MAT NU110: Exam 2 review | 2026 Complete Solutions

1. Differentiate the Layers, Functions, and Accessory Structures of the Skin
 Epidermis: Outer protective layer, provides temperature regulation, and has a high
turnover rate (Stratum Corneum).
 Dermis: Contains blood vessels, nerve endings, and accessory structures; provides
structural support and nourishment.
 Subcutaneous Layer (Adipose Tissue): Insulation, energy storage, and connects
skin to deeper tissues.
 Sebaceous Glands: Secrete oil (sebum) to lubricate and protect skin and hair.
 Sudoriferous Glands:
o Eccrine glands – Assist with cooling and found all over the body.
o Apocrine glands – Found in axillae and groin.
 Hair: Composed of keratin, conserves body heat.
 Nails: Composed of keratin, protect fingers and toes and assist in grasping.

2. Describe Thermoregulation of the Skin
 Regulated by the Hypothalamus:
o Increased Body Temperature:
 Sweat glands produce perspiration to cool the skin.
 Blood vessels dilate, bringing blood to the surface to dissipate heat.
o Decreased Body Temperature:
 Skeletal muscles contract (shivering) to generate heat.
 Blood vessels constrict to conserve core body heat.
 Sweat gland activity decreases.

3. Identify the Purpose of Keratin and Melanin in the Integumentary System
 Keratin: Strengthens skin, hair, and nails; protects against damage.
 Melanin: Pigment that protects skin from UV radiation and gives skin its color.

Respiratory System
4. Summarize the Structures of the Respiratory System and Their Functions
 Nasal Cavity: Filters, warms, and humidifies air.
 Pharynx (Nasopharynx, Oropharynx, Laryngopharynx): Transports air to the
respiratory tract.
 Larynx: Houses vocal cords; contains the epiglottis to prevent food entry into the
trachea.
 Trachea: Air passage reinforced with cartilage rings to remain open.
 Bronchi: Further divides into smaller branches, continues air filtration.
 Bronchioles: Smallest air passages leading to alveoli.
 Alveoli: Site of gas exchange with capillaries.
 Diaphragm & Intercostal Muscles: Essential in breathing by expanding and
contracting the lungs.

5. Differentiate Between Oxygenation and Perfusion
 Oxygenation: Exchange of oxygen and carbon dioxide in the lungs.
 Perfusion: Transport of oxygen via the cardiovascular system to tissues.

, 6. Outline the Mechanisms of Air Movement in and out of the Lungs
 Inhalation (Active Process):
o Diaphragm contracts: Moves downward, increasing lung volume.
o Intercostal muscles contract: Expands the rib cage.
 Exhalation (Passive Process):
o Diaphragm relaxes: Moves upward, decreasing lung volume.
o Intercostal muscles relax: Chest returns to normal position.

7. Summarize the Transport of Oxygen and Carbon Dioxide
 Oxygen Transport: Binds to hemoglobin in red blood cells and is delivered to
tissues.
 Carbon Dioxide Transport:
o Dissolved in plasma.
o Bound to proteins.
o Converted into bicarbonate to regulate blood pH.

8. Relationship Between Carbon Dioxide and Blood pH
 Increased CO₂ = More Hydrogen Ions = Lower pH (Acidic)
 Decreased CO₂ = Fewer Hydrogen Ions = Higher pH (Alkaline)

9. Discuss How the Respiratory System Responds to Neural and Chemical Controls
 Neural Controls:
o Medulla & Pons: Regulate respiratory rate and depth.
o Phrenic Nerve: Stimulates the diaphragm.
 Chemical Controls:
o Chemoreceptors (Aorta & Carotid Arteries): Detect changes in CO₂ and pH
levels.
o Lung Stretch Receptors: Prevent overinflation.

Integumentary System
1. Which of the following is the outermost layer of the skin?
o A) Dermis
o B) Epidermis
o C) Hypodermis
o D) Subcutaneous layer
2. The dermis contains which of the following structures?
o A) Blood vessels and nerves
o B) Sweat and sebaceous glands
o C) Hair follicles
o D) All of the above
3. Which layer of the skin provides insulation and energy storage?
o A) Epidermis
o B) Dermis
o C) Hypodermis
o D) Stratum basale