HOSA Anatomy and Physiology Practice Test

• In the ABO system (ignoring Rh factor), type O is considered the universal donor because it lacks A or B antigens on the red cells.
• If Rh factor is included, O negative is the true universal donor for red blood cell transfusions.

Erythropoietin is primarily secreted by the kidneys to stimulate red blood cell production in the bone marrow.

The small intestine is where the majority of nutrient absorption occurs. Without it, the body cannot properly absorb nutrients needed for survival.

Melanocytes produce melanin, the pigment primarily responsible for skin, hair, and eye color.

The cell (plasma) membrane is a semipermeable barrier that encloses the cytoplasm and regulates movement of substances into and out of the cell.

In type I diabetes, the beta cells of the pancreas fail to produce adequate insulin, causing dysregulation of blood glucose.

The vagus nerve (CN X) innervates thoracic and abdominal viscera, playing a key role in parasympathetic control of the heart, lungs, and digestive tract.

The pectoral region refers to the chest area. Of the listed options, only the heart is located in the thoracic (chest) region. The other structures (spleen, knee, head, forearm) are located in different body regions.

Basophils (and mast cells) release histamine (inflammatory response) and heparin (anticoagulant).

Hemocytoblasts (hematopoietic stem cells) reside in the bone marrow and differentiate into all types of blood cells.

• The middle ear contains the auditory ossicles (malleus, incus, stapes) and the eustachian tube, which equalizes pressure.
• The vestibular canal and labyrinth are part of the inner ear; alveoli are in the lungs.

• Rods are photoreceptor cells in the retina sensitive to dim light and responsible for peripheral (side) vision.
• Cones are responsible for color vision and sharp central vision.

• The lumbar region has 5 vertebrae (L1–L5).
• Cervical has 7, thoracic has 12, sacral 5 (fused), and coccygeal 3–5 (fused).

• The five named regions of the vertebral column are: cervical, thoracic, lumbar, sacral, and coccygeal.
• The spinal cord itself is often similarly described in cervical, thoracic, lumbar, sacral, and coccygeal segments.

• The coronal plane (also called the frontal plane) is a vertical plane that divides the body into anterior (front) and posterior (back) portions. This is in contrast to:
• Transverse plane (superior/inferior division)
• Sagittal plane (right/left division)
• Midline (direct vertical line dividing right and left sides).

The mitochondrion is often called the “powerhouse” of the cell because it produces ATP, the cell’s main energy currency.

• Prolactin stimulates milk production in the mammary glands.
• Oxytocin triggers the milk ejection (let-down) reflex but does not initiate milk production.

The urinary bladder is a muscular, distensible organ that temporarily stores urine before excretion.

• The cerebellum is responsible for coordinating voluntary muscle movements, maintaining posture, and balance.
• The medulla oblongata controls autonomic functions (heart rate, breathing).
• The hypothalamus regulates endocrine activity, temperature, etc.

• Phagocytosis (“cell eating”) is when a cell engulfs large particles or other cells.
• Pinocytosis (“cell drinking”) involves taking in fluid and dissolved substances.
• Exocytosis is expelling substances from a cell.

The diaphragm is a large, dome-shaped muscle that physically separates the thoracic and abdominal cavities and is crucial for breathing.

• Holocrine glands release secretions by the rupture of the entire cell, as in sebaceous (oil) glands.
• Merocrine (e.g., sweat) and apocrine (e.g., mammary) glands use different modes of secretion.

BMR is the amount of energy expended while at rest, needed to maintain vital functions such as breathing, circulation, and cell production.

Thermogenesis refers to heat production (e.g., shivering), not just the baseline energy requirement.

The hyoid is a U-shaped bone in the anterior neck, unique because it does not directly articulate with any other bone.

• Renin is an enzyme (produced by the kidneys) involved in blood pressure regulation, not a neurotransmitter.
• Dopamine, epinephrine (adrenaline), serotonin, and histamine can all act as neurotransmitters.