Chapter 1 Flashcards
Anatomy?
Anatomy is structure. Anatomy studies the structure of body parts and their relationships to one another. Anatomy
Physiology?
Physiology is function.
Physiology is
explainable only in terms of the underlying anatomy.
6 levels of structural organization?
Chemical level:
Atoms combine to form molecules
Cellular level:
cells are made up of molecules
Tissue level:
Tissues consist of similar types of cells
Organ level:
Organs are made up of different types of tissue. smooth muscle tissue, connective tissue, epithelial tissue.
Organ system level: consist of different organs that work together independently.
Organismal level: made up of many organ systems
Different systems?
Digestive:
Takes in nutrients, breaks them down, and eliminates unabsorbed
matter (feces).
Respiratory system: Takes in oxygen and eliminates carbon dioxide Cardiovascular system: Via the blood, distributes oxygen and nutrients to all body cells and delivers wastes and carbon dioxide to disposal organs.
Urinary system: Eliminates nitrogenous wastes and excess ions. Integumentary system: Protects the body as a whole from the external environment. ie) skin etc
Skeletal System: Protects and supports body organs, and provides a framework the muscles use to cause movement. Blood cells are formed within bones. Bones store minerals.
Muscular System:
Allows manipulation of the environment,
locomotion, and facial expression.
Maintains posture, and produces heat
Lymphatic system:
Picks up fluid leaked from blood vessels and returns it to blood. Disposes of debris in the lymphatic stream. Houses white blood cells (lymphocytes)
involved in immunity. The immune response mounts the attack against foreign substances within the body.
Nervous system?
Nervous System
As the last-acting control system of the body, it responds to internal and external changes by activating appropriate
muscles and glands.
Endocrine system?
Glands secrete hormones that regulate processes such as growth, reproduction,
and nutrient use (metabolism) by body cells.
Homeostasis?
- Maintenance of a stable internal environment.
- All systems play a role.
- Nervous and endocrine are control systems.
- Negative feedback mechanisms maintain homeostasis****
- has 3 big players
3 big players in homeostasis?
receptor, senses change.
control center, gets this and makes a plan.
Effector gets motor output and carries it out.
Negative feedback:
Get hot, sweat, take shirt off. Get cold, shiver, put shirt on.
- Regulation of blood sugar in humans - When blood sugar rises, insulin sends a signal to the liver, muscles and other cells to store the excess glucose. Some is stored as body fat and other is stored as glycogen in the liver and muscles.
Likewise, when blood glucose is too low glucagon is released to breakdown glycogen into glucose.
Mechanism causes variable to change in a direction opposite to that of the initial change (i.e. challenge to the system)
Variable comes back to it’s normal value.
Positive feedback:
NOT useful for maintaining stable conditions
Response causes variable to deviate further from it’s original value
Very few instances where it is used in the body
- Contractions:
Oxytocin intensifies labour contractions. Likewise contractions cause more oxytocin to be released. Birth ends the stimulus.
- Blood clotting:
Once a blood vessel has been damage, blood elements called platelets begin to cling to the site and release chemicals that attract more platelets.
Male and Female reproductive systems:
Overall function is production of offspring. Testes produce sperm and male sex hormone, and male ducts and glands aid in delivery of sperm to the female reproductive tract. Ovaries
produce eggs and female sex hormones. The remaining female structures serve as sites for fertilization and development of the fetus. Mammary glands of female breasts produce milk to nourish the newborn.
Metabolism:
is a broad term that includes all chemical reactions that occur within body cells. It includes breaking down substances into simpler building blocks (the process of catabolism), synthesizing more complex substances from simpler building blocks (anabolism), and using nutrients and oxygen to produce (via cellular respiration) ATP, the energy-rich molecules that power cellular activities. Metabolism depends on the digestive and respiratory systems to make nutrients and oxygen available to the blood, and on the cardiovascular system to distribute them throughout the body. Metabolism
is regulated largely by hormones secreted by endocrine system glands.
