Cnidaria Flashcards
1
Q
Form
A
Polyp and medusa forms
* Many are dimorphic
2
Q
Respiration/excretion
A
Diffusion
3
Q
Sensory neurons
A
Detect light/smell/touch
4
Q
Intermediate neurons
A
Connect sensory & motor neurons
5
Q
Motor neurons
A
Control muscles
6
Q
Rhopalia
A
Nerve endings used for balance and light perception
7
Q
Circulation
A
No heart or circulatory system
8
Q
Nutrition
A
- Mouth opens into gastrovascular cavity
- Intracellular & extracellular digestion
9
Q
Reproduction
A
- Polyp: asexually or sexually
- Medusa: Sexually
- Larvae: Free-swimming planula larvae
10
Q
Reproduction process
A
- Sperm fertilizes egg in gastric pouch
- Zygote develops on arms of female
- planula larvae attach and become scyphistoma (polyp)
- polyp can bud to form other polyps
- Polyps become strobili
- Strobili releases saucer-like buds called ephyrae
- ephyrae grow into jellyfish
11
Q
Stages of life
A
- Planula larvae
- scyphistoma (polyp)
- Strobili
- Ephyrae
- Medusa
12
Q
Locomotion
A
- Polyp: Sessile/sedentary
- Medusa: Free-swimming/floating
13
Q
Cnidocytes
A
- Cnida: Stinging organelle
- Nematocyte: Type of cnida
- Cnidocil: Modified cilium that triggers the nematocyte to fire
14
Q
Classes
A
- Hydrozoa
- Scyphozoa
- Cubozoa
- Anthozoa
15
Q
Hydrozoa
A
- Asexual polyp & sexual medusa
- No medusa in freshwater hydra
