The Vertebrate body plan

Question 1

Body Plan defintion

Answer 1

• Body plan: The entire structure of an animal, its organ systems and the integrated functioning of its parts are known as its
  
  • fundamental aspect = symmetry

Question 2

Triploblastic

Answer 2

• Cleavage partitions the cytoplasm of one large cells into many smaller cells
  
  • process by which layers of tissue form in the blastocyst and take specific positions relative to each other in the body
  • close relationship of these layers allows exchange of signals (e.g. growth factors) among tissues that trigger cell differentiation and organ formation
• During gastrulation, body forms three germ layers (triploblastic)
  
  • outside = ectoderm
  • Middle = endoderm
  • layer between the two = mesoderm
  • different structures derive from different layers

Question 3

Neurulation

Answer 3

• Is the process of nerve formation

- occurs through invagination

Question 4

Coelom

Answer 4

• Coelom: animals that have a coelom (body cavity) form two major lines
  
  • coelomate animals have body cavity that develops within the embryonic mesoderm
• tube within a tube body plan (body cavity lined with periotneum)

Question 5

Structures derived from tree embryonic germ layers

Answer 5

• Ectoderm: Epidermis of skin and its derivatives
  
  • Epithelial lining of mouth and rectum
  • Sense receptors in epidermis
  • cornea and lens of eye
  • tooth enamel
• Mesoderm: -notochord
  - skeletal system, muscular system
  - Urinary system
  - circulatory and lymphatic system
  
  • dermis of skin
  • Lining of body cavity
• Endoderm: -epithelial lining of digestive tract
  - liver, pancrease, thymus
  - lining of urethra, urinary bladder and reproductive system

Question 6

Vertebrates Characteristics (5)

Answer 6

1. Deuterostome coelomtates
2. With bilateral symmetry
3. Tube-within-a-tube body plan
4. Three well developed germ layers
5. Endoskeleton with closed circulatory system and ventral heart