BIOL 211 Exam 2 Review
Supplemental Instruction
Iowa State University / Leader: / Leah C.
Course: / BIOL 211
Instructor: / Dr. Biederman
Date: / 2/7/18
  1. List the characteristics of animals.

Multicellular, heterotrophic, ingestion, no cell walls (held together by collagen), most possess tissues, most reproduce sexually, diploid dominant, gametes produced through meiosis and usually only haploid cells, move under own power at some point, specialized cells, regulate cell growth and cycle, cell adhesion, innate immunity, developmental regulation, programmed cell death

  1. What are the closest relatives to animals?

Choanoflagellates

  1. How can we classify animals? What is this process?

Compare DNA sequences – molecular phylogeny

  1. Compare and contrast sponges and choanoflagellates.

Sponges – first animals in fossil record, multicellular, animals

Choanoflagellates – some are colonial, single-celled, protists

Both – sessile, feed with similar structures

  1. What are tissues? List the three categories of tissues (all animals, then two subcategories).

Colletions of specialized cells isolated from other tissues by membranous layers

Metazoa – all animals; divided into parazoa (no specialized organs/tissues – sponges) and eumetazoa (more than one type of tissues and organs)

  1. Diagram/explain how a normal embryo develops, as well as the different stages the structures are formed at.

Fertilized cell (zygote)  cleavage (repeated)  blastula (hollow ball of cells)  gastrulation (fold in on self)  form gastrula (with germ layers)/blastopore (either mouth/anus)

  1. What are germ layers? What are the two names for the different number of germ layers? List the three that can be formed, and what they develop into.

Layers of cells that give rise to various tissues and organs of the animal body

Animal either diploblastic (two layers) or triploblastic (three layers)

Ectoderm (skin and nervous tissue), endoderm (lines digestive tract and internal organs), mesoderm (muscles and most other organs)

  1. Compare and contrast a neural net and central nervous system.

Both used to send sensory information/respond

Neural net – no organization, slower response time, not efficient

CNS – linear, very fast, efficient

  1. What are the types of symmetry an animal can have? What are characteristics of each?

Radial – same no matter what way cut, experience environment from all sides

bilateral – two halves if cut in half, usually have head, head = direction, have CNS

  1. Draw a picture and list the body cavities organisms can have. What is the purpose of this cavity?

Coelom – fluid-filled space separating the digestive tract from the outer body wall with mesoderm

Coelmate – body cavity completely lined by mesoderm tissue

Pseudocoelomate – body cavity not completely lined by mesoderm tissue

Acoelomate – no body cavity

Cushions organs, prevent injury, act like skeleton, allows organs to move/grow

  1. How do protostome and deuterostomes differ during embryonic development?

Protostome – blastopore forms mouth, cleavage spiral and determinate

Deuterostome – blastopore forms anus, cleavage radial and indeterminate

  1. What is segmentation? Why is this significant?

Allows for specialization –repetition of components = backup and specialization

  1. How do we define animal groups?

Body plan – symmetry, organization of tissues, type of body cavity, pattern of embryonic development

  1. What is the gastrovascular cavity? Explain the difference between an incomplete and complete digestive system.

Digestive system. Incomplete digestive system – only an entrance, undigested material back out through mouth. Complete digestive system – mouth and anus, travels throughout body during digestion

  1. Why are rising temperatures dangerous for aquatic animals, especially sponges? Know how to tell by looking at a graph whether coral bleaching has occurred.

Coral bleaching – spit out cells that generate energy

See activity on Canvas

  1. How can you differentiate between a parasitic flatworm and a free-living flatworm?

Parasitic – all reproductive structures, hooks on mouth/head

Free-living – eye-spots, extensive gastrovascular cavity.

  1. Compare and contrast incomplete and complete metamorphosis.

Complete – babies and parents don’t look alike/live in different environments/eat different food

Incomplete – babies look like mini adults/ live in same environment/eat same food

  1. Sponges

Multicellular with several cell types, asymmetrical, no tissues, mostly marine, adults sessile but larvae are free-swimming, don’t produce gastrula or germ layers, choanocytes, filter-feed, hermaphrodites, release gametes into water but internal fertilization

  1. Cnidarians

Most marine, muscles and nerves, eumatazoans, diploblastic, radial, incomplete gastrovascular cavity that also acts as hydrostatic skeleton, polyp or medusa, cnidocytes (stinging cells), hermaphroditic or male and female, external fertilization, can also sometimes reproduce asexually

  1. Protostomes

Blastopore forms mouth, cleavage – spiral and determinate, triploblastic, cephalization, coelom, CNS

  1. Lophotrochozoans

Bilateral, triploblastic, spiral cleavage, life stage with ciliated feeding, trochophore or lophophore

  1. Platyhelminthes

Lost coelom (acoelomate), no lophophore/trochophore, live in marine, freshwater and terrestrial habitats, many parasitic species, bilateral, cephalization, flattened dorsoventrally, incomplete digestive system, no organs, CNS, pharynx

  1. Turbellarians

Free-living, many marine, extensive gastrovascular cavity

  1. Tematoda

Flukes, parasites, attach with suckers, extensive reproductive organs

  1. Cestoda

Tapeworms, parasites, no digestive system, head with hooks and suckers, extensive reproductive organs

  1. Annelids

Segmented worms, coelom, segmentation

  1. Polychaetes

Mostly marine, parapodia = movement and gas exchange

  1. Oligochaetes

Earthworms, hermaphrodites, release mucus cocoon for reproduction, eggs fertilized in cocoon, produce casts (fertilize), aerate soil

  1. Hirudinea

Leeches, blood-sucking ectoparasites or predators, can be used in medicine

  1. Mollusks

Second largest animal phylum, most marine, but also terrestrial/freshwater species, coelomates, complete digestive system, usually separate sexes but can be hermaphroditic (snails), either open/closed circulatory system, body plan = foot, mantle, shell (external, internal, none), visceral mass, gill, radula (except for bivalves)

  1. Gastropods

Snails and slugs, marine, freshwater, and terrestrial habitats, usually herbivores but can be predators

  1. Bivalves

Marine and freshwater, two shells, usually filter-feed, muscular foot for movement and digging into sediments, no radula, separate sexes, internal fertilization

  1. Cephalopods

Marine, fast predators, most lack or have internal shells, octopus and squid, nautilus has external shell, squids – take water into mantle cavity and expel through excurrent siphon, cephalopods = smart and can learn from each other

  1. Ecdysozoans

Excrete exoskeleton as grows, made of chitin, bilateral, triploblastic, cuticle exoskeleton provides support and protection

  1. Nematodes

Aquatic and terrestrial habitats, also parasites of plants and animals, cuticle made of collagen, pseudocoelomates, complete digestive system, nervous system and cephalization, usually male and females, many free-living decomposers, some parasites,

  1. Arthropods

Largest animal phylum, jointed feet, exoskeleton made of chitin and protein, can be tough or soft and flexible, relatively impermeable to water, segmented body, hard exoskeleton, jointed appendages, and well-developed head and sensory organs, open circulatory system

  1. Chelicerata

Claw-like feeding appendage, most terrestrial, spiders, ticks, scorpions, two main body regions (cephalothorax and abdomen)

  1. Myriapoda
  1. Diplopoda

Many walking legs, 2 pairs per segment, herbivores, produce toxins to discourage predators

  1. Chilipoda

Carnivores, poison claws for prey and defense

  1. Crustaceans

Aquatic and freshwater, crabs, shrimp, barnacles, isopods, copepods, two body cavities (cephalothorax and abdomen), two pairs of antennae, chewing mouthparts, branched appendages, over 5 pairs of legs

  1. Insecta

Most successful group of arthropods, more species than all other groups of animals combined, terrestrial and freshwater, three body regions (head, thorax, abdomen), three pairs of legs, one pair of antennae, many species have one/two pairs of wings, fly, specialized mouth parts, metamorphosis (complete and incomplete)

  1. Hymenoptera – bees/wasps
  1. Orthoptera - grasshoppers
  1. Diptera - flies
  1. Odonata - dragonflies
  1. Lepidoptera - butterflies
  1. Hemiptera – “true bugs,” cicadas
  1. Coleoptera - beetles