Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
chapter 7 mar bio
| Question | Answer |
|---|---|
| Animals without a backbone are known as | invertebrates. Those with a backbone are called vertebrates |
| About 97% of animals are | invertebrates |
| General characteristics of animals | -Multicellular, diploid with tissues, organ systems in most -Heterotrophic -Require oxygen for aerobic respiration -Reproduce sexually, or asexually, or both -Most are motile at some point |
| Radial symmetry | round; equal parts radiate out from a central point (like that seen in a sea star) |
| Bilateral symmetry | organism can be divided into right and left halves that are more or less equal (ex: marine mammals) |
| Porifera | The Sponges -All sessile -filter feeders -Water flow is also essential to carry metabolites (waste) away from cells and to carry gametes. |
| Characteristics of Spoges | -Asymmetric body with no true tissues or organs. -Solitary or colonial -Regeneration capability |
| Sponge cells: Choanocytes (collar cells) | – line interior canals of the body; -flagella on the choanocytes create a water current that brings more food particles into the body -“Collars” on choanocytes traps food particles. |
| Sponge cells: Pinacocytes | - these flattened cells cover exterior of body. |
| Sponge cells: Porocytes | - cells with a pore to allow water to pass into body |
| Sponge cells: Archaeocytes | - ameboid cells that perform a number of functions |
| Sponge cells: Spongin | is a support protein |
| Sponge cells: Spicules | are support structures made of silica or calcium carbonate. - These have a variety of shapes from simple rods to star-shaped |
| Asexual budding in sponges | fragmentation of a cluster of cells from original sponge can begin growth in a new area. |
| Sexual reproduction is sponges | -sperm are released into surrounding water (broadcast spawners) to be picked up by a nearby sponge and directed to egg . Most sponges are hermaphroditic (possess male and female reproductive parts). |
| Cnidarians: | Stinging animals -radial symmetry -mostly marine about 10,000 - Two body forms exist (Medusa,Polyp) |
| Medusa | – free floating form which is transported by water currents, mouth with surrounding tentacles are positioned downward (usually) |
| Polyp | – sessile, attached form with mouth and tentacles are positioned upward |
| Cnidarians have 2 tissue layers: | -Epidermis covers body surface -Endodermis (Gastrodermis) lines internal body cavity and is specialized for digestion |
| Characteristics of Cnidarians: | -Cnidocytes (stinging cells) with nematocyst capsules located on tentacles. These are used for protection and feeding -Digestive system is incomplete ( mouth only) -Nerve net throughout body coordinates movements |
| Jellyfish have | statocysts for orientation and some have primitive eyes. |
| Sexual reproduction in cnidarians | -Medusa is normally the sexual stage -egg and sperm are released and fertilized, result in a zygote |
| Cnidarian Zygotes | develop into a swimming larva called a planula Planula “settles” on bottom to form colony Eventually, new medusa are formed by this mature colony |
| Asexual reproduction in cnidarians | - Polyps typically reproduce by transversal division or by budding |
| Class Scyphozoa | - True Jellyfish -Free swimming large medusa dominates life cycle with only a brief polyp stage -They move by rhythmic contractions, but cannot fight against prevailing water currents -Many with powerful stings |
| Class Anthozoa | – Corals, Anemones, Sea Fans/Whips, Sea Pansy -Colonial polyps that normally lack a medusa stage -Stony corals secrete calcium carbonate “skeletons” -All marine |
| Most coral possess symbiotic algae within body tissues called | zooxanthellae |
| Class Hydrozoa | -Mostly polyp forms with reproductive medusa -Fire Coral, Millepora sp. - Freshwater and marine species |
| Physalia is unusual species of hydrozoa with a colony of polyps carried by | a gas-filled float |
| Ctenophores | – also known as comb jellies |
| Characteristics of comb jellies (ctenophores) | -About 100 species, all marine -8 rows of thick cilia that beat continuously -No nematocysts unless they harbor some from eating cnidarians -Long sticky tentacles used to prey -Most species are planktonic -found in warm and cold waters |
| Platyhelmenthes: | Flatworms -Consist of flukes, tapeworms and turbellarians -About 20,000 -some parasitic, othe free living -first brain |
| Other characteristics of Flatworms | -Bilateral -Single opening to digestive cavity -Three distinct tissue layers (triploblastic) |
| Turbellarians (flatworms) | -Mainly free-living carnivores -Eye-spots present to determine light/dark patterns -Most small -Some with striking coloration patterns |
| Flukes (flatworms) | -All parasitic -Have suckers to attach to inside of blood vessels near intestines of host or other tissues -Vertebrates are the host of the adult fluke -Larval stages may be harbored in shellfish or fish |
| Tapeworms (flatworms) | -Parasitic -Hook for attaching to hosts intestines -body made of repeated segments -no digestive system, they get nutrients from host |
| Nemertea (flatworms) | Ribbon Worms -abt. 900 species, mostly marine -prefer shallow,coastal waters -complete digestive system with mouth and anus |
| More about Nemertea | -Proboscis, a long fleshy tube, is used to entangle prey -These marine predators eat other invertebrates such as worms and crustaceans -One species reaches a length of 100 ft. -Ciliated epidermis. -Circulatory system |
| Nematoda: | Round Worms -Bilateral -Digestive systems -Cuticle present to guard against drying -Some species are important decomposers -Some species are parasitic |
| Annelida: | Segmented Worms -abt. 20,000 species -Live in salt,freshwater or moist terrestrial -Well developed nervous system (with brain) -Segmented internally and externally -Closed circulatory system -Bilateral symmetry |
| Setae | these are bristle-like structures that extend from the sides of each segment which help the annelid stay in place |
| Polychaetes (annelids) | -Largest group of annelids -About 10,000 species - Almost all marine -Some build calcareous tubes or tubes of sticky proteins -carnivores of deposit feeders |
| Many polychaetes have a planktonic larval stage called a | trochophore; this type of larvae is also seen in other invertebrate groups |
| Leeches (annelids) | -Most found in freshwater, some in terrestrial environment, few marine -Marine species are parasitic and may prey on invertebrates or fish -Anterior and posterior suckers to hold prey |
| More about leeches | -Dorsoventrally flattened -Segmentation not as distinct as in other annelids -No setae, no parapodia |
| Oligochaetes | - Include Terrestrial earthworms -The marine species are like terrestrial earthworms -deposit feeders -Mainly found in shallow coastal waters -Have fewer setae -No parapodia |
| Siboglinidae (Pogonophora): | Beard worms - about 135 species Lack a digestive system, which is highly uncommon in the animal world |
| More about Beard worms: | They are appear to use tentacles located at the interior end to absorb nutrients directly from the seawater As a group, they are largely restricted to the deep sea Range in size from 4 inches to 7 feet or longer |
| Sipuncula: | Peanut Worms -about 320 species - Deposit feeders |
| More about Peanut worms: | -Their soft unsegmented bodies possess a retractable multi-lobed or tentacled anterior used for feeding -They normally burrow into soft sediments -Sometimes found in corals or in empty shells of other animals |
| Echiurana: | Spoon worms -135 species -Non-retractable spoon-shaped or forked proboscis (feeding structure) -Deposit feeder |
| More about spoon worms: | -Some taxonomists classify them with annelids -Some burrow in soft bottoms -Others live in coral |
Created by:
awahay
Popular Biology sets