Epithelial Tissue in Animals

What are some functions of epithelial coverings in animals?

Protection, secretion, gas exchange, temperature regulation, sensory reception

What is the purpose of the cuticle secreted by invertebrate epithelium?

To provide a protective or supportive layer of nonliving material

Give an example of an animal that secretes a shell made mainly of calcium carbonate.

Corals and mollusks

How does the earthworm epithelium promote efficient diffusion of gases?

By secreting lubricating mucus Signup and view all the answers

What is the purpose of the feathers in birds and fur in mammals?

Insulation Signup and view all the answers

What is sebum, and what is its function?

A mixture of fats and waxes; inhibits the growth of harmful bacteria Signup and view all the answers

What is the name of the deepest layer of the epidermis?

Stratum basale Signup and view all the answers

What structure do amphibians have on their skin that helps in defense?

Poison glands Signup and view all the answers

What is the pigment produced by pigment cells in the skin?

Melanin Signup and view all the answers

What is the main function of the oil (sebaceous) glands in mammals?

Produce sebum to inhibit the growth of harmful bacteria Signup and view all the answers

How does the epithelial tissue in invertebrates contribute to efficient gas exchange?

The earthworm epithelium secretes lubricating mucus that promotes efficient diffusion of gases across the body wall. Signup and view all the answers

What are some examples of nonliving material layers secreted by invertebrate epithelium for protection?

In insects and many other animals, the secreted material forms an outer covering called a cuticle. Some animals, including corals and mollusks, secrete a shell made mainly of calcium carbonate. Signup and view all the answers

How do epithelial cells contribute to communication in animals?

Epithelial cells may contain cells that secrete odorous secretions used for communication or marking trails. Signup and view all the answers

What are some functions of modified epithelial cells as sensory cells?

Epithelial cells may be modified as sensory cells that are selectively sensitive to light, chemical stimuli, or mechanical stimuli. Signup and view all the answers

What are the main differences in skin derivatives among fishes, amphibians, reptiles, mammals, and birds?

Fishes have bony or toothlike scales, amphibians have naked skin covered with mucus and poison glands, reptiles have epidermal scales, mammals have hair and sweat glands, birds have feathers for insulation. Signup and view all the answers

Explain the significance of sebum secretion by oil glands in mammals.

Sebum, a mixture of fats and waxes, inhibits the growth of harmful bacteria on the skin surface. Signup and view all the answers

How do epidermal cells in the skin of vertebrates produce melanin and what is its function?

Epidermal cells in stratum basale and dermis produce melanin, a pigment contributing to skin color. Signup and view all the answers

What is the role of keratin in the skin of vertebrates?

Keratin is an elaborately coiled protein that gives the skin mechanical strength as cells mature towards the skin surface. Signup and view all the answers

Describe the basic structure of the epidermis in vertebrate skin.

The epidermis consists of several layers, with the deepest layer being the stratum basale and the most superficial being the stratum corneum. Signup and view all the answers

How does the skin of mammals, including humans, utilize oil glands and hair follicles for protection?

Oil glands secrete sebum, which inhibits bacterial growth, and empty into hair follicles where sebum spreads over the skin surface. Signup and view all the answers