species concept

identifies species in terms of their ecological niches, focusing on unique adaptations to particular roles in a biological community

Penicillin

is a group of antibiotics which include penicillin G, penicillin V, procaine penicillin, and benzathine penicillin. They are derived from Penicillium fung

Chemotaxis

is the movement toward or away from a chemical stimulus

Conjugation

is the process where genetic material is transferred between prokaryotic cells

Parasitic Chemoheterotrophs

live in or on the body of a host responsible for many humans diseases

Radiolarians

marine protists; have tests fused into one delicate piece, usually made of silica; use their pseudopodia to engulf microorganisms through phagocytosis

Obligate Aerobes

organisms that require a constant supply of oxygen in order to live

Nitrosamonas

oxidises NH4 into NO2- (nitrite)

Descent with modification

principle that each living species has descended, with changes, from other species over time

Cercozoans

threadlike pseudopodia

Photoautotrophy

use light energy and carbon dioxide to craete energy rich carbon compounds

Ecological Species Concept

views a species in terms of its ecological niche