Bio II Exam #2

Virus

nucleic acid in a protein coat

lack metabolic structure or functioning outside of host cell

some illnesses preventable by vaccine (not antibiotics)

Virus used what for reproduction

host cell

Vaccine

weakened virus/ protein to trigger immune response

Prokaryotes

Domains: Bacteria & Archaea

most numerous organisms on Earth

Tremendous diversity

Physiology adapted to environment

Lack membrane bound organelles

generally single celled

0\.5-5 um diameter

Prokaryote common shape

Cocci, Bacilli, Spirilla

Cocci

sphere

diplococci- in pairs

streptococci- chains of many cells

staphylococci- grape-like cluster

Bacilli

rod

streptobacilli- chains

Spirilla

spiral shaped

spirochete- corkscrew

Prokaryote cell wall

protection

Bacteria-peptidoglycan, gram-positive, gram-negative

Archaea

Peptidoglycan

polymer of sugars, amino acids

gram-positive

stain purple, 1 external layer of peptidoglycan

gram-negative

stains pink, peptidoglycan sandwiched b/w membranes- can have higher drug resistance

Archaea

structurally similar to Bacteria but chemically different

Capsule

External layer of polysaccharides and proteins

\-help bacteria to attach to surfaces and each other

\-aid in formation of biofilms

\-may cause disease, help digest food in Lg intestine, cycle nutrients in ecosystem, aid plant growth

Prokaryote Flagellum

tail-like structure

not a cytoskeleton extension like eukaryotic flagella

Taxis- directed movement towards or away from stimuli

Pili and Fimbriae

short hair-like structures, holds separate cells together

Archaea

Extreme halophiles- salt loving

extreme thermophiles- hot loving

Methanogens-produce methane in anoxic environments in wetlands & intestines of some animals including humans

Protist Diversity

Most are unicellular

some colonial, others multicellular

Aquatic or moist environments

Protist motility

motility during all or some of life cycle

Flagella- One or more tail-like structure

Cilia- short hairs

Pseudopods- false feet

Protist Internal/External structure

Diatoms- cell wall embedded w/ silica

Radiolarians- Silica in cytoskeleton

Thallus- plant like form, seen in Brown algae

What group are plants grouped among

Archaeplastids

How long have plants been on land

500 mya

ancestors were aquatic algal species

plants are

multicellular

eukaryotic

mostly photosynthetic autotrophs

cell walls w/ cellulose

Alternation Generation

Diploid Sporophyte

Haploid spores

Haploid Gametophyte

Haploid gametes

Diploid Sporophyte

Nonvascular land plants

Phylum Hepatophyta -Liverworts

Phylum Bryophyta -mosses

Phylum Anthocerophyta -Hornworts

Vascular Land plants

most plants

has specializes tissue to conduct water and nutrients throughout plants

Seedless Vascular plants

Phylum Lycophyta

Phylum Monilophyta

Seed Plants

Gymnosperms & Angiosperm

Gymnosperm

Phylum Ginkgophyta

Phylum Cycadophyte

Phylum Getophyta

Phylum Coniferophyta

Angiosperms

Flowering

Phylum Anthophyta

Cotyledon- seed leaf

monocot-one seed leaf

eudicot- two seed leaf

Vascular plants have

Xylem, Lignin, Phloem

Xylem

Conduct water and minerals from roots

Lignin

complex molecule w/ variable forms

\-provides structural support and helps conduct water

Phloem

conducts sugar, amino acids, etc. from leaves

Plants- Form Fits function

Roots, Stems, and leaves

Roots

Anchor to substrate

Absorb water and minerals

lg surface area

carbohydrate storage for some

symbiotic mycorrhizae

Stem

aerial support for leaves, flowers, and fruits

modified stems for:

food storage

asexual reproduction

lateral spreading, storage

apical buds

axillary buds

apical buds

at the tip of a shoot or branch

axillary buds

along a shoot or branch, behind or below apical buds

Leaves

inc surface area for photosynthesis gas exchange, transpiration

modified leaves for:

energy storage- buds

sexual reproduction- flowers

support-tendrils

protection- spines

asexual reproduction

Meristems

region where tissue actively dividing undifferentiated cells

Apical meristems

growth in length (primary growth)

in apical buds, axillary buds, and root tips

Lateral meristems

growth in diameter (secondary growth)

Vascular Cambium

Adds xylem and phloem

Shoot Growth

Apical dominance- apical bud inhibits growth of axillary buds

animal browsing or pruning inc. axillary growth-more bushy form

Root growth

apical meristem tissue protected by hard root cap

secreted polysaccharide slime lubricated tip

Bud Scar

site of previous years apical bud

Sapwood

newer secondary xylem, continues to transport

Heartwood

older, non-transporting secondary xylem

older phloem tissue ruptures as tree diameter grows

Bark

all tissue exterior to the vascular cambium

Annuals

complete life cycle in one year

Biennials

complete life cycle in two years

Perennials

live many years

Fungi grouping

Opisthokonts

supergroup- Unikonta

likely evolved from single-celled protists

Yeast

single celled form

Hyphae

long filaments consisting of many cells or single cell w/ hundreds of nuclei

\-cell walls contain chitin for strength and flexibility

Mycellium

hyphae growing through substrate to absorb nutrients

Fungi human benefits

food

antibiotics

genetic research

Animal grouping

Opisthokonts

supergroup- unikonta

Choanoflagellates-clostest living relative

Porifera

no true tissue, no symmetry

“pore-bearer”

evolutionary dead end

sessile-stay in place

most marine, some freshwater

\-lack nerves & muscles

react to environment by closing pores & osculum

Porifera: Amoebocyte cells

collect food, secreted gelatinous matrix, collect waste

produce spicules- skeletal fibers

Porifera: Choanocyte cells

circulate water

Porifera: Subkingdom- Eumetazoa

Have true tissue & body Symmetry

radial symmetry- most sedentary or passively drifting

diploblastic-two tissue layer

outer epidermis

inner gastrodermis

Phylum Cnidaria

hydra, jellyfish, corals, sea anemones

have contractile tissue & non-centralized nerve net

Primary forms of cnidaria

Polyp- most sessile, cylindrical body, attach to substrate

medusa- free moving, jellyfish-like, umbrella shape

Bilateral Symmetry

symmetry b/w left & right sides

distinct anterior, posterior, dorsal, & ventral

most active, travel headfirst through environment

Triploblastic- have three tissue layers

anterior

front

posterior

rear

dorsal

top

ventral

bottom

Triploblastic layers

Ectoderm- outer covering & central nervous system in some phyla

Endoderm-lines the digestive tract, lungs, liver

Mesoderm- muscle & most o/ internal organs

Embryonic development

archenteron, protostomes, Deuterostomes

Archenteron

cavity of gastrula, becomes the gut

protostome

“proto”-first, “stoma”-mouth

\-blastopore- opening in gastrula stage, becomes mouth

Deuterostomes

“deutero” = second

Blastopore becomes anus

Body cavity

space b/w the digestive tract body wall

cushions the internal organs & enables them to grow and move independently

Acoelomate, Pseudocoelomate, Coelomate

Acoelomate

no body cavity

Pseudocoelomate

“false” body cavity- not completely lined w/ mesoderm derived tissue

Coelomate

true body cavity- cavity completely lined w/ mesoderm derived tissue

Phylum Platyhelminthes

platy- = “flat”, helmis- = “worm”

acoelomates in marine, freshwater, damp habitat

Platyhelminthes classes

Turbellaria, trematoda, cestoda

turbellaria

free-living flat worms

\-planaria

Trematoda

parasitic flatworm

\-Fluke

cestoda

parasitic flatworm

\-tapeworm

Phylum Nematoda

Roundworms from 1mm to 1m length

pseudocoelomates

most free-living, important decomposers

some parasitic: heartworms, trichinella-trichinosis

Phylum Annelid

Coelomates

Anellus= “ring”

segmented body-repeating units (earthworms, leaches)

terrestrial, marine, freshwater

earthworms decompose organic matter, soil aeration

Phylum Mollusca

Coelomates

soft body, most have hard calcium carbonate shell

Mollusca Classes

Gastropoda, Bivalvia, Cephalopoda

Class Gastropoda

“belly fat”

snails, slugs, sea slugs

fresh water, salt water, terrestrial

Class Bivalvia

“double folding doors”

clams, oysters, mussels, scallops

Class Cephalopoda

“head foot”

tend to be fast, predators

Octopi lack shells

squids have small internal shells

Phylum Arthropoda

Means “jointed foot”

appendages specialized for walking, feeding, sensory, defense,

Lobsters, spiders, insects, etc.

80% of living animal species

exoskeleton (protein & chitin)

Arthropoda Subphylum’s

Chelicerata, Myriapoda, Crustacea, Hexapoda

Subphylum Chelicerata

feeding appendages used as pincers or fangs

lack antennae, have 4 pairs of legs on cephalothorax

\-Class Arachnida- spiders, scorpions, ticks, mites

most terrestrial

Subphylum Myriapoda

\-Class Chilopoda

\-centipedes

\-carnivores

\-1 pair legs per segment

Class Diplopoda

\-millipedes

\-decomposers- decaying plants

\-2 pair legs per segment

Subphylum: Crustacea

crab, shrimp, lobster, crayfish, barnacles, krill

most aquatic

\-includes terrestrial “pill bugs” and others

many appendages, some on abdomen

Subphylum: Hexapoda

3 pairs of legs

Class Insecta- butterflies, bees, beetles

Mostly terrestrial or fresh water

Phylum Echinodermata

“Spiny Skin”

sand dollars, sea urchins, sea star

most slow-moving or sessile

marine

adults-near-radial symmetry

\-bilateral larvae

move using water vascular system

\-water-filled canals branch into tube feet

some capable of regeneration

Chordata distinct features in embryos

Dorsal hallow fin

Notochord-flexible, supportive, rod b/w digestive tract and nerve chord

pharyngeal slits or clefts

post-anal tail

Chordata Subphylum’s

Cephalochordata & Vertebrata