BIOL 117 - Exam 2

monophyletic group

common ancestor and all of its decendants

paraphyletic group

common ancestor an some of its decendants

all

are protists fungal-like, animal-like, or plant-like?

all eukaryotic

are protists eukaryotic, prokaryotic, both?

all

are protists unicellular or multicellular or live in colonies?

both

do protists reproduce sexually or asexually?

they cause disease, bottom of food chain

why do we study protists?

protists

they have nuclear membrane and endomembrane organelles

endosymbiosis theory

a host cell engulfs a bacterium, and bacterium survives and produces ATP for the host cell

secondary endosymbiosis

a predatory protist engulfs a photosynthetic protist, and that photosynthetic protist loses its nucleus but the chloroplast remains

amoebozoa

protist: fungal-like, feed on microorganisms on decaying vegetation, uses pseudopodia for movement and feeding, single cell with thousands of nuclei, no cell walls, can learn (ex. plasmodial slime mold)

opisthokopta

protist: unicellular but live in colony, cells have a single flagellum to move and bring food in, animal-like, closest living relatives to animals, studied to learn about evolutionary origins of multicellularity (ex. choanoflagellates)

excavata

protist: causes diarrheal illness when ingested in contaminated water, calls have feeding groove where food is ingested, lack mitochondria (ex. giardia lamblia)

plantae (archaeplastida)

protist: can be unicellular, colonial, or multicellular, photosynthesize, plant-like, closest living relatives to land plants, significant source of energy for humans (ex. green algae)

rhizaria

protist: calcium carbonate shells, found in limestone, do not actively move, just float, have thin pseudopodia to feed (ex. foraminifera)

alveolata

protist: small aquatic organisms called plankton, primary producers and consumers, important to carbon cycle, have outer coverings made from cellulose, bioluminescent, cause red tides, can accumulate in seafood, so eat with caution (ex. dinoflagellates)

stramenopila

protist: unicellular, photosynthetic, impact on carbon cycle, major food source in aquatic environments, cell wall composed of silica so glass-like, switch from asexual to sexual reproduction (ex. diatoms)

nutrients for land plants, role in carbon cycle, health, economic impacts

why study fungi?

eukaryotic

are fungi prokaryotic or eukaryotic?

yeast

what type of fungi is single-celled?

networks of branching filaments

what type of fungi is multicellular?

hyphae

cells that have a cell wall made of chitin

both

do fungi undergo sexual or asexual reproduction?

asexual reproduction

mitosis to produce spores in fungi

plasmogamy

sexual reproduction in fungi in which there is fusion of the cytoplasm of two hyphae from different individuals (n)

heterokaryotic mycelium

sexual reproduction in fungi in which the cells contain two haploid nuclei from different parents or mating types (n+n)

karyogamy

sexual reproduction in fungi in which there is fusion of nuclei from different mating types results in a zygote (2n)

zygosporangia

reproductive structure of fungi in which spore-producing structures formed when hyphae are yoked

basidia

reproductive structure of fungi in which there are little pedestals where meiosis occurs and spores form

asci

reproductive structure of fungi in which there are sacs where meiosis occurs and spores form

reproductive structures

how are fungi lineages divided?

saprophytic

fungi metabolic strategy: digest organic material (decomposition)

parasitic

fungi metabolic strategy: absorb nutrients from living host, giving nothing in return

lichen-forming

fungi metabolic strategy: live in association with green algae, helps plants resist stresses

endophytic

fungi metabolic strategy: live inside of land plants in above ground areas in a mutualistic relationship

mycorrhizal

fungi metabolic strategy: live in association with plant roots

chytrid

fungi: parasite of amphibians, reproduces with swimming gametes and spores that form under the skin of frogs, other species can be parasites of insects or mutualists of cows, deer, and other mammals to digest plant material

zygomycetes

fungi: sexual reproduction occurs when spore structure formed when two individuals meet and hyphae yoke together, asexual reproduction also common, live as saprophytes on bread, fruits, and vegetables

glomeromycota

fungi: form arbuscular mycorrhizal associations, cannot live without plant hosts, get sugars from plants and provide mineral nutrients for them, asexually reproduce

basidiomycota

fungi: mushrooms contain sexual reproductive structures, many form ectomycorrhizal associations, other are saprophytic and rot wood, many mushrooms are toxic

ascomycota

fungi: parasite of insects, cause strange behavior in host insects, other species are lichen-forming or form mycorrhizal associations

eukaryotes

are animals prokaryotes or eukaryotes?

multicellular

are animals unicellular or multicellular?

monophyletic

do animals form a monophyletic or paraphyletic group?

ectoderm

“outer skin”, gives rise to skin and nervous system

endoderm

“inner skin”, gives rise to lining of the digestive tract and organs that connect to the digestive tract such as the liver

mesoderm

“middle skin”, gives rise to circulatory system, muscle, and internal structures such as bones and most organs

triploblastic

animals that have all three embryonic tissue types

diploblastic

animals that have ectoderm and endoderm only

radial symmetry

body plan that is based upon a cylinder or sphere, with the body organization in pie-shaped wedges arrayed around a central point

bilateral symmetry

body plan where two sides are mirror images of each other

nerve net

found in animals with radial symmetry, no brain, more likely to encounter prey and sense the environment in any direction

central nervous system

found in animals with bilateral symmetry, clusters of nerves, coincides with cephalization

cephalization

the animal has a head and a central nervous system

coelom

fluid filled cavity where nutrients circulate and organs move freely (aka body cavity)

acoelomate

animals that have no enclosed body cavity

coelomate

animals that have an enclosed body cavity completely lined with mesoderm

pseudocoelomate

animals that have an enclosed body cavity partially lined with mesoderm

gastrulation

rearrangement of cells to form an animals gut

protostomes

the pore becomes the mouth in gastrulation, block of solid mesoderm splits to form coelom

deuterostomes

the pore becomes the anus in gastrulation, mesoderm pockets pinch off of gut to form coelom

open and closed

what types of circulatory systems can animals have?

complete, incomplete, and absorption

what types of digestive systems can animals have?

hydrostatic, endoskeleton, exoskeleton

what types of skeletal systems can animals have?

external, internal

what types of fertilization can animals have?

oviparous

lay fertilized eggs, embryos nourished by yolk

viviparous

nourish embryos internally, give birth to live young

ovovipiparous

retain eggs, embryos nourished by yolk, give birth to live young

porifera

animals: sponges are filter feeders

ctenophora

animals: most comb jellies are planktonic (small, floating)

cnidaria

animals: stinging cells of anemones, jelly fish, and corals capture prey

platyhelminthes

animals: flatworms, commonly live in marine and freshwater environments

annelida

animals: segmented worms

mollusca

animals: snails, clams, octopus, squid, soft bodies with a foot, visceral mass, and a mantle some have calcium carbonate shells

nematoda

animals: roundworms named for cylindrical body

arthropoda

animals: crustaceans, spiders, scorpions, centipedes, and insects, exoskeletons and open circulatory systems

insecta (arthropoda)

animals: 3 body segments, 6 legs, 2 pairs of wings

echinodermata

animals: sea urchins, starfish

chordata

animals: not all chordates are vertebrates, but most have vertebrae and skulls

mammalia (chordate)

animals: fur, teeth on upper and lower jaws, and milk production, monotremes, marsupials, and eutherians

stem cells

undifferentiated cells that can become almost any cell type in the body

cleavage

rapid cell divisions

gastrulation

cells move and rearrange to form three layers

organogenesis

tissue and organ formation, forming a neural tube from ectoderm, somites form from mesoderm

apoptosis

programmed cell death (normal toes - webbed toes)

cell differentiation

the process of becoming a specialized cell type

morphogens

establishes anterior-posterior gradient of embryo

gap genes

organize cells into groups of segments along anterior-posterior axis

pair-rule genes

organize cells into individual segments

segment polarity genes

establish anterior-posterior gradient within each segment

homeotic genes

trigger development of structures

effector genes

change proliferation, death, movement, and differentiation of cells

hox genes (homeotic genes)

a group of related genes that specify regions of the body plan of an embryo along the head-tail axis of animals

anatomy

the study of an organism’s physical structure or form

physiology

the study of how the physical structures in an organism function

adaptation

heritable traits that allow individuals to survive and reproduce in a certain environment better than other individuals that lack those traits

fitness trade off

when a trait is good for one reason, but bad for another reason (ex. peacock feathers are good for mating, but make them visible to predators)

acclimation

phenotypic change due to short-term environmental changes, is reversible

molecular level

correlations between function and form: enzymes have a specific shape to accept substrates

cellular level

correlations between form and function: white blood cells have many lysosomes