• Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off
Reading...
Front

Card Range To Study

through

image

Play button

image

Play button

image

Progress

1/18

Click to flip

Use LEFT and RIGHT arrow keys to navigate between flashcards;

Use UP and DOWN arrow keys to flip the card;

H to show hint;

A reads text to speech;

18 Cards in this Set

  • Front
  • Back
Describe the body plan for Nematoda
Triploblastic, bilateral symmetry, ecdysozoan protostome, pseudocoelomate, cephalization present

other characteristics: are EUTELY, have a set number of cells.
Describe the body plan for MOLLUSCA
Triploblastic, bilateral symmetry, lophotrophozoan protostome, eucoelomate
Describe the body plan for ANNELIDA
Triploblastic, bilateral symmetry, Lophotrophozoan protostomes, eucoelomate, cephalization, segmentation (metamerism)
Describe the body plan for ARTHROPODA
Organ system grade of organization, triploblastic, bilateral symmetry, ecdysozoan protostomes, complete gut, eucoelomate, segmentation, jointed appendages
Why are nematodes referred to as “roundworms”?
cylindrical shape; round in cross section
What is the cuticle? How does the cuticle differ between nematodes, annelids and arthropods?
cuticle is a nonliving external layer secreted by the epidermis. it is molted via ECDYSIS so the body can increase is size. nematodes: cuticle contains high cuticle is a nonliving external layer secreted by the epidermis. It is molted via ECDYSIS so the body can increase is size. Cuticle contains high hydrostatic pressure in nematodes and is secreted by hypodermis. Annelid cuticle is thin, secreted by epithelium, and does not molt. Arthropods have an exoskeleton=hardened cuticle made of two layers (epicuticle and procuticle), is stiffened by chitin, provides surface for muscle attachment, is thin between segments and sheds (ecdysis)
How does the nervous system differ between flatworms, nematodes, annelids and arthropods?
Platyhelminthes: CNS forms nerve ladder; bilobed head ganglion, two ventral nerve cords with cross-strands connecting them.
Nematoda: CNS forms a ring of nerve tissue and ganglia around the pharynx; these give rise to two nerve cords (dorsal and ventral).
Annelida: CNS forms ring around esophagus; ventral nerve cord with nerves in each segment, two cerebral ganglia (brain)
Arthropods: CNS forms ring around esophagus to a double nerve chain of ventral ganglia, dorsal brain
describe Nematodes locomotion. What can earthworms do with regard to locomotion that nematodes can’t do?
Nematodes move in thrashing motion. Earthworms can alternate contractions of longitudinal and circular muscles, which causes a wave of contraction passes from anterior to posterior. This allows them to move forward.
Which phyla consist primarily of members that are monoecious? Dioecious?
Cnidaria, nematodes, molluscs and arthrpods are mostly dioecious.
Platyhelminthes are monoecious.
For annelida, polychaetes are mostly dioecious, oligochaetes and hirudinida are mostly monoecious
what are the two groups of protostomes? What do they have in common? How do they differ? name which group each phyla we've learned belongs to.
-Protostome features: Blastopore becomes mouth, anus forms secondarily; mosaic development; if coelom is present, it develops via schizocoely; some acoelomate, some pseudocoelomate, some eucoelomate
-Lophotrophozoa features: Spiral cleavage; have either lophophore (horseshoe-shaped feeding structure) or trochophore (a larval form)
Lophotrophozoans=flatworms, annelids, molluscs
-Ecdysozoan features: Molt their cuticle (ecdysis) as they grow; do not have spiral cleavage
Ecdysozoans=nematodes, arthropods
Describe three important characteristics that are unique to molluscs
Body is divided in two portions:
-head: has special sensory organs and mouth (with RADULA)
-foot: (usually ventral and secretes mucus) functions is attachment to substrate, locomotion, or both
-visceral mass: contains organs for digestion, circulation, respiration and reproduction; mantle—forms mantle cavity, secretes shell, function in gas exchange
What is a hydrostatic skeleton? Which of the phyla that we’ve studied rely on a hydrostatic skeleton for locomotion or support
A hydrostatic skeleton consists of a fluid-filled closed cavity (e.g., coelom) that muscles contract against which generates internal pressure. Works best when there are pairs of antagonistic (work against each other) pairs of muscles.
Nematodes and annelids rely on hydrostatic skeleton.
Describe the role of the hydrostatic skeleton in earthworms.
fluid-filled coelom serves as a hydrostatic skeleton
-Contraction of longitudinal muscles causes body to SHORTEN and EXPAND
-Contraction of circular muscles causes body to NARROW and LENGTHEN
What is the significance of segmentation in annelids? In arthropods?
In annelids, the entire body is divided into segments, each segment containing similar components of all major organ systems. In Arthropods, segmentation is seen in the appendages which were identical in origin but have been specialized to perform different functions
Describe the process of molting in crustaceans. Why is molting necessary?
Molting (physiological process of making a larger cuticle) and ecdysis (shedding cuticle) are necessary for the body to increase in size because the exoskeleton does not grow as the animal grows. Molting animals grow during the intermolt phases (tissues increase in size until there is no free space left inside the cuticle). During the premolt stage, the cuticle separates from the epidermis. Epidermal cells secrete a new epicuticle, then a new exocuticle. During the next stage (ecdysis) the animal swallows a lot of water which increases its internal pressure and causes the exoskeleton to split. Then animal then crawls out of the old exoskeleton and enters postecdysis (new soft cuticle is stretched and hardens)
What is meant by the term “tagmata? What is the significance of tagmata to arthropods?
Segments tend to fuse/combine into specialized groups called tagmata. Chelicerates and crustaceans have two tagmata (cephalothorax and abdomen), insects have 3 tagmata (head, thorax, abdomen)
What is serial homology and how does it apply to crustaceans?
Homologous structures: structures that share a similar basic plan and have descended from a common ancestor; may or may not have same functions. In crustaceans, walking legs, mouthparts, chelipeds and swimmerets all developed from a common biramous appendage, which makes them homologous to each other. Crustaceans have very many distinct but serially homologous types of appendages.
What are the major features of arthropods that have contributed to their tremendous success in terms of diversity? Explain.
1.Exoskeleton: highly protective
2.segmentation and jointed appendages: more efficient locomotion
-appendages are often specialized for division of labor (food handling, sensing, walking)
3.Tracheal system: air piped directly to cells
-terrestrial arthros use efficient tracheal system for oxygen transport
-aquatic arthros respire via various forms of gills
4.Highly developed sensory organs
-compound eye and other structures for touch, smell, hearing, balancing, and chemical reception
5.Complex behavior patterns
-arthros surpass other inverts in complex/organized activites
-most behavior is innate (unlearned), but some is learned
6.Metamorphosis
-larval and adults have different habitats which avoids competition within a species