CHAPTER 20 Flashcards
ANIMAL STRUCTURE
- Animal Structure has a hierarchy
- Cell= smallest independent unit of life
- Tissue= integrated group of cells that perform a specific function
- Organ= 2 or more types of tissues that together perform a specific task
- Organ System= multiple organs that together perform a vital body function
- Organism= integrated unit made up of a number of organ systems functioning together
STRUCTURE
- Structure fits function in the animal body
- Anatomy = study of structure
- Physiology = how structures function
- The functions of the various parts of the body result from their specific structures
TISSUES
*Tissues are groups of cells with a common structure and function
*The cells composing a tissue are specialized to perform a specific function
*In almost all animals, most body cells are organized into 4 main categories of tissues:
1 Epithelial
2 Connective
3 Muscle
4 Nervous
EPITHELIAL TISSUES
*Epithelial tissue covers body and lines its organs and cavities
*Epithelial tissue occurs as sheets of cells anchored to underlying tissues by a basement membrane
*Categories of Epithelial tissues:
1 Simple: single layer of cells
2 Stratified: Multiple layers of cells
3 Shapes: squamous, cluboidal, columnar
*Epithelial tissue functions in protection, secretion, and exchange
EPITHELIAL TISSUES (SHAPES)
- Clubodial epithelium: cube
- Simple columar: column
- Simple squamous: plate
CONNECTIVE TISSUE
- Connective tissue binds and supports other tissues
- The various types of connective tissue consist of cells in an extracellular matrix
- *Loose connective tissue
- *Fibrous Connective Tissue
- *Adipose Tissue
- *Cartilage
- *Bone
- *Blood
MUSCLE TISSUE
- Muscle tissue functions in movement
- Muscle tissue consists of bundles of long cells called muscle fibers
- *Skeletal muscle: responsible for voluntary body movements
- *Cardiac muscle: forms the contractile tissue of the heart
- *Smooth muscle: lines the walls of the internal organs such as the stomach, bladder, and arteries
NERVOUS TISSUE
- Nervous tissue forms a communication network
- Nervous tissue senses stimuli and rapidly transmits info throughout the body
- The neuron is the structural and functional unit of nervous tissue
- *Specialized to conduct electrical impulses
- *Consists of cell body, axon, and dendrites
- *Nourished by supporting ells known as glia
ORGANS
- Organs are made up of tissues
- Each organ is made of several tissues that collectively perform specific functions
- *In some organs, tissues are arranged in layers
- An organ performs functions that none of its component tissues could carry out alone
12 ORGAN SYSTEMS
- Digestive
- Respiratory
- Circulatory
- Lymphatic
- Immune
- Endocronic
- Excretory
- Reproductive
- Skeletal
- Muscular
- Nervous
- Integumentary
DIGESTIVE SYSTEM
*Ingests and digests food, absorbs nutrients, and eliminated undigested material
(anus, large intestine, small intestine, stomach, liver, esophagus, mouth)
RESPIRATORY SYSTEM
*Exchanges gases with the environment, supplying blood with O2 and disposing of CO2
(lung, bronchus, trachea, larynx, nasal cavity)
CIRCULATORY SYSTEM
*Delivers O2 and nutrients to cells and transports CO2 to the lungs and metabolic waste to the kidneys
(heart, blood vessels)
EXCRETORY SYSTEM
*Removes excess, unnecessary materials from body fluids to help maintain internal homeostasis and prevent damage to the body
(kidney, ureter, urinary bladder, urethra)
ENDOCRINE SYSTEM
*Secretes hormones that regulate body activities, thus maintaining an internal steady state called homeostasis
(ovary, testis, pancreas, adrenal gland, thymus, thyroid gland, pituitary gland)
NERVOUS SYSTEM
*Coordinates body activities by detecting stimuli, integrating information and directing responses
(brain sense organ, spinal cord, nerves)
MUSCULAR SYSTEM
*Moves the body, maintains posture, and produces heat
skeletal muscles
SKELETAL SYSTEM
*Supports the body, protects organs, and provides the framework for muscle movement
(cartilage, bones)
REPRODUCTIVE SYSTEM
- Produces gametes and sex hormones
- Female system supports embryo development and milk production
(male: prostate gland, vas defrens, urethra, penis, testis)
(female: oviduct, ovary, uterus, vagina)
INGUMENTARY SYSTEM
*Protects against physical injury, infection, excessive cold or heat, and drying out
(hair, skin, nails)
LYMPHATIC SYSTEM
*Returns excess body fluid to the circulatory system and functions as part of the immune system
(bone marrow, thymus, spleen, lymph nodes, lymph vessels)
IMMUNE SYSTEM
*Fights off infections
bone marrow, thymus, spleen, lymph nodes, lymph vessels
INTEGUMENTARY SYSTEM
*Skin consists of 2 layers
1 Epidermis: stratified squamous epithelium with many layers of flat cells
2 Dermis: Inner layer of skin that consists of corrective tissue with collagen fibers
*Hair insulates the bodies of most mammals
*Nails are protectieve coverings composed of keratin
STRUCTURAL ADAPTATIONS
- Structural adaptations enhance exchange between animals and their environment
- An animal must exchange materials with its environment
- *Oxygen and nutrients enter
- *CO2 and metabolic wastes exits
- *Only molecules dissolved in water can move across plasma membrane
HOMEOSTASIS
- Homeostasis depends on negative feedback
- In negative feedback, a change in available triggers mechanisms that reverse the change
- Negative feedback mechanisms keep internal variables fairly constant, with small fluctuations around set points
- In animals, most control centers that maintain homeostasis are located in the brain
THERMOREGULTION
- Thermoregulation = process by which animals maintain their body temperature
- *Endotherms are warmed mostly by the heat generated by metabolism (internal)
- *Ectotherms gain heat from external sources (external)
ANIMALS
- Animals regulate their internal environment
- The internal environment of a vertebrate is the interstitial fluid surrounding the cells
- In response to changes in external conditions, animals regulate their internal environment to achieve homeostasis : an internal steady state
- Homeostasis is a dynamic state with constant small fluctuations
STRUCTURAL ADAPTATIONS
- Larger, complex animals have less surface area relative to volume
- *Rely on specialized surface for exchanging materials with the environment
- Interstitial fluid provides for indirect exchange between blood and body cells
- Branching and folding increases surface area of the lungs, intestines, and kidneys
