BIO 112 Exam Questions and Verified Answers/Accurate Solutions| Already Graded A+
kingdom animilia Multicellularity - not unique to animals but ALL animals
-Nutritional mode - Heterotrophs that digest food internally (compare to
KingdomFungi)...exceptions
-All are heterotrophic and must ingest food to digest it inside a gut (continuous with
outside!)...some notable exceptions- -Fungi all heterotrophic but exhibit external digestion and
absorption
all animals have 1.Gene sequences indicate monophyly through a common ancestor
2.Common set of extracellular matrix molecules(collagen and proteoglycans) replace the cell
wall(absent in animals) 3.Unique junctions between cells (tight junctions, desmosomes, and gap
junctions)
body plan features - symmetry
- body cavities
- segmentation
- presence and function of appendages
animal reproduction - Diploid stage is dominant- Haploid sperm and eggs produced via
meiosis • Most often, small flagellated sperm fertilizes a larger, immobile egg to form diploid
zygote • some switch between sexual/asexual repro. depending on situation • Good for
changing environments to increase likelihood of adaptive combinations of genes
non bilaterlarians • Either asymmetrical (sponges and Placozoan adults) or radially
symmetrical(Ctenophores and Cnidarians)
• No nervous system (sponges and Placozoans) or simple nerve nets(Ctenophores and
Cnidarians)
• Monoblastic (sponges) or diploblastic(Ctenophores, Placozoans, andCnidarians)
Phylum Ctenophora - comb jellies • Sister Clade to all other animals
,- Hox genes and other genes present in other animals absent in comb jellies
• Diploblastic, radially symmetrical
• Complete gut with two openings (mouth and anus)
• Lack muscular tissue - move via cilia- 8 rows of cilia-bearing plates called ctenes
• Tentacles possess sticky material to capture prey
• Sexual reproduction happens outside the body usinggametes ejected out the mouth/anus
Phylum Porifera-sponges • Only phylum to lack true tissues (monoblastic) • Sessile • Most
marine, some freshwater • Suspension feeders • Sequential hermaphrodites - Sperm released
and fertilize different sponge - Zygotes flagellated, free-swimming larvae
Porifera Anatomy • Choanocytes-flagellated cells that create micro current to suck food
particles into finger like projections forming a collar around the cell; engulf food via
phagocytosis • Amoebocytes-majority of cellular structure; use pseudopodia to move
throughout mesohyl(gelatinous matrix layered into sponge "body"
Phylum Cnidaria-hydras, corals,and jellies •Diploblastic, Radial symmetry
•Nerve net without central processing center
-Simple contractile fibers induce movement
•Two growth forms: medusa and polyp
•All carnivorous
•Most have tentacles surrounding digestive opening that trap, subdue, and push prey into
gastrovascular cavity for digestion
•Very simple contractile fibers (muscles) and a non-centralized nerve net
3 Clades of Cnidarians
Anthozoans • Sea anemones and corals • Polyps only, solitary or colonial- Many secrete
hard, calcium carbonate skeleton that build son layers from previous generations • Corals •
Reefs offer habitat to numerous other species- Second in diversity only to tropical rainforests(d)
Anthozoa
, Scyphozoans • Medusa form dominates • Classic "Jellyfish" • Coastal species go through
small polyp stage but open water species lack polyp stage
Hydrozoans • Most alternate between medusa and polyp stage of life cycle - Polyp
conspicuous - Some polyp-only (Hydra) • Most sexual- Dormant zygotes to withstand difficult
environmental conditions(a) Hydrozoa
Protosome characteristics • Most numerous by species and individual count. - Considered
the most successful format of bilateral organisms • Blastopore of gastrula becomes mouth of
the digestive tract. • Anterior brain that surrounds the entrance to the digestive tract • Ventral
nervous system with paired or fused longitudinal cords
Lophotrochozoans Name comes from two structures possessed by a few members
(lophophore and trochophore larvae
Phylum Platyhelminthes-flatworms • Marine, freshwater, and damp terrestrial habitat •
Both free-living and parasitic species • Dorsoventrally flattened- • Acoelomates -lack coelom-
Respiration and nitrogenous waste elimination occur across body surface - Surface area for
exchange is increased via thin body shape. • Materials move around body via diffusion. - No
circulatory system
Free-living Flatworms (Class Turbellaria) • Can reproduce asexually through fission • Most
sexual; hermaphrodites cross-fertilize each other (penis fencing)
• Dugesia, common in clean ponds
- Glide along ventral surface on cilia and mucus and swim via undulating motion
- Light-sensitive eyespots and chemical-detecting lobes atanterior end represent cephalization •
Can learn to modify stimulus-response
Parasitic Platyhelminths •Over half of all flatworms are parasitic
•Suckers to attach to substrates
kingdom animilia Multicellularity - not unique to animals but ALL animals
-Nutritional mode - Heterotrophs that digest food internally (compare to
KingdomFungi)...exceptions
-All are heterotrophic and must ingest food to digest it inside a gut (continuous with
outside!)...some notable exceptions- -Fungi all heterotrophic but exhibit external digestion and
absorption
all animals have 1.Gene sequences indicate monophyly through a common ancestor
2.Common set of extracellular matrix molecules(collagen and proteoglycans) replace the cell
wall(absent in animals) 3.Unique junctions between cells (tight junctions, desmosomes, and gap
junctions)
body plan features - symmetry
- body cavities
- segmentation
- presence and function of appendages
animal reproduction - Diploid stage is dominant- Haploid sperm and eggs produced via
meiosis • Most often, small flagellated sperm fertilizes a larger, immobile egg to form diploid
zygote • some switch between sexual/asexual repro. depending on situation • Good for
changing environments to increase likelihood of adaptive combinations of genes
non bilaterlarians • Either asymmetrical (sponges and Placozoan adults) or radially
symmetrical(Ctenophores and Cnidarians)
• No nervous system (sponges and Placozoans) or simple nerve nets(Ctenophores and
Cnidarians)
• Monoblastic (sponges) or diploblastic(Ctenophores, Placozoans, andCnidarians)
Phylum Ctenophora - comb jellies • Sister Clade to all other animals
,- Hox genes and other genes present in other animals absent in comb jellies
• Diploblastic, radially symmetrical
• Complete gut with two openings (mouth and anus)
• Lack muscular tissue - move via cilia- 8 rows of cilia-bearing plates called ctenes
• Tentacles possess sticky material to capture prey
• Sexual reproduction happens outside the body usinggametes ejected out the mouth/anus
Phylum Porifera-sponges • Only phylum to lack true tissues (monoblastic) • Sessile • Most
marine, some freshwater • Suspension feeders • Sequential hermaphrodites - Sperm released
and fertilize different sponge - Zygotes flagellated, free-swimming larvae
Porifera Anatomy • Choanocytes-flagellated cells that create micro current to suck food
particles into finger like projections forming a collar around the cell; engulf food via
phagocytosis • Amoebocytes-majority of cellular structure; use pseudopodia to move
throughout mesohyl(gelatinous matrix layered into sponge "body"
Phylum Cnidaria-hydras, corals,and jellies •Diploblastic, Radial symmetry
•Nerve net without central processing center
-Simple contractile fibers induce movement
•Two growth forms: medusa and polyp
•All carnivorous
•Most have tentacles surrounding digestive opening that trap, subdue, and push prey into
gastrovascular cavity for digestion
•Very simple contractile fibers (muscles) and a non-centralized nerve net
3 Clades of Cnidarians
Anthozoans • Sea anemones and corals • Polyps only, solitary or colonial- Many secrete
hard, calcium carbonate skeleton that build son layers from previous generations • Corals •
Reefs offer habitat to numerous other species- Second in diversity only to tropical rainforests(d)
Anthozoa
, Scyphozoans • Medusa form dominates • Classic "Jellyfish" • Coastal species go through
small polyp stage but open water species lack polyp stage
Hydrozoans • Most alternate between medusa and polyp stage of life cycle - Polyp
conspicuous - Some polyp-only (Hydra) • Most sexual- Dormant zygotes to withstand difficult
environmental conditions(a) Hydrozoa
Protosome characteristics • Most numerous by species and individual count. - Considered
the most successful format of bilateral organisms • Blastopore of gastrula becomes mouth of
the digestive tract. • Anterior brain that surrounds the entrance to the digestive tract • Ventral
nervous system with paired or fused longitudinal cords
Lophotrochozoans Name comes from two structures possessed by a few members
(lophophore and trochophore larvae
Phylum Platyhelminthes-flatworms • Marine, freshwater, and damp terrestrial habitat •
Both free-living and parasitic species • Dorsoventrally flattened- • Acoelomates -lack coelom-
Respiration and nitrogenous waste elimination occur across body surface - Surface area for
exchange is increased via thin body shape. • Materials move around body via diffusion. - No
circulatory system
Free-living Flatworms (Class Turbellaria) • Can reproduce asexually through fission • Most
sexual; hermaphrodites cross-fertilize each other (penis fencing)
• Dugesia, common in clean ponds
- Glide along ventral surface on cilia and mucus and swim via undulating motion
- Light-sensitive eyespots and chemical-detecting lobes atanterior end represent cephalization •
Can learn to modify stimulus-response
Parasitic Platyhelminths •Over half of all flatworms are parasitic
•Suckers to attach to substrates
