Flashcards in Chapter 1-Intro to physiology Deck (13):
What are the four major cell/tissue types.
The four major cells/tissue types are Neurons and Nervous tissue, Muscle cells and Muscle tissue, Epithelial cells and Epithelial, and Connective tissue.
What are neuron and nervous tissue?
Neurons and nervous tissue such as motor neurons, cortical interneurons, etc are specialized for sending and receiving information.
What are Muscle tissue and Muscle cells specialized for.
Muscle cells and muscle tissue such as cardiac myocytes, skeletal muscle, etc. are specialized for contraction.
What are Epithelial cells and epithelial tissue
Epithelial cells and epithelial tissue such as intestinal epithelial cells consists of cells that form membranes, which cover and line the body surfaces, and of glands, which are derived from these membranes, found on organs, glands, and lining body cavities. The most common gland are endocrine gland and exocrine glands.
What are the differences between endocrine glands and exocrine glands?
Endocrine glands secrete molecules (usually hormones) directly into the blood stream. i.e. pancreatic and thymus glands. Exocrine glands utilize a duct and secrete molecules into a body cavity, or to the exterior of the body. i.e. the stomach, salivary glands, and sweat glands.
what are connective tissues?
Connective tissue cells i.e bone cells, blood cells, fat cells are characterized by very few cells and lots of extracellular materials.
What is homeostasis?
Homeostasis is the body's ability to maintain a relatively stable internal environment despite fluctuations in the external environment. Essential for survival and function of all cells. Deviation from homeostasis indicates disease. Homeostasis is most often accomplished through negative feedback.
What is a negative feedback?
Negative feedback Involves returning internal conditions to a ”set point.
A negative feedback loop helps return internal conditions to a set point when they deviate too far outside of an acceptable range. The input and the output are opposites. Example: shivering when you get cold.
What does negative feedback involves?
Negative feedback Involves:
Sensors in the body to detect change and send information to the integrating center.
Integrating center assesses change around a set point. The integrating center then sends instructions to an effector.
Effector makes the appropriate adjustments.
Why do people often shiver when they have a fever?
Fever is a physiological response which involves changing the body temperatures set point (hypothalamus). Elevated set point causes heat producing physiological responses such as vasoconstriction and shivering. The shivering helps make fever happen. Individuals with fever feel cold because the set point has changed.
What are antagonistic effectors?
Antagonistic effectors are opposing effectors that move conditions in opposite directions.
This maintains conditions within a certain normal range, or dynamic constancy.
When you are hot, you sweat; when you are cold, you shiver. These are antagonistic reactions.
What is positive feedback?
Positive feedback moves conditions further away from a set point. The input and the output in a positive feedback loop are the same.
Example: uterine contractions during child birth.
Release of oxytocin causes the uterus to contract. This pushes the baby’s head against the cervix, activating stretch receptors that signal to the hypothalamus. This results in more oxytocin release, which results in stronger contractions.