Biology Exam 3 prep

accidental host

an organism in which the pathogen is not normally found, but can serve as a host. Typically the pathogen is more virulent in accidental hosts

balanced pathogenicity

capsid

RNA virus

virus

antibiotic

chicken pox

enveloped virus

herd immunity

lysogenic cycle

polio

smallpox

influenza virus

lytic cycle

SARS-CoV2

zoonotic disease

alternation of generations

artificial selection

Directed breeding (of plants and/or animals) for useful traits (e.g. kernel size, milk production, plant height, etc.)

cuticle

The waxy, waterproof layer that covers the leaves and stems of most plants.

endosperm

triploid (3n) tissue found in angiosperm seeds that is the product of double fertilization (1 sperm + 2 polar nuclei = 3n endosperm)

meiosis

cell division that results in four haploid daughter cells each with half the number of chromosomes of the diploid parent cell, as in the production of animal gametes and plant spores. The daughter cells are genetically diverse - different from each other and the parent cell.

pollen

the tiny granules that contain the male gametophyte of seed plants. This stage replaces the flagellated sperm seen in non-seed plants (ferns and moss)

sporangia

plant structure located on the mature sporophyte. this is where meiosis occurs, producing haploid spores. (Sori on fern leaves = clusters of these)

stomata

Small openings on the underside of a leaf through which oxygen and carbon dioxide can move. These are regulated to control gas exchange and limit water loss.

angiosperm

flowering plant that produces seeds within a fruit. These plants have double fertilization as part of their life cycle, so produce triploid endosperm in their seeds.

bisexual gametophyte

haploid plant stage that makes both eggs and sperm on the same plant (homosporous plants have these)

diploid

abbreviated 2n - indicates that this organism has paired chromosomes, so 2 of each chromosome.

fern

seedless vascular plant that has a flagellated sperm (not pollen), small bisexual gametophyte and large sporophyte stage.

homosporous (homospory)

plants that produce a single type of spore that grows into a gametophyte that produces both eggs and sperm (bisexual gametophyte)

microspores

spores made by a heterosporous plant - these are the smaller ones that grow into the male gametophyte.

pollination syndrome

flower characteristics associated with a particular type of pollinator. This is the result of coevolution of flower and pollinator

sporophyte

multi-cellular diploid (2n) phase of an organism. Makes haploid spores by meiosis.

antheridia

male gametangia (protected gamete producing structure) that develops flagellated sperm (seen in mosses/bryophytes)

bryophyte

a general term for a group of seedless nonvascular plants (e.g. mosses, liverworts, or hornworts)

double fertilization

fruit

The ripened/enlarged ovary of an angiosperm that surrounds seed(s). Often used for protection and dispersal

gymnosperms

Seed plant that produces seeds without endosperm, flowers, or fruit. "naked seed plant"

lignin

substance in vascular plants that makes cell walls rigid (this is what enables trees to get so tall)

mitosis

primary producer

An autotroph, usually a photosynthetic organism that makes carbon available to consumers (herbivores and the carnivores that eat them)

sporopollenin

compound that protects plants in a harsh terrestrial environment - coats spores and pollen

triploid

tissue with 3 sets of chromosomes (3n)

archegonia

carpel

female reproductive organs of a flower (stigma, style, and ovary)

gametangia

protected region in which gametes and zygotes develop and which prevents drying out (in mosses and ferns)

haploid

petals

flower parts that are colorful to attract pollinators

stamen

Male part of the flower; made up of an anther and a filament.

secondary metabolites

organic compounds that are not directly involved in the normal growth, development, or reproduction of plants- these often have bioactivity in animals (and are often used as medicines - e.g. salicylic acid produced by willows is the active ingredient in aspirin)

monecious plants

plants that have both male and female structures in the same plant (flower)

dioescious plant

perfect flowers

imperfect flower

monocot

dicot

mychorrhizal fungi

basidospore

spore formed in club fungi (basidomycetes) - product of meiosis from the diploid hyphae that form the "mushroom".. genetically diverse

dimorphic fungi

may grow as hyphae or yeast - these fungi are often associated with disease in humans

extracellular digestion

lignin

saprophytes

Ascomycete

Member of a group of fungi characterized by saclike structure called an ascus (sac) that produce 8 diverse spores in sexual reproduction. Most of its hyphae are dikaryotic

carbon cycle

The circulation of carbon from the atmosphere (carbon dioxide) into organisms (photosynthesis/fixation) and back again (decomposition)

commensal

zygospore

heterokaryotic

A fungal life cycle stage that contains two genetically different nuclei in the same cell.

mutualism

A relationship between two species in which both species benefit

spore

ascospore

cellulose

conidia

fungal spores that are made asexually (genetically identical/very similar)

septate

coenocytic

parasitic

soredia

Basidomycetes

include mushrooms, puffballs, and shelf fungi - produce gilled mushrooms (like the ones on pizza) and make 4 spores via meiosis when sexually reproducing

chitin

decomposer

organism that breaks down and obtains energy from dead organic matter (returns organic molecules to their inorganic state)

yeasts

single-celled fungi that reproduce by budding

mold

mycelium

plasmogamy

karyogamy

zygomycetes

accidental host

an organism in which the pathogen is not normally found, but can serve as a host. Typically the pathogen is more virulent in accidental hosts

balanced pathogenicity

Host-parasite relationship in which the parasite persists in the host while causing minimal harm - host becomes more resistant while pathogen becomes less virulent

capsid

protein coat surrounding a virus

RNA virus

A virus in which the genetic information is stored in the form of RNA (as opposed to DNA).

virus

A tiny, nonliving particle that invades and then reproduces inside a living cell. It steals host ATP, protein production, and nucleic acid replication machinery.

antibiotic

A chemical secreted by a living organism that kills or reduces the reproduction rate of other organisms. Effective against bacteria, but do nothing to treat viruses.

chicken pox

DNA virus that causes both chicken pox, becomes latent, then can cause shingles.

enveloped virus

A virus enclosed within a phospholipid membrane derived from its host cell.

herd immunity

the resistance to the spread of a contagious disease within a population that results if a sufficiently high proportion of individuals are immune to the disease, especially through vaccination.

lysogenic cycle

A phage replication cycle in which the viral genome becomes incorporated into the bacterial host chromosome as a prophage and does not kill the host.

polio

a paralytic viral infection of the gray matter of the spinal cord - prevented with the Salk or Sabin vaccine.

smallpox

The overall deadliest known disease in the history of the world. In the 20th century alone there were approximately 500,000,000 people who died of this disease. This disease was eradicated in the 1980s

influenza virus

Enveloped, ssRNA, w/ segmented genome. Contain hemagglutinin (promotes viral entry) and neuraminidase (promotes progeny virion release) Ags. Responsible for worldwide influenza epidemics; pt at risk for fatal bacterial superinfeciton. Rapid genetic changes.

lytic cycle

A type of viral (phage) replication cycle resulting in the release of new phages by lysis (and death) of the host cell.

SARS-CoV2

Potentially life-threatening viral infection that usually starts with flulike symptoms - COVID-19 is caused by SARS-CoV2. Pandemic in 2020. (Has killed ~7 million worldwide from 2019-2023)

zoonotic disease

a disease communicable from animals to humans under natural conditions; also know as zoonosis