Chapter 3.1 Prokaryotes Flashcards
What’s the common name of the phyla of extant plants that’s the more successful
flowering plants
what are the two types of alternation of generations and are they
Gametophyte
- multicellular haploid form
- produces gametes by mitosis
Sporophyte
- multicellular diploid form
- produces spores by meiosis
what are bryophytes and their principal characteristics
mosses and relatives
- no vascular tissues
- no roots or true leaves (rhizoids)
- seedless
- need water for fertilization
- gametophyte dominant
what type of plants dominate landscapes
vascular plants
how does vascular tissue benefit the plants
let plants grow taller
what are the two different kinds of vascular tissue and their characteristics
Xylem
- transports water and minerals upwards
- lignified (contain lignin(extra structural support that makes them stand up))
- composed of tracheids + dead cells
Phloem
- transport products of photosynthesis from leaves to rest of plant
- composed of living cells
what are the benefits of roots or root-like structures
- to absorb water and nutrients from soil
- to anchor the plant (the deeper the roots, the taller it can grow)
what’s the usefulness of being tall for a plant
- more exposure to sunlight
- spores and seeds can disperse farther (so that offspring and parents don’t compete or shade each other if close)
- less chance to be shaded by another plant
benefits of leaves
- increase surface area for photosynthesis
- waxy cuticle to prevent dehydration (the more water a plant needs to conserve, the thicker the waxy cuticle)
what is the use for stomata (stoma in singular)
- for guard exchange in leaves (co2 in, o2 out)
what are seeds composed of
- embryo + food supply + protective coat
allows them to separate from mother plant, disperse by wind or other means and wait for right conditions to germinate
what would be the benefit of being diploid dominant rather than being haploid dominant
- the diploid has a “backup file” and can replace damaged a component, but the haploid cannot, hence they need to be protected
what are the characteristics of gymnosperms (eg. conifers)
- seeds plants
- seeds not enclosed in chambers
- well known gymnosperms
- have pollen so no need water for fertilization
- have microscopic male and female gametophytes
what are the main characteristics of angiosperms
- seed plants
- seeds develop within ovaries
- seeds originate from flower and mature into fruit
- very successful since they represent 90% of living plant spp.
what are the advantages of fruit
- can be dispersed by wind
- can be dispersed by animals
what are the general characteristics of fungi
- most a multicellular
- heterotrophic (absorb food from environment, does not eat food)
- secrete hydrolytic enzymes into surroundings (break down molecules until small enough to be absorbed)
fungi are decomposers, what does this mean
- they break down and abord nutrients from nonliving organic material
what does pathogenic mean
- can cause/spread diseases
name an example of mutualistic fungi
some thermite have fungi in their gut to help them digest wood
bodies of fungi are made out of a network of filaments, what’s it called?
hyphae
- tubular cell walls surrounding plasma membrane
- cell walls of chitin
what do we call the interwoven mass of hyphae
mycelium
- structure maximizes surface to volume ratio
what are called the crosswalls that divide hyphae into cells and have pores that left ribosomes, mitochondria and nuclei flow through
septa
- some are specialized and let them feed on live animals
what is mycorrhizae
- fungi that has a symbiotic relationships with roots of many plants
why are mycorrhial relationships very important in agriculture and nature, fun the fungi and the plant
- the fungi extends the range of roots and can get more nutrients and water for the plants
- in exchange, the fungi receives photosynthetic products from the plant that it can’t produce
what is order of classification of life
- domain
- kingdom
- phylum
- class
- order
- family
- genus
- species
what are the two branches of living organisms
prokaryotes and eukaryotes
were the first organisms prokaryotes or eukaryotes
3.5 billion years ago , prokaryotes
how do we call spherical prokaryotes
cocci, singular: coccus
how do we call spherical prokaryotes in pairs, chains or clusters
pairs: diplococci
chains: streptococci
in clusters: staphylococci
what do we call rod shaped prokaryotes
bacilli, singular: bacillus
may occur in streptobacilli
how do we call spiral shaped prokaryotes
spirilla
do bacteria have a nucleus
no, they have circular chromosome found in NUCLEOID region
what is the name of the asexual reproduction bacteria does
binary fission
what is the use of endospores
bacteria form these resistant cells to withstand harsh conditions
why do most prokaryotes have cell walls
- to maintain shape
- to protect cell
- to prevent bursting in hypotonic environment
what are the cell walls of bacteria composed of
peptidoglycan
- sugar polymers crossed linked by short peptides
what are the cell walls of archea made of
polysaccharides and proteins
differentiate phototrophs, chemotrophs, autotrophs and heterotrophs
Energy source
- phototrophs get from sun
- chemotrophs get from chemicals (us)
Carbon source
- autotrophs get in form of CO2
- heterotrophs get it from organic sources (us)
what is the purpose of heterocysts in nitrogen based metabolism
- specialized cells that fix nitrogen
- have thicker cell walls to prevent oxygen from entering
is the kingdom of protists in prokaryotes or eukaryotes
eukaryotes
what are the forms of nutrition protists are
- photoautotrophs
- heterotrophs
protists can have sexual reproduction
true, asexual and sexual
where can we find protists
anywhere there is water
what are the different groups of protists based on how they get nutrients
- animal-like
- obtain food by phagocytosis
- inhibit fresh h2o
- eg. amoebas - plant-like
- photosynthetic
- multi cellular - fungal-like
- absorptive heterotrophs
- acquire nutrients as decomposers or parasites
what are the evidences that land plants share a most recent common ancestor with green algae
- both have circular rings of cellulose synthesizing proteins in plasma membrane that make microfibrils
- both have similarities in structure of flagellated sperm
- both have evidence of formation of phragmoplast (group of microtubules dividing cell;cell plate then develops in middle
what are advantages to dry land
- sunlight unfiltered by water
- more co2 in atmosphere
- soil near water’s edge rich in nutrients
- initially few herbivores and pathogens
what are the challenges to land life
- scarcity of water
- no structural support against gravity
