Integument - General and Fishes

Question 1

What are the two fundamental layers of the skin of vertebrates?

Answer 1

Epidermis and Dermis

Question 2

What type of tissue is the epidermis

Answer 2

Epithelial tissue

Question 3

What type of tissue is the dermis

Answer 3

Connective tissue

Question 4

Where does the dermis come from in embryonic development

Answer 4

Mesoderm

Question 5

Where does the epidermis come from in embryonic development

Answer 5

Ectoderm

Question 6

What cell types give the skin color in vertebrates?

Answer 6

Melanocytes

Question 7

Where do melanocytes come from in embryonic development?

Answer 7

Neural Crest

Question 8

How can vertebrates change their color in general?

Answer 8

Pigment cells, Chromatophores, change color in general.

For fish and amphibians, they are found in the dermis. In some reptiles, they are found in the epidermis.

Question 9

Melanophores

Answer 9

Black/Brown

Question 10

Iridophores

Answer 10

Silver/White

Question 11

Xanthophores

Answer 11

Yellow/Orange

Question 12

Erythrophores

Answer 12

Red

Question 13

What layers of the skin are involved in the development of fish scales?

Answer 13

Epidermis and Dermis

Question 14

_____?___ in the ___?_____ secrete enamel.

Answer 14

Ameloblasts in the Ectoderm secrete enamel

Question 15

? in the ? form dentine.

Answer 15

Odontoblasts in the Mesoderm form dentine.

Question 16

Specialized cells involved in the production of enamel, and their role is essential for the protection and function of various structures, including fish scales and teeth in vertebrates

Answer 16

Ameloblasts

Enamel: the outermost, hard, and protective layer of teeth

Question 17

Specialized cells involved in the formation of dentine, a critical component of teeth in vertebrates, including fish. They are essential for tooth development, maintenance, and repair, contributing to the structural integrity of teeth throughout an animal’s life

Answer 17

Odontoblasts

Dentine: a hard and mineralized tissue that makes up the bulk of a tooth’s structure beneath the enamel or outermost layer

Question 18

Placoid scales

Answer 18

• Cartilaginous fish, such as sharks and rays.
• Dentine and Enamel.
• Enamel and Dentine-like properties create a smooth and hard mineralized tissue for placoid scales that is used for protection against predators

Placoid scales, like teeth, contain a hard, mineralized tissue. This tissue is not true dentin, but it is similar in that it provides rigidity and protection to the scales. It is sometimes called “placoid dentine” or “denticle dentine” due to its mineralized nature. Provides protecting against predators.

Question 19

Ganoid scales

Answer 19

• In bony fishes, such as gars and Actinopterygians.
• Three layer scales
• The first layer is multilayered enamel
• The second layer is a form of dentine
• The third layer is a lamellar bone

Lamellar bone in ganoid scales is significant as an ancient adaptation that provides protection and structural integrity to certain fish species.

Question 20

Elasmoid scales

Answer 20

• Teleost fish
• Ctenoid - perches
• Ctenoid are tooth edged
• Cycloids - salmon/trout
• Cycloids are smooth edged
• Contain only enamel

Question 21

Cosmoid scale

Answer 21

• Fleshy-finned fishes, such as Lungfishes fish.
• Four layers
• First layer is thin enamel
• The second layer is cosmine, dentine
• The third layer is vascular bone
• The fourth layer is lamellar bone