This PowerPoint helps students to consider the concept of infinity.
The general body plans of animals. biology
1. The General Body Plans of Animals Prepared by: Group 1 Morning Joseph Martin Paet Gladys Kim Remolacio Jesebel Garlan Ruby Cocal Jeremy Nacido
2. INTRODUCTION Most animals are bilaterally symmetric, including humans. It could be divided into matching halves by drawing a line down the center. It permits streamlining, favors the formation of a central nerve center, contributes to cephalization, and promotes actively moving organisms.
3. Radially symmetric animals are symmetrical about an axis extending from the center of the oral surface. Radial Symmetry Coral Jelly Fish
5. REGIONS Segmentation the division of some animal body plans into a series of repetitive sections. “Advanced” animals have body segments, and specialization of tissue. Metamerism segments are similar with each other. Tagmatization segments are different and may become fused to fused to a functional groups/tagmata.
6. Terms to be Familiar With Anterior head-end Posterior tail-end Cephalic toward the head Caudal toward the tail Dorsal back side Ventral belly side Lateral on or toward the side Medial on or toward the middle Proximal toward the central part Distal toward the extremities Peripheral near the surface of the body
9. The Roundworm Ascarislumbricoides, a common intestinal roundworm having a bilateral symmetry. It lacks true segmentation and appendages. It is covered with a tough, elastic cuticle, bearing minute striations. Four whitish longitudinal lines extended along the body, one dorsal, one ventral, and two lateral. The mouth opens at the anterior end between three rounded lips. The anus is a transverse slit close to the posterior end of the ventral surface. Figure 7.2
10. The Earthworm The Pheretima has a bilaterally symmetrical body, long and cylindrical, bluntly tapered at each end, and somewhat depressed posteriorly. The body is organized in a linear series of similar segments (somites/metameres) which is called mesmerism. The mouth is in the first somite and the vertically oval anus, in the last somite. The clitelium is a conspicuous glandular swelling over the somites 32 to 37. Setae – minute, rod-like chitinous appendages. Anus Somites Mouth Figure 7.3 Clitelium
11. It is divided into three segments. The segments are not similar and is referred to as tagmata. The Cockroach
12. 1. The Head Compound eyes (ommatidia) Antennae Gena Ocelli Figure 7.4
13. 2. The Thorax Cervix The cervix (neck) connects the head to the thorax.
15. 2. The Thorax Prothoracic plate Figure 7.6 The prothoracic plate is a broad plate located anteriorly.
16. 2. The Thorax Forewing/Elytrom Cercus Hindwing Figure 7.6 Forewing spread in the mesothorasic area while the hind wing is on the metathorasic area. The hindwing is the one used in flight.
24. Answers to Self Assessment Question 1. Compare and contrast the following invertebrates based on the following:
25. 2. Compare and contrast the tod with fish, other amphibians, reptiles, birds, and mammals based on the following:
26. What is the adaptive significance of segmentation in animals? Segmentation is the division of an animal into similar parts. It's main significance is that it provides a simple way of making a small animal into a larger one - basically by duplicating a segment two or more times an animal can be made bigger without complex alterations. This has particular significance in evolution where it is generally believed that larger animals evolved through a simple genetic mutation which generated multi-segmented forms from non-segmented forms. Segmentation is visible to one extent or another in virtually all larger fauna - from insects and earthworms to vertebrates (the spinal column is an example of segmentation - the repeated use of vertebral disks to create a larger creature than would easily be possible by simple enlarging one vertebra)