Exam 4 Flashcards
tissue
groups similar cells that act as a functional unit
Blastula
- hollow sphere of cells
- water balloon
Gastrula
the cells start making a pooch inside (infolding)
endoderm
inside layer forms lining of digestive tract
ectoderm
outer cell layer forms skin and nervous system not folded
mesoderm
middle cell layer give rise to muscle and most internal organs
Larva
sexually immature individual that look different from the adult animal
metamorphosis
larva undergoes major change in body form and becomes a mature adult
homeotic genes (HOX genes)
- master control genes
- set of genes that decide what other genes get turned on or turned off
Cambrian explosion
few to many kinds of animals
Why did the Cambrian explosion happen?
- increase of atmospheric oxygen
- arrival of homeotic genes
- increasingly complex predator-prey relationships
- all the animal phyla today can be traced back to this period
irregular symmetry
no symmetry
Radial symmetry
animals that can be divided among many planes and still be the same
Bilateral symmetry
- having only two sides
- can be split in half and get a mirror image
- triploblastic animals
Body Plan
- set of morphological and developmental traits
- what it looks like and maybe how it develops
no tissue layers
- no true tissues
- sponges
eumetazoans
Organisms with tissues (at least two layers of tissues)
diploblastic
two layers of tissue; have ectoderm and endoderm (inside and outside)
Triploblastic
three layers of tissue; include mesoderm
coelom
- Body cavity
- fluid filled space between digestive tact and outer body wall
- cushions organs
- allows organs to grow and move independently of body wall
hydrostatic skeleton
soft bodied animals, fluid in the body cavity used to their advantage
- usually for movement
acoelomates
Triploblastic animals that lack a body cavity
Coelomates
- have a true coelom
- true cavities are developed in the mesoderm (embedded in)
Pseudocoelomates
fake cavity are developed next to the mesoderm
Gastrovascular cavity
- has a single opening (mouth/anus)
- digests the food and distributes the nutrients
Complete Gut/complete digestive system/alimentary canal
- has two openings (mouth and anus)
- more efficient because food is broken down in stages
- food goes into the mouth and waste is discarded through the anus
Complete Gut/complete digestive system/alimentary canal
- has two openings (mouth and anus)
- more efficient because food is broken down in stages
- food goes into the mouth and waste is discarded through the anus
Protostome development
blastopore becomes the mouth
deuterostome development
blastopore becomes the anus
blastopore
the opening that forms during gastrulation
Porifera (porous)
- sponges
- irregular symmetry
- no tissue
- maybe gastrovascular cavity
- most are marine (but all aquatic)
- suspension feeders
- sessile
sessile
attached to the ground/bottom
suspension feeders
trap food and filters water out
cnidaria
- radial symmetry
- eumetazoan (diploblastic)
- gastrovascular cavity
- tentacles (jellyfish)
- carnivores
- use tentacles to push prey into mouth
- all aquatic
cnidocytes
stinging cells on the tentacles
polyp
- sessile
- tube with tentacles at the top
- stage that a cnidaria goes through
Medusa
umbrella with tentacles at the bottom
- Stage that a cnidaria goes through
Platyhelminthes
- Flatworms
- simplest bilaterians (bilateral symmetry)
- marine, freshwater, and damp terrestrial environments, and inside other organisms
- triploblastic
- acoelomates
- gastrovascular cavity
- protostome
turbellaria
- Platyhelminthes
- free-living
- carnivores
- freshwater and prey on small animals
Trematodes (flukes)
- Platyhelminthes
- parasitic
- live in embedded tissue
- wide range of hosts switches from environment to host then back to environment
Cestoda (Tapeworms)
- Platyhelminthes
- parasitize the inside of a digestive system of another animals
- absorb nutrients from the host’s intestines
Rotifera
- Bilateral
- Triploblastic
- pseudocoelomate
- complete gut
- protostome
Molluscs (Mollusca)
- bilateral
- eumetazoan
- triploblastic
- coelomates
- complete gut
- protostome
- have a visceral mass, mantle, and radula
Visceral mass
area where their (Mollusca) guts are stored
mantle
layer of tissue that secretes a shell (Mollusca)
Radula
“teeth” that is used to scrape up food (Mollusca)
Gastropods
- slugs and snails
- only terrestrial group
(Mollusca)
Bivalves
- clams, oysters, mussels, scallops
- shell divided into two halves hinged together
- most are sedentary
(Mollusca)
Cephalopods
(Mollusca)
- squids, octopuses, nautiluses
- fast predators
Annelids (Annelida)
- Worms with Segmentation
- broken into repeated segments
- Bilateral
- eumetazoan
- Triploblastic
- coelomate
- complete gut
- protostome
- Closed circulatory system
Closed circulatory system
blood remains enclosed in the vessels throughout the body
Open circulatory system
blood is pumped into vessels in open body cavities
Oligochaeta
Earthworms
- terrestrial annelids
- ingest dirt and extract nutrients
- aerates the soil
Polychaetes
- largest group
- marine annelids
Hirundinea
- leeches
- fresh water annelids
- free living carnivores but some suck blood
- razor like jaws and anesthesia
- can suck up 10x their body weight in blood
Nematodes (Nematoda)
- Bilateral
- eumetazoan
- triploblastic
- pseudocoelomate
- complete gut
- protostome
- Worms without segments and not flattened
- free living or parasitic
arthropods (Arthropoda)
- Bilateral
- triploblastic
- complete gut
- pseudocoelomate
- segmentation
Why are the arthopods so successful?
- segmentation
- makes it easier to develop
- consists of the head, thorax, and abdomen
head
a segment used for sensing and feeling in arthopods
thorax
a segment used for movement in arthopods
- legs and wings would be attached here
abdomen
a segment that houses the guts in arthopods
- it is the “tail”
molting
sheading their (arthopods) exoskeleton
made of proteins and chitin (same with fungi)
chelicerates (fangs)
- arthopod
- horseshoe crab (aquatic)
- arachnids
- spiders, scorpions, etc.
Myriapods (many legged)
- arthopod
- millipedes
- herbivores
- 2 pairs of legs attached to each segment
- centipedes
- carnivores
- one leg attached to each segment
- carnivores
Pancrustaceans
- arthopods
- consists of the crustaceans and insects
crustaceans
- almost all aquatic
- Isopods (only terrestrial)
- crab
- shrimp
- barnacles
hexapods
insects with 6 legs
what does the body of a hexapod consist of?
- head
- thorax
- abdomen
- three sets of legs
- wings (some)
Why are hexapods (insects) so successful?
- body segmentation
- exoskeleton
- jointed appendages
- flight
- waterproof cuticle
- complex life cycle with short generation and large number of offspring
incomplete metamorphosis
- first kind
- going through many different molting to become an adult
- if it had wings then it is an adult (earn them when they molt for the last time)
complete metamorphosis
- very different as a larva
- just eats to get big so when they’re an adult they can reproduce
- not competing with the adults
Pupa
- in-between stage
- their body melts and reforms into the adult stage
Wings in hexapods
- some are shields with the flying wings under
- some pairs are used for flying
Protective coloration in hexapods
coloring that scares off or deceives predators
Echinodermata
- all marine
- bilateral
- triploblastic
- true coelom
- complete gut
- deuterostomes
- ability to regenerate lost arms
- Sea urchins
- herbivores
endoskeleton
hard calcareous plates under a thin layer of skin
Echinodermata
water vascular system
- that branch into extensions (tube feet)
- moving water from one part of the body
Echinodermata
Chordata
- bilateral
- triploblastic
- true celom
- complete gut
- deuterostomes
What are the two deuterostome phyla?
Chordata and Echinodermata
How is the Chordata phylum defined?
- dorsal hollow nerve cord (along the back)
- notochord
- protects and supports the nerve cord
- under the nerve cord
- pharyngeal slits
- post anal tail (muscular)
Invertebrate cordate
- do not have backbone
- aquatic
cephalochordate
- lancelets
- embedded in marine sand
- all aquatic
Urochordata
- tunicates
- looks like cordate when they are larva (May last only a few minutes)
- class of chordates
Vertebrates
animals that have the sections in their backbone
notochord
- longitudinal, flexible rod
- skeletal support
- hard rod that runs the length of the animal
- kind of only seen during embryonic development
nerve cord (dorsal, hollow)
- Nerve cord that is developed from ectoderm and rolls into tube (like rolled ice cream)
- nerve cord develops into central nervous system (brain and spinal cord)
Pharyngeal slits or clefts
- grooves around the neck area
What is the function of pharyngeal slits
- suspension feeding
- gas exchange (except vertebrates with limbs)
- Develop into part of ear, head, and neck kinda
muscular, post-anal tail
- tail is reduced in a lot of species
- propel aquatic species
Myxini
- cartilaginous skull
- marine
- hagfish
Chepalaspidomorphi/ petromyzontida
feed by clamping their mouth on live fish
- lampreys
Gnathostomes
vertebrates that have jaws
mineralization originated with jaws or bone around mouth
Chondrichthyes
- have skeleton that is made of cartilage
- oily liver to maintain buoyancy
- aerobic cellular metabolism
- constant moving
- class of Chordates
derived characteristics of vertebrates
- Craniates (elaborate skull)
- vertebrae enclosing a spinal cord
- gnathostomes
Osteichthyes
- bony exoskeleton reinforced with calcium phosphate
- bony fishes and tetrapods
Actinopterygii
- ray-finned fishes
- operculum
- swim bladder
- oviparous
Swim Bladder
separate organ that helps them maintain buoyancy (instead of oil they (Actinopterygii) use gasses)
oviparous
eggs but kept inside body
Coelacanths
thought they were extinct but they weren’t
- lobe finned fish
lungfishes
lobe finned fish
tetrapods
- lobe finned fish
- gnathostomes
- four limbs
- a neck
- fusion of pelvic girdle to the backbone
- absence of gills
- ears
Amphibians
- have to have water for reproduction
- larva aquatic
- terrestrial adult
- most have moist skin
Urodela
- salamanders
- amphibians with tails
- half in water half on land
Anura
- frogs
- lack tails
- have powerful hind legs
- frogs with leathery skin are called toads
Apoda
- legless nearly blind
- amphibians without legs
- kinda looks like a weird earthworm snake thing
- salamander that has lost its legs
Amniotes
group of tetrapods
- have amniotic egg
Amniotic egg
- allows tetrapods to reproduce out of water
- adaptation to life on land
- some have shells (talking about the egg)
layers of the amniotic egg
- amnion
- chorion
- yolk sac
- allantois
Reptiles
- most reptiles are ectothermic
- brids are endothermic
- lizards, snakes, birds, dinos
ectothermic
- absorbs external heat as the main source of body heat
- does not maintain body heat through metabolism
endothermic
maintains body temperature through metabolism
Lepidosaurs
- lizard-like reptiles
- tuataras
squamates
- lizards and snakes
- lineage of Lepidosaurs
- snakes are legless lizards
Birds
- Biologically reptiles (dinosaurs)
- Taxonomically they are in class Aves
-flight is very important for them
What is a major adaptation for birds?
wings and keratin feathers
Why is flight so important for birds?
- find things easy
- escape is easy
- flexibility in where to live
What makes Mammals so unique?
- mammary glands
- hair/fur
- high metabolic rate (endothermy)
- larger brain
- differentiated teeth
monotremes
- egg laying mammals
- echidnas and platypus
marsupials
- pouched mammals
- embryo develops within a placenta in the mom’s uterus
- baby is born very early in its development
- finishes development inside the pouch
- convergent evolutions has resulted in marsupials that look like eutherians in other parts of the world
eutherians
- (can be called placental mammals)
- have a complex/more developed placenta
- babies is born very developed
- 1/3 are rodents 1/3 are bats 1/3 is other
arboreal adaptations
tree living adaptations
Primate adaptations
- shoulder and hip joints have wider range of motion
- helps with climbing and brachiation
- grasping hands and feet
- sensitive hands and feet
- short snout and forward pointing eyes
- helps with depth perception
brachiation
Swinging from branch to branch
Lemurs, Lorises, pottos
- lemurs only live in Madagascar
- lorises and pottos only in in Africa and Asia
- group of primates
Tarsiers
- nocturnal
- only found in south east Asia
- group of primates
Anthropoid
monkeys and apes (hominoids)
hominoids
- monkeys and apes
- have larger brains relatively
- rely on eyesight and less on olfaction than other mammals
- fully opposable thumbs
characteristics all monkeys have
- diurnal
- live in social groups
- have forelimbs about equal in length to hind limbs
New World Monkeys (Central and South America)
- all arboreal
- prehensile tail: adapted for grasping limbs
- nostrils are wide apart and wide open
Old World Monkeys (Africa and Asia)
- some are arboreal but some are found on the ground
- tail can’t really support the monkey’s weight might be used for balance
- nostrils close together and point down
Apes (Family: Hominidae)
- Gibbons, orangutans, gorillas, chimpanzees, and humans
- nonhuman apes only in Africa and southeast Asia in tropical rain forests
- larger brain size relatively and flexible behavior
- most apes are vegetarian however they are opportunistically omnivores
Gibbons
- fully arboreal apes
- monogamous
- smallest, lighter, most acrobatic
Orangutans
- orange ones
- solitary ape (shy)
- only in Indonesia
- largest arboreal mammal
Gorillas
- Largest ape
- fully Terrestrial
- knuckle walkers
Chimpanzees
- 75% in trees 25% on ground
- tropical Africa
- makes and uses tools
- share 99% of genes with humans
Paleoanthropology
study of human origins and evolution
How are humans different?
- Humans are bipetal
- we walk on two legs all the time (upright)
- Humans have the largest relative brain size
- reduced jawbones and jaw muscles
- shorter digestive tract
Homo neanderthalensis
- went extinct
- brains the same size as ours
Deuterostomia
echinoderms (sea stars and
relatives), and chordates
This clade includes both vertebrates and invertebrates
Ecdysozoa
a clade of invertebrates that shed their
exoskeletons through a process called ecdysis
Lophotrochozoa
clade of bilaterian
invertebrates
lophophore
feeding structure in lophotrochozoans
trochophore larva
distinct developmental stage in lophotrochozoans
