BIOS255 Comprehensive Exam Review Questions and Answers 100% Pass

BIOS255 Comprehensive Exam Review Questions and Answers 100% Pass Homeostasis - ANSWER -* Presence of stable internal environment * Failure to maintain homeostasis leads to illness or death Homeostatic Regulation - ANSWER -Physiological adjustment to preserve homeostasis in variable environments Feedback - ANSWER -Stimulation of a receptor triggers response that changes environment at that receptor Negative Feedback - ANSWER -* Effector opposes or negates the original stimulus * Minimizes change * Primary mechanism of homeostatic regulation in the body * Dynamic process: Set point varies with varying environments & activity levels Negative Feedback Receptors - ANSWER -Temperature receptors in skin & brain are stimulated & send signals to the control center Negative Feedback Control Center - ANSWER -The temperature control center received information from the two sets of temperature receptors & sends commands to the effectors Negative Feedback Effectors - ANSWER -Sweat glands & smooth muscle in the walls of blood vessels supplying the skin respond 2 | P a g e Created by Grace Amelia © 2025, All Rights Reserved. Positive Feedback - ANSWER -* Stimulus produces a response that exaggerates or enhances the original change (rather than opposing it) * Tends to produce extreme responses * Does not restore homeostasis Positive Feedback Loop - ANSWER -* Escalating cycle * Typically occurs when a potentially dangerous or stressful process must be completed quickly before the body can restore homeostasis Steps of Positive Feedback in Blood Clotting - ANSWER -1. Damage to cells in the blood vessel wall releases chemicals that begin the process of blood clotting 2. The chemicals start chain reactions in which cells, cell fragments, & soluble proteins in the blood begin to form a clot 3. As clotting continues, each step releases chemicals that further accelerate the process 4. This escalating process is a positive feedback loop that ends with the formation of a blood clot, which patches the vessel wall & stops the bleeding Epithelial Tissue - ANSWER -* Epithelia * Glands (Exocrine & Endocrine) Functions of Epithelial Tissue - ANSWER -* Provide physical protection * Control permeability * Provide sensation * Produce specialized secretions Characteristic of Epithelial Tissue - ANSWER -* Specialized contacts with other cells 3 | P a g e Created by Grace Amelia © 2025, All Rights Reserved. * Polarity (different ends of cell do different things) * Avascularity (NO blood supply) * Regeneration (can divide to make new cells) * Cellularity (lots of cells in close contact) Characteristics of Epithelial Tissue: Specialized Contacts - ANSWER -Epithelial cells are held close together by cell junctions Features of Epithelial Tissue - ANSWER -* Surfaces: Apical surface-Faces exterior of body or internal space; Base- Attached to underlying tissues * Polarity: Refers to structural differences between exposed & attached surfaces Connective tissue overview - ANSWER -* Varies widely in appearance & function (Found throughout the body, but never exposed to surface) * Ranges from highly vascular to avascular * Many contain sensory receptors that detect pain, pressure, temperature, & other stimuli 3 basic components shared by connective tissues - ANSWER -1. Specialized cells