How Do Organisms Respond to Change? Animal Physiology: How Do Organisms Respond to Change?

What Are The Underlying Principles of Physiology? Cells of multicellular organisms are hierarchically arranged Multicellular organisms are more than the sum of their parts Multicellular organisms function best within stable internal environments Feedback systems control many physiological processes

Cells of Multicellular Organisms are Hierarchically Organized Multicellular organisms have cells that are organized into tissues Groups of similar cells performing a similar function

Four Types of Tissues Epithelial Covers surfaces throughout the body ( inside and out) and protect what they cover. Three types based on cell shape: Columnar, Cuboidial, Squamous.

Four Types of Tissues Connective Usually composed of living cells surrounded by nonliving matrices. Found throughout the body. Various Functions

Four Types of Tissues Muscle Highly contractile Major function: move internal parts, or along with bones to move body as a whole. Three types: Striated Smooth Cardiac

Four Types of Tissues Nerve tissue Abundant throughout the body Primary function is to relay information from the external and internal environments to the brain. Process that other information , and relay messages from the brain to all internal body parts.

Organs Complex systems of tissue that work together to perform common functions. Examples: Stomach Skin Forearm

Organs are Organized into Organ Systems Organ Systems: A group of organs that work together to perform a specific function.

Multicellular Organisms are More Than The Sum of Their Parts They are synergisms An instance of the combined effect of several actions being greater than the sum of the individual actions.

Multicellular Organisms Function Best Within Stable Environments Homeostasis Maintaining a constant internal environment Multicellular organisms function best under nearly steady-state internal conditions.

Feedback Systems Control Many Physiological Processes Regulation of a process by which a component from a later stage in the process controls its own production by influencing an earlier stage in the process. 2 types Positive and Negative

Additional Points to Remember: All physiological processes are a cellular phenomena Example: Digestion of nutrients in intestine and their movement through the blood There is a relationship between form and function Example: structure of cell is related to its function

Additional Points to Remember: Tolerable ranges of internal and external conditions often vary from one organism to the next. Example: algae living in near boiling hot springs

Additional Points to Remember: Evolution often results in increasing complexity, but not always. Example: the digestive systems of various animals Plants are structurally and physiologically less complex than plants. Example: most advanced plants produce flowers which consists of only three organ systems.

How Do Organisms Obtain Information From Their Environment? Organisms need to assess: What is the current state of the environment? What changes are taking place? What adjustments need to be made to adapt to these changes? Two systems devoted to answering these questions: Endocrine and Nervous systems

Endocrine Systems Most primitive environmental monitoring system Based on the presence of absence of chemicals These systems produce hormones Chemical messages

Endocrine Systems Hormones are respond to long-term changes in an organism’s environments. Key in such processes as growth, maturity, preproduction and metabolism.

Nervous Systems Allows for quick adjustment to environmental conditions that may be necessary for survival. Found only in animals Basic cellular unit in vertebrates is neurons. Allows the brain to be connected with all parts of the body. This system evolved from rather simple networks into highly complex systems . composed of numerous lateral nerves that feed information into and out of highly complex, centralized nerve cords and brains.

How Do Organisms Acquire and Process Nutrients and Wastes? We are all dependent on our surroundings. Ultimately dependent on the sun Each of these systems depend on diffusion and osmosis to move nutrients and water between cells, tissues, and organs systems.

Primitive Organisms Process Nutrients and Wastes Bacteria and fungi digest their food outside the cells They obtain nutrients by excreting enzymes onto their food. The enzymes break down complex compounds into simpler ones.

Multicellular Organisms Have Digestive Systems Among animals, digestive systems (absent in sponges) evolved from those with Single openings Example: jellyfish and flatworms Into simple, undifferentiated tubes with two openings Example: Roundworms To complex, convoluted tubes with accessory organs Example: other animals such as humans

Symbiosis

Animals Use Respiration to Obtain the Gases They Need Three basic types of systems: Skin- the outer body covering Gills Outpockets of tissue that work best in water Lungs Inpockets of tissue that work best in air Share two characteristics: Extensive surface area and thin, moist cell layers to facilitate diffusion

Animals Use Respiration to Obtain the Gases They Need Simple organisms such as hydra and flatworms exchange gases via their skin.

Animals Use Respiration to Obtain the Gases They Need Insects have a system of internal tubes that open to the outside thought spiracles and connect to internal air sacs.

Animals Use Respiration to Obtain the Gases They Need Bony fish bring water with oxygen into mouth and it passes over gills where gaseous exchange occurs.

Animals Use Respiration to Obtain the Gases They Need Mammals use muscles to pump air containing oxygen into the lungs where gaseous exchange occurs. Structure of lungs increases the surface area.