Biology 1111 Lab Midterm 1

Symbiosis

A close relationship between two species that benefits at least one of the species

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

gram stain

A staining method that distinguishes between two different kinds of bacterial cell walls

How do fungi acquire their nutrients?

All fungi are heterotrophic organisms that obtain their nutrients by absorption, digesting their food outside their bodies and absorbing the digestion products into their cells most are saprophytic: feed on dead organic matter some are parasitic: feed on living hosts

How is genetic material stored in bacteria?

Bacteria do not have chromosomes Their genetic material is a single circular molecule of DNA In addition, bacteria may have smaller rings of DNA called plasmids

nonvascular plants

Bryophytes, such as mosses and liverworts, that have no vascular tissue and either occur in moist locations or have special adaptations for living in dry locations

Terminology used in describing bacterial colonies

Common colony shapes: punctiform (under 1 mm diameter) round filamentous irregular Common colony margins: smooth (entire) curled wavy lobate filamentous Common colony surface characteristics: smooth concentric wrinkled contoured

sporophyte

Diploid (2n), or spore-producing, phase of an organism, makes haploid spores by meiosis

Taxonomy classification systems for Fungi

Domain > Supergroup > Clade > Kingdom > Phylum > Genus >Species

Describe how fungi reproduce

Fungi often have complex life cycles with alternating sexual or asexual (vegetative) reproduction they may produce spores either asexually by mitosis or sexually by meiosis When reproducing sexually, fungi produce reproductive structures called fruiting bodies made of closely interwoven hyphae Sexual spores form in these fruiting bodies

gametophyte

Haploid (n), or gamete-producing, phase of an organism, haploid gametes are produced by mitosis

Symbiotic relationship between fungi and bacteria

In ecosystems, fungi share with bacteria the essential role of decomposition, returning to the ecosystem the nutrients trapped in dead organisms

homospory

Production of a single type of spore. In the nonvascular plants (Bryophytes) and most of the seedless vascular plants gives rise to the gametophyte by mitosis

hyphae

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

antibiotic

a chemical produced by a bacterium or fungus that has the potential to control the growth of another bacterium or fungus

peptidoglycan

a complex protein-carbohydrate polymer the most common component found in the cell wall of organisms in the domain Bacteria

binary fission

a form of asexual reproduction used by Bacteria the cell duplicates its components and divides into two cells these cells usually become independent, but they may remain attached in linear chains or grape like clusters

nutrient broth/agar

a general purpose, nutrient medium used for the cultivation of microbes supporting growth of a wide range of non-fastidious organisms Nutrient agar is popular because it can grow a variety of types of bacteria and fungi, and contains many nutrients needed for the bacterial growth

clades

a group of species, all of which are descended from one ancestral species, representing one phylogenetic group scientists performing phylogenetic studies have suggested that grouping organisms into clades can be meaningful for indicating evolutionary relationships

sporophyll

a leaf that bears sporangia

thallus

a lichen body varies in shape and colors

meiosis

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of plant spores.

bacterial lawn

a uniform, even layer of organisms covering an entire surface

cuticle

a waxy covering on a plant body that prevents desiccation

monophyletic clade

all of the descendants came from one common ancestor

Taxonomy

an important branch of biology that deals with naming and classifying organisms into distinct groups or categories

zone of inhibition

area around disk where bacteria growth has been inhibited

community succession

as one community grows, it modifies the environment, and a different community develops as a result

most bacteria can be classified to three basic shapes

bacilli (rods) cocci (spheres) spirilla (spirals, or corkscrews)

ovary

base of carpel; protects ovules inside, matures to form the fruit

pathogenic bacteria

cause diseases in humans and other animals

mitosis

cell division in which the nucleus divides into nuclei containing the same number of chromosomes

gram-negative bacteria

cell wall contains less peptidoglycan more complex cell wall, containing various polysaccharides, proteins and lipids retain safranin appear pink/red

prokaryotes

cells that lack a membrane bound nucleus and membrane bound organelles have existed on Earth longer and are more widely distributed than any other organismal group found in almost every imaginable habitat: air, soil, and water, in extreme temperatures and harsh chemical environments can be photosynthetic, using light as the source of energy, or chemosynthetic, using inorganic chemicals as the source of energy most are heterotrophic, absorbing nutrients from the surrounding environment

taxonomy

classification systems For Protists: Domain > Supergroup > Clade > Subclade > Class > Order > Family > Genus > Species

sori

clusters of sporangia

petal

colored, white, or even greenish whorl of bracts located just inside the sepals

paraphyletic clade

consists of an ancestral species and some, but not all, of the descendants

Phylogeny

evolutionary history as scientists began to understand the processes of genetics and evolution by natural selection, they realized the value of classifying organisms based on phylogeny

three ways protists move

flagella (tail) cilia (hairlike structures) pseudopodia (projections coming out of the organism's body)

angiosperms

flowering plants flower pollination is mediated by specific agents- insects, birds, and bats- in addition to water and wind this process can enhance opportunity got cross-fertilization amount distant plants and therefore the possibility of increase genetic variation

angiosperm reproduction

follows the trend for reduction in the size of the gametophyte the pollen grain contains the male gametophyte and the multinucleate embryo sac is all that remains of the female gametophyte this generation continues to be protected and dependent on the adult sporophyte plant

food vacuoles

form at the end of a gullet may appear as dark vesicles throughout the cell digestive function

Mycorrhizae

fungi have a mutualistic association with roots of most plants, forming mycorrhizae Mycorrhizal fungi increase the plant's ability to capture water and provide the plant with minerals and essential elements In turn, the plants supply the fungi with nutrients such as carbohydrates

In what form do fungi store carbohydrates?

glycogen

photosynthetic algae

green algae divided into two main groups: chlorophytes and charophytes charophytes most closely related to plants

bacterial colony

grows from a single bacterium and is composed of millions of cells each colony has a characteristic size, shape, consistency, texture, and color (colony morphology), all of which may be useful in preliminary species identification

vascular plants

have tissues made of cells that transport water and nutrients throughout the plant

two things for defining protists

how they move around how they eat and obtain energy

streak plate method

isolates bacterial colonies

Where is the female gametophyte in a gymnosperm?

it is retained within the sporangium in the ovule of the sporophyte generation

sterilization

kills all bacteria

megaspores

large spores that divide by mitosis to produce the female gametophyte

chitin

makes up the cell walls of hyphal cells

pollen grain

male gametophyte in seed plants desiccation resistant and adapted primarily for wind pollination, removing the necessity for fertilization in a watery medium

mycelium

mass of hyphae

How can fungi be distinguished from bacteria?

may be distinguished by the fuzzy appearance of the colony the body of a fungus is a mass of filaments called hyphae in a networked called a mycelium

phenol coefficient

method of evaluating the effectiveness of a disinfectant or antiseptic that compares the agent's efficacy to that of phenol

aseptic technique

method used to make the environment, the worker, and the patient as germ-free as possible

microspores

numerous small spores that produce the male gametophyte by mitosis

Eukaryotes

organisms made up of one or more cells that have a nucleus and membrane-bound organelles

sepal

outer whorl of bracts, which may be green, brown, or colored like the petals; may appear as small scales or be petal-like

three ways protists acquire energy

photosynthesis, photoautotrophy (plant like protists) heterotrophy (ingest things) mixotrophy (both combined) -eating and getting energy from photosynthesis

seed

plant embryo and a food supply encased in a protective covering

alterations of generations

plants life cycle where they alternate between a haploid gametophyte generation and a diploid sporophyte generation these two generations differ in morphology, but they are still the same species in all plants except the bryophytes (mosses and liverworts), the diploid sporophyte generation is the dominant generation

anther

pollen producing structure

heterospory

production of two kinds of spores occasionally seen in seedless vascular plants

unicellular eukaryotic organisms

protists meaning a general term, not a taxonomic cateogry

stigma

receptive tip of the carpel, where pollen is places

Gymnosperm Coniferophyta

seed bearing plants, naked seeds

Gram Staining Procedure

set out a clean slide placed drop of liquid bacteria on the slide and let it air-dry once dry, hold the slide with a clothespin and pass it quickly over the flame of an alcohol lamp and let it warm the slide support the slide on the staining tray and cover the smear with three or four drops of crystal violet, wait 1 minute rinse the stain gently into the staining pan with water cover the smear with gram iodine for 1 minute rinse again with water destain by dropping the 95% alcohol/acetone mixture one drop at a time at first a lot of violet color will rinse away, continue adding drops until only a faint violet color is seen in the alcohol rinse the alcohol/acetone removes the crystal violet stain from the gram negative bacteria the gram positive bacteria will not be destained rinse with water to prevent further destaining cover the smear with safranin for 30-60 seconds. this will stain the destained gram-negative bacteria a pink/red color. the gram positive bacteria will be unaffected by the safranin

prokaryotic

single-celled organisms

Bacteria

small, relatively simple, prokaryotic single celled organisms

Plasmids

smaller rings of DNA consisting of only a few genes in bacteria

filament

stalk that supports the anther

carpel

structure in which ovules are enclosed in angiosperms

Alterations of generations plant life cycle

the diploid sporophyte undergoes meiosis to produce haploid spores in a protective, nonreproductive multicellular structure called the sporangium diving by mitosis, the spores germinate to produce the haploid gametophyte the gametophyte produces gametes inside a multicellular structure made of nonreproductive cells, forming gametangia There are two types of gametangia: eggs are produced by mitosis in archegonia and sperm are produced in antheridia The gametes fuse (fertilization), forming a diploid zygote The zygote divides by mitosis to produce the multicellular embryo and then the mature sporophyte of the next diploid generation

what is the dominant generation for fungi?

the haploid gametophyte generation

stomata

the small openings on the undersides of most leaves through which oxygen and carbon dioxide can move

gram-positive bacteria

thick peptidoglycan cell wall layer simple cell wall retain crystal violet/iodine appear blue/purple

style

tissue connecting stigma to ovary

endosperm

tissue that allows the female gametophyte to provide nutrients for the developing sporophyte

pasteurization

treating a substance with heat to kill or slow the growth of pathogens

rhizome

underground stem

contractile vacuole

used for water balance fill and collapse as it expels water from a cell

antiseptics

used to control and reduce bacteria on living tissue such as skin

disinfectants

used to control and reduce bacterial growth on inanimate objects