uab gibbons bio 2 lecture exam

what are the two plant hormones?

auxin and gibberellins

how do animals respond to the environment?

movement

how do plants respond to the environment?

altering growth and development

what are factors that plants sense and respond?

plants recieve/respond to signals from the environment, like sunlight

what is the term for physical adaptations for growing in darkness?

etiolation

what does a plant undergo after exposure to light, in which roots and shoots grow normally?

de-etiolation

what are the stages of cell signal processing?

reception, transduction, response

reception

phytochrome is the receptor that detects the stimulus(light)

transduction

second messengers transfer and amplify the signals from the receptor

response

this leads to regulation of one or more cellular activites, like increased enzyme activity, function in photosynthesis directly, supply the chemical precursors for chlorophyll production, affect the levels of plant hormones that regulate growth

how do plants communicate with the external environment and the parts of the plant?

a hormone is a signaling molecule prodcued in low concentrations in one part of the body and transported to other parts, it binds to specific receptors and triggers responses in target cells and tissues

another name for plant hormones

plant growth regulators

auxin

stimulates cell elongation and cell division; regulates branching and organ bending

gibberellins

promote stem elongation; help seeds break dormancy and use stored reserves

where is auxin found?

apical meristem and other young parts of the plant

what is phototropism?

growth in response to light, stems/shoots= positive phototropism, roots= negative phototropism

how does light affect auxin?

light does not increase or decrease production of auxin, it just determines where its distributed, movement of auxin away fromt he lighted side- cell elongations occurs on the shaded side, making it bend toward the light

Gibberellins- Produced by all plants

stimulates stem elongation, break dormacy in germinating seeds, stimulates early flowering in biennials, stimulates flowering and fruiting many plants

difference in auxin and gibberellins

gibberellins have a general effect, unlike auxin. gibberellins move freely in plants, auxin only move one way.

gibberellins- produced by fungal plant parasites

found in fungi that are parasitic on simple plants (rice), causing "foolish seeding" disease

affects of gibberellins produced by fungi parasite

seedling grows tall and no support, fungus releases gibberellin and stimulates host growth

features of fungi

multicellular (usually), heterotrophs, absorb nutrients

ecological roles of fungi

decomposers, parasitic, mutualistic

decomposers

break down and absorb nutrients from nonliving organic material

parasitic

absorb nutrients from living host

mutualistic

absorb nutrients from hosts and reciprocate with actions that benefit the host

yeast

single cell fungi, inhabit moist environments with plentiful soluble nutrients

hyphae

tiny filaments that make up the fungal body, cell walls contain chitin

purpose of chitin in fungal cell walls

chitin-rich walls are strong and keep cells from bursting from too much water pressure

what are the two types of hyphae

septate and coenocytic

septa hyphae

divides hyphae, have pores which organelles can move from cell-to-cell through the pores

coenocytic fungi

lack septa, have hundreds/thousands of nuclei in a continuous cyotplasmic mass (hyphal substance move freely)

mycelium

network of fungal hyphae that infiltrate a food source

function of mycelium

structue of mycelium maximizes surface to volume ratio, making absorbtion very efficient

another name for mutualistic fungi

mycorrhizae

mycorrhizae

have speacialized branching hyphae used to exchange nutrients with their plant hosts

arbuscules

specialized hyphae that penetrate plant cell walls, but not the cell membrane

mycorrhizae relationship with plants

mycorrhizae fungi deliver soil nutrients to plants, plants supply organic nutrients to the fungi

what kind of plants depend on myycorrhizae

most vascular

spores

used to carry out asexual and sexual reproduction in fungi

spore and nuclei, haploid or diploid?

usually haploid (n)

sexual reproduction in fungi

is not common and requires the fusion of hyphae from different mating types

pheromones

sexual signaling molecules used to communicate their mating type

phases of sexual reprodcution in fungi

plasmogamy, karyogamy, and meiosis

plasmogamy

fusion of protoplasm from two parent mycelia

karyogamy

fusion of nuclei (usually delayed)

meiosis in fungi

reductional nuclear division

what stage do protoplasms from 2 different mycelia fuse?

plasmogamy

the stage in which the fusion of haploid parent nuclei is delayed

karyogamy

T or F, After karyogamy the cell becomes a diploid zygote

true

outcome of karyogamy and meiosis

genetic variation

reproduction of yeasts

produce asexually without producing spores, occurs through simple cell division or pinching of small "bud cells" off a parent cell

chytrids

phylum chytridiomycota, include decomposers, parasites, and mutualists, partially responsible for global amphibian decline

ascomycetes

phylum ascomycota, vary in size and complexity- from unicellular yeast to complex cup fungi and morels

saclike structure where spores are produced in ascomycetes

asci

fruiting bodies produced by ascomycetes during the sexual stage

ascocarps (cups)

what fungi group includes pathogens, decomposers, and symbionts?

ascomycetes

more than 25% of all ascomycetes form ____ . Some form ____ with plants.

lichens and mycorrhizae

basidiomycetes

most well known group of fungi, species including mushrooms, puffballs, and shelf fungi, some are mutualists that form mycorrhizae others are parasites (rusts and smuts), best at decomposition of wood

what is the basidia

cells in which the sexual spores are produced

common name of basidiomycetes

club fungus (becasue of club like shape of basidia)

examples of mutualistic relantionships with fungi

plants, algae, cyanobacteria, and animals

lichens

symbiotic associations between photosynthetic microorganisms and fungi

general characteristics of animals

nutrition mode, cell structure/specialization, reproduction, development, orgin of multicellular animals, and characterization of body plans

characteristics of body plans

symmetry, tissues, body cavities, and developmental patterns

animals are ___ ____.

multicellular heterotrophs

because plants have no cell wall, what assists in support?

structural protein collagen

T or F, animals are the only organisms that have neve and muscle cells

true

how do animals reproduce? and what phase is dominant in the life cyle

sexually, diploid

the life cycle of most animals include a

___ stage

larval

larva

sexually immature form of an animal that is morphologically distinct from the adult, eats different food, may have a different habitat, and undergoes metamorphosis

homeoboxes

sets of DNA sequences (in eukaryotes) that are important in embryonic development and that regulate the expression of other genes

Hox genes

subset of homeobox genes, most animals share

___ ___ are very important in the development of embryonic animals, controlling other genes that influence morphology, especially in segementation and development of appendages

Hox genes

homeobox genes

regulate morphogenesis

hox genes

regulate body segmentation and development of appendages

the origin of multicellularity requires the evolution of what?

new ways for cells to adhere/attach and signal/communicate to each other

body plan

a set of morphological and developmental traits

radial symmetry

symmetry about a central axis, no right/left sides, have anterior/posterior sides

bilateral symmetry

have a dorsal (top) side and a ventral (bottom) side, a right/left side, head/tail end, and sensory equipment (brain)

advantages of radial symmetry

animals meet their environment equally from all sides

advantages of bilateral symmetry

animals can typically move actively from place to place with sensory equipment at the head

sponges have how many tissues?

none

ectoderm

the germ layer covering the embryo's surface

endoderm

innermost germ layer and lines the developing digestive tube, called the archenteron

animals that have only ectoderm and endoderm

diploblastic, include cnidarians

animals with ectoderm and endoderm, and also an intermediate tissues layer called the mesoderm

triploblastic

all bilaterally symmetrical animals are _________

triploblastic

body cavity

space between digestive tract and outer body wall

coelom

body cavity derived from and surrounded by mesoderm, ex earthworms

hemocoel

body cavity formed between the mesoderm and endoderm, filled with hemolymph

hemolymph

a fluid that transports nutrients and waste around the body cavity (open circulatory system), ex roundworms

body cavity for molluscs and arthropods

have both a hemocoel and a coelom, the hemocoel is the primary body cavity and a reduced coelom surrounds the heart and reproductive structures

cleavage, 8 cell stage: spiral and determinate

protosome

cleavage, 8 cell stage: radial and indeterminate

deuterosome

mouth developd from blastopore

protosome

anus develops from blastopore

deuterostome

protosomes, lophotrochozoa

include phylum platyhelminthes, phylum mollusca, phylum annelida

protosomes, ecdysozoa

phylum nematoda, phylum arthopoda

deuterostomia

phylum echinodermata, phylum chordata