Exploring the Origins of Hair and Nails

The video tutorial explores the integumentary system, focusing on the structure and growth of nails and hair. It explains how nails are part of the epidermis, composed of keratin-packed dead cells, and highlights the faster growth rate of fingernails compared to toenails. The tutorial also covers hair growth from the dermis, detailing the role of hair follicles and keratin. Additionally, it discusses the arrector pili muscle, responsible for goose bumps and hair standing, and its vestigial nature in humans compared to its functional role in animals like polar bears.

What are the components of the integumentary system?

• None of the above

• Skin and appendages

• Only the appendages

• Only the skin

What is the nail root attached to?

• Hypodermis

• Hair follicle

• Dermis

• Epidermis

What substance is packed into the dead cells of the nail?

• Collagen

• Elastin

• Melanin

• Keratin

What is the topmost layer of the skin called?

• Dermis

• Hypodermis

• Epidermis

• Subcutaneous layer

Which grows faster, fingernails or toenails?

• Both grow at the same rate

• Toenails

• Neither grows

• Fingernails

Where does hair growth originate?

• Nail root

• Hypodermis

• Dermis

• Epidermis

What is the function of the arrector pili muscle?

• To produce sweat

• To generate heat

• To make hair grow faster

• To make hair stand up and create goosebumps

What type of muscle is the arrector pili muscle?

• Smooth muscle

• Cardiac muscle

• Skeletal muscle

• Voluntary muscle

What is the purpose of hair standing on end in animals like polar bears?

• To create a warm insulating layer

• To attract mates

• To scare predators

• To help them swim

What is the term for a structure that is currently useless or not functional anymore?

• Primary

• Vestigial

• Functional

• Secondary