Test 1 Flashcards
Chorde
String
notos
back
oura
tail
Kephale
Head
Broad divisions among metazoans based on ______________
number of germ layers
how many germ layers are there
3: Ectoderm. Endoderm, Mesoderm
Ectoderm
superficial skin, lining of most anterior & most posterior digestive tract, nervous system
Endoderm
rest of the digestive system lining, gut lining ,respiratory surfaces, taste buds, thyroid, parathyroid, thymus
Mesoderm
(everything else) muscles, skeleton, connective tissue, circulatory & urogenital system
Deuterostomes have at least ___ differences
3
Radial Cleavage
cleavage planes occur perpendicular or parallel to each other
Spiral Cleavage
cleavage planes occur at oblique angles
Indeterminate cleavage
cells may develop into whole organism if separated
Determinate cleavage
cells lose capacity to develop into a
complete embryo if separated
Protostomia vs Deuterstomia
Deuterostomes have
1. Radial cleavage
2. Indeterminate cleavage
3. The blastopore is at the posterior, and becomes the anus rather than the mouth
Chordate characteristics include:
- A notochord (stiffening rod, not compressible but flexible from side to side)
- A dorsal, hollow nerve cord
- A post-anal tail
- An endostyle (or thyroid gland)
cordata subphyla
- Cephalochordates (Lancelets)
- Urochordata (Tunicates)
- Vertebrata
Amphioxus: Vertebrate-like features
– Notochord under hollow dorsal nerve chord
– Complete gut & post-anal tail.
– Perforated pharynx, endostyle
– Segmentation (myomeres)
Amphioxus: Vertebrate-like features NOT FOUND
- No cranium
– No special sense organs and associated brain
– No kidneys
– No heart
Life is energetically _______ for
vertebrates
Expensive
Subphylum Vertebrata-
Characteristics
- Spinal cord
-serially arranged vertebrae that make up the spinal column - Cranium
-bony cartilaginous or fibrous
-surrounds the brain (cephalization) - Head, sense organs and brains
-prominent
-contains sense organs
-tripart brain: forebrain (olfaction), midbrain (vision), hindbrain (hearing and balance) - Complex endocrine organs
-produce to regulate hormones - Muscularized gut tube
-efficient processing of large amounts of food - Multi-chambered heart
-distribute nutrients and respiratory gases - Mineralized tissues
-(calcium mainly) in tissues to create rigidity - Gills (derived from the endoderm)
there are ____ principle types of tissue
4:
1. Epithelial
2. Muscular
3. Neural
4. Connective
Epithelial Tissue
-protect internal environment
-regulate exchange of material
-consist of one or more layers of cells connected to each other AND to a basal lamina
Muscular Tissue
Contain filamentous proteins actin and
myosin which cause contractions and exert force