week 9c/10a messed up Flashcards
(44 cards)
9 major plant phyla and their significance
- hepatophyta (liverworts)
- bryophyta (mosses)
- anthocerophyta (hornworts)
- lycophyta (lycophytes)
- pteridophyta (ferns and allies)
- cycadophyta (cycads)
- ginkgophyta (conifers)
- anthophyta (angiosperms)
what type of life cycle is found in algae and how is it different in plants
algae = haploid-dominant zygotic life cycle = meiosis occurs right after fertilization
plants = sporic = alternation of generations life cycle with both haploid and diploid multicellular stages
what is alternation of generations in plants
life cycle that alternates beteween a multicellular haploid gametphyte (produces gametes) and a multicellular diploid sporophyte (produces spores)
how did plant dominance shift evolutionarily
evolution moved from gametophyte-dominant to sporophyte-dominant generations
what is endosporous development and why important
heterosporous plants = gametophytes develop inside spore wall, offering protection
do seed plants still use spores
yes. spores still produces. seeds add protection and nourishment to the embryo
how did pollination differ from fertilization
poll=transfer of pollen to the female part of the plant
fert= fusion of sperm/egg
poll happens before fert and doesn’t need water in gymnosperms and angiosperms
what is double fertilization and why unique to angiosperms
1 sperm fertilizes egg (forms zygote), other fuses with 2 nuclei to form triploid endosperm, which nourishes the embryo
what are the defining characterstics of animals
- multicellular eukaryotes
- lack cell walls
- heterotrophic
- motile at some life stage
- reproduce sexually or asexually
who is the closest living relative of animals and why
choanoflagellates = single celled protists that resemble sponge cells (choanocytes)
what key evolutionary innovations define early animal lineages
- tissue development
- symmetry
- body cavities
- embryonic development
- segmentation
what’s the difference between diploblastic and triploblastic animals
dip = 2 layers - ectoderm, endoderm
trip = 3 layers - includes mesoderm
what does it mean to be a coelomate
animal has true body cavity fully lined with mesoderm - important for organ development and movement
what are 4 key innovations shared by all chordates
- notochord - flexible support rod
- dorsal hollow nerve cord - becomes brain/spinal cord
- pharyngeal slits - gill structures or throat components
- post-anal tail - extension of the body beyond the anus
what are cyclostomes and what makes them unique
jawless vertebrates like lampreys and hagfish. they lack jaws and paired appendages but have a skull and notochord
what traits distinguish Chondrichthyes (sharks, rays)
- cartilaginous skeleton
- no swim bladder
- teeth not fused to jaw
- internal fertilization
- well-developed fins
how do actinopterygii differ from sarcopterygii
actinopterygii = ray finned fish, fins supported by rays, muscles inside body
sarcopterygii = lobe finned fish with fleshy fins containing bones and muscles = precursor to tetrapod limbs
why is sarcopterygii important for understanding land vertebrate
their limb-like fins )eg. in coelacanths and lungfish) evolved into the limbs of amphibians, reptiles, birds and mammals
what adaptations allowed vertebrates to live on land
- amniotic egg = prevents desiccation
- thicker skin = reduces water loss
- thoracic breathing = more efficient lung use
- water conserving kidneys
- internal fertilization
what are the main features of mammals
- mammary glands
- hair
- specialized teeth
- enlarged skull and brain
- external ears
- 4 chamber heart
- endothermy
why are birds classified as reptiles
birds evolved from reptiles and share features like
- amniotic egg
- scales
- skeletal structure
- molecular and fossil evidence confirms birds are a lineage with the reptilian aclade
what do all animal cells do
- take in nutrients
- use energy
- make molecules
- respond to signals
- reproduce
how do animals start life
from a fertilized egg that divides into special cells
how is the animal body organized
cells - tissues - organs - organ systems
