Bio 11 Flashcards
What are three different animal characteristics?
- Eukaryotic
- Heterotrophic by ingestion
- Multicellular with a high degree of cell specialization
What is radial symmetry
You can divide it a lot of times through its centeral axis and it will be the same
Organisms with radial symetery have a ___ shaped body with no ___
- Cylindrical
- Head, front or back
What is bilateral symmetry
You can only cut it into two equal halves, through the mid dorsal line (spine)
What does bilateral symmetry allow for?
Cephalization (Organs and everything being concentrated in torso resulting in an enlarged head)
What are germ layers
Primary layers created during embryo development that from the various tissues and organs
What are the three germ layers
Endoderm, mesoderm, and ectoderm
What does it mean when an animal has no germ layers
It means they are the most primitive with no organs or tissues
What does it mean when an organism is diploblastic
It means it has two germ layers, ectoderm and endoderm
What does the ectoderm make?
(Outer layer) Skin and nervous system
What does the endoderm make
(Inner layer) The endoderm makes the lining of the digestive track
What does it mean when an organism is triploblastic?
It means that it has all three germ layers
What does a mesoderm create?
The mesoderm creates most of the remaining internal organs and muscles
What is a body plan
The type of body cavity that an organism has
The evolution of a body cavity that provides a place for organs and organ systems to grow is called what?
Coelom
Acoelomates
No coelom and poorly developed organs
Pseudocoelomates
Pseudocoelomates have a body cavity between the endoderm and mesoderm layers, however there is no muscle around the gut and no co-ordination of food through their digestive tract. Only some organs develop through this space.
Example of a pseudocoelomate
Tardigrade, roundworms
Coelomates
Coelomates have a body cavity between the mesoderm of the body wall and around the gut, they have co-ordinated digestion and development of major organs
Example of a coelomate
Earthworm
What does segmentaion lead to
Specialized body regions
Non segmented organisms have ___ segments
No specialized
Example of non-segmented organisms
Flatworm
Segmented organisms have what?
Identical repeating sections
Example of segmented organisms
Earthworms
Segmented organisms with specialization
Where an organisms body segments fuse together to become body regions which focus on one set of tasks (spiders)
Lower invertebrates have what?
Have simple biology
What do the lower invertebrates include?
- Porifera
- Cnidaria
- Platyhelminthes
- Nematodes
Higher invertebrates - Protostomes are
- One of the two main branches of evolution
- Named this way due to embryo development
What do higher invertebrate protostomes include?
- Annelids
- Mollusks
- Arthropods
Higher invertebrates - deuterostomes
Animals on the other great branch of animal evolution
What do the higher invertebrate deuterostomes include
- Echinoderms
- Lower chordates
Vertebrates
Represents the most highly evolved animals (US!!)
What does “porifera” mean?
Pore bearers
How long have sponges been around for?
At least 540 million years
Are phylum porifera considered animals? Why or why not?
Yes, because they are multicellular, heterotrophic, and their cells have no cell walls
What do sponges represent?
The first experiment in multicellularity for animals
Sponges are
The most simplest and primitive animals and have changed very little since they evolved
What kind of symmetry do sponges have?
Asymmetrical
What are choanocytes (collar cells)
They are specialized cells that use flagella to move water through the sponge
Where does water exit a sponge?
It exits through the osculum, a large hole at the top
What does the movement of water through a sponge allow for?
- Feeding
- Respiration
- Circulation
- Excretion
What are Archeocytes? (Amoebocytes)
Moving cells that have different functions ranging from nutrition delivery to other cells and the production of eggs for sexual reproduction
What are sponges body plan
A simple skeleton, however harder sponges have more spiny spicules
What’s a spicule?
A spike shaped structure made up of chalklike calcium carbonate or glass-like silica
What is the body plan of softer sponges?
An internal skeleton made up of spongin
What are spongin?
Spongin are a network of felxible protein fibers
Sponges are filter feeders, which means what?
It means they filter food particles from the water using their choanocytes
Describe the process of sponge diffusion
- Oxygen from water diffuses into cells
- Waste products like carbon dioxide and ammonia diffuse out of cells into central cavity and out of osculum
Sponges don’t have a central nervous system that would allow them to respond to their environment, so how do they protect and defend themselves?
Sponges defend themselves by creating toxins that are harmful to potential predators
How do sponges reproduce?
By either asexual or sexual reproduction
How does sexual sponge fertilization work?
Sperm + egg =Zygote - Larva
Sponge larvae are ___and move to a different location
- Motile
How does sponge asexual reproduction work?
A new sponge clone forms on the side and eventually forms a clone
What is a gemmule
gemmule is something that a sponge can grow in unfavorable conditions, which can survive said conditions and then regrow the sponge
What are the four classes in the Cnidaria phylum
- Cubozoa
- Scyphozoa
- Anthozoa
- Hydrozoa
What are Cnidarias
Soft-bodied carnivorous animals that are diploblastic (true tissues)
What is the defining characteristic of Cnidarians?
Their defining characteristics are the fact that they have stinging tentacles around their mouths
What a cnidarians stinging cell called?
A cnidarians stinging cell is called a cnidocyte
What are inside of the cnidocytes
A nemacyst
What is a nemacyst
A poison filled stinging structure that contains a tightly coiled dart
What should you think of a cnidocyte
Think of it as a harpoon gun and the nemacyst as the harpoon
What is the body plan of a cnidarian
Radial symmetry, diploblastic
What are the two main body plans of a cnidarians
Medusa and polyp
Polyps are usually ___?
Sessile
What does sessile mean
Permanently attached or established
Polyps have a ___?
Cylindrical body with arm like tentacles and a mouth that points upwards
How do polyps usually reproduce?
They usually reproduce asexually
How do cnidarians capture and eat their food?
They paralyze their prey into its mouth and then into its gastrovascular cavity. They then digest it outside their cells and then absorb it into their gastroderm. Any undigested materials leave through the same opening.
What is a way that Cnidarians move
By using their hydrostatic skeleton
What is a hydrostatic skeleton
A circular layer of longitudinal muscles that by using the water in the gastrovascular cavity, let the cnidarian move
The movement of a cnidarian allows for what?
The polyps to get taller and medusas to create a jet propulsion
How do cnidarians reproduce?
Sexually and asexually
Does sexual reprodution for cndarians occur internally or externally?
Externally
What happens after a cnidaria larva develops?
It grows into a planula larva
What are the four groups of cnidarias
- Jellyfish
- Hydras
- Sea anemones
- Corals
Where are cnidarias found?
Freshwater and saltwater
What stage is dominant for the class hydrozoa?
The polyp stage
What is used for species dispersal with the class hydrozoa?
The medusa
What is included in the class anthozoa?
Anemones, corals, sea pens
The class Anthozoa generally only has the ___?
Polyp stage
Two things about class Scyphozoa
- Medusa stage is dominant
- Includes the jellies
What is a flatworm
Soft, flattened worms that have tissues and internal organ systems
How many germ layers do flatworms have
Three
What kind of symmetry do flatworms have
Bilateral
Are Platyhelminthes triplobloblastic?
Yes
Are flatworms acoelomates or coelomates?
Acoelomates
What do free-living flatworms internal organ system look like?
- Organs for digestion
- Excretion
- Response
- Reproduction
What do parasitic worms internal organ system look like?
Similar to free-living worms systems
Free-living worms can get food from __?
- Tiny aquatic animals
- Dead animals
Like Cnidarians, flatworms have what?
A digestive cavity with a single opening which both food and waste pass through
What is a pharynx?
A muscular tube that extends out of the mouth and then pumps food into the digestive cavity
What do parasitic worms feed on?
Blood, tissue fluids, or ices of cells within the hosts body
Parasitic organisms do not have a ___?
Complex digestive system
Because flatworms bodies are so ___, many of them do not need a ___nutrients around their bodies
- flat and thin
- circulatory system to transport
What do flatworms rely on to support internal tissues
Diffusion to transport oxygen
What are things that flatworms don’t have?
- Gills or other respiratory organs
- Heart
- Blood or blood vessels
What are flame cells
Specialized cells that filter and remove metabolic wastes like ammonia and excess from flatworms bodies
What makes flatworms different from Cnidarians and sponges
More complete structures that are better at detecting and respnding to stimuli
In free-living flatworms, what does a head enclose?
Several ganglia that control their nervous systems
What is a nerve ladder in a flatworm?
A nerve ladder? They are two long nerve cords running down from the ganglia along both the sides of the body
What do flatworms eyes detect?
Changes in the amount of light in their environment
Flatworms also have cells that do what?
Detect external stimuli like chemical in the water and the direction that the water is flowing in
Parasitic flatworms lack what?
Many traits that regular flatworms have
What are the two ways that flatworms move?
- Cilia on their epidermal cells that help them glide through water and over bottoms of streams and ponds
- Muscles controlled by their nervous systems that let them twist and turn
How do flatworms reproduce?
Sexually and asexually
What does the class turbellaria include?
Planaria
Class trematoda (liver flukes)
Worms that grow through liver and cow manure, travel through mud snail, are eten, rinse ad repeat
Tapeworms
Attaches to the inner wall of the intestine and feeds off of food being digested. Pieces break off along with eggs, travel through fecal matter. It then infects soil or water
What are roundworms
Slender, round, unsegmented worms with tapering ends
What are the two groups of roundworms
- Free living
- Parasitic
How many germ layers do roundworms have?
Three
Where are roundworms body cavities located?
Between the endoderm and mesoderm (pseudocoelom)
What is the body plan of roundworms
- Have a complete digestive tract with a mouth and anus
- ## “Tube within a tube structure”
What do roundworms use to exchange gases and excrete metabolic waste
They use their body walls
Roundworms have no ____ and rely on ___
- Internal transport system
- Diffusion on the movement of nutrients and wastes
Roundworms have muscles that ___?
Extend the length of their bodies
How do roundworms move?
By using a hydrostatic skeleton, they contract these muscles to move like a snake through the water they’re in
How do roundworms reproduce?
Sexually, through internal fertilization
Parasitic roundworms (what do they do)
Cause malnutrition and absorb nutrients from the host, abdominal pain, coughing and gagging. Spread by eating unwashed vegetables
Hookworm (what does it do?)
Enters in between toes and hooks onto the intestine of host, draining its blood
Pinworm
Eggs are spread when people itch anus, female migrates out of anus each night so the eggs can be spread
Trichinella (What do they do?)
Comes from eating undercooked pork, invades muscles and organs and forms painful cysts in them
Filarial worm
Small nematode that lives in lymph nodes and blocks the ducts causing swelling and inflammation in the area (EXTREME)
What are the five ways to classify an animal
- Symmetry
- Germ layers
- Body plan
- Segmentation
- Evolution
Is a Medusa motile or sessile?
Motile
What is alteration of generations?
Jellyfishes ability to reproduce secually and asexually
What ate flame cells primary function?
Excretion
What are platyhelminthes body plan and Germ layers
Bilateral triploblactic
A nematode has what type of Coelomate?
Pseudocoelom
What is a hydrostatic skeleton?
Fluids in a roundworms pseudocoelom and muscles that help it move
What is included in class Hydrozoa
- Hydra
- Portuguese man of war
What animals are included in the class scyphozoa
- Moon jelly
- Purple jelly
What animals are included in the class cubazoa
- Box jelly
