Cells/Organ Systems/Skeletal System/Muscular System Flashcards
What are the four major types of tissues found in the body? Where would you find them?
- Epithelial: sheets of cells that line or cover various surfaces and body cavities (skin/lining of mouth/digestive tract/lungs/bladder/kidney tubules)
- Connective: supports the softer organs of the body/connects parts of the body together (diverse in where they are located)
- Muscle: cells that are specialized to shorten or contract resulting in movement of some kind (heart, skeletal muscle of tendons, smooth muscle of hollow organs
- Nervous: specialized for generating and transmitting electrical impulses throughout the body (brain, spinal cord, nerves)
Structure/Location/Function of each tissue discussed in class
How can you differentiate one tissue type from another?
-by the type of cells it contains
Difference between an endocrine and an exocrine gland
- Endocrine Glands: secrete products (hormones) into the blood for distribution throughout the body
- Exocrine Glands: secrete products into hollow organs or ducts (glands of mouth that secrete saliva and skin that secretes sweat)
What kind of fibers are found in connective tissue/what are their characteristics & functions?
- Collagen Fibers: made of protein/confer strength
- Elastic Fibers: made primarily of elastin/can stretch without breaking
- Reticular Fibers: made of collagen/internal structural framework for soft organs like the liver, spleen, lymph nodes
What are the components of blood?
- WBCs: immune defense
- RBCs: transport oxygen and nutrients and waste products of cells metabolism
- Platelets: participate in clotting process
What are the major cavities of the body/location/organs that are in each?
Anterior Cavities
- Abdominal Cavity- stomach area/ contains digestive organs, kidneys, liver etc.
- Pelvic Cavity- groin area/ contains bladder
- Thoracic Cavity- chest area/contains heart and lungs
Posterior Cavities
- Cranial Cavity- head/contains brain
- Spinal Cavity- the back/ contains the spine
What are the two layers of the skin and what types of cells/ extracellular materials are found in each?
- Epidermis: outer layer of epithelial tissue, stratified squamous epithelial cells
keratinocytes: provide tough waterproof protein (keratin)
melanocytes: give skin its pigment (melanin) - Dermis: inner layer of connective tissue/supports tissues
fibroblasts: produces collagen and other fibers
mast cells: releases histamine during inflammatory responses
wbcs
fat cells
collagen&elastin fibers for strength and elasticity
What are the functions of the skin?
- protection from dehydration
- protection from injury
- defense against invasion by bacteria and viruses
- regulation of body temperature
- synthesis of vitamin D
- sensation
What are the major types of cell junction/what function does each perform?
- Tight Junctions: seal the plasma membrane tightly together (digestive tract lining/bladder lining)
- Adhesion Junction/Spot Desmosomes: permit some movement between cells/allow tissues to stretch and bend (skin)
- Gap Junction: protein channels enable movement of materials between cells
What are cell junction constructed of?
-proteins
How is homeostasis maintained in the body?
-by negative feedback where deviations from the desired conditions are automatically detected and counteracted
Positive & Negative Feedback
Positive Feedback: change in controlled variable causes a series of events that amplifies original change (ex. childbirth)
-not a mechanism for maintaining homeostasis
Negative Feedback: deviations from normal are detected and counteracted (ex. homeostasis of body temperature
control variable, sensor, control center, effector
Four components of negative feedback system/function of each:
- Controlled Variable: any physical or chemical property that might vary from time to time and must be controlled to maintain homeostasis
- Sensor: monitors current value of controlled variable and sends info to control center
- Control Center: receives input from the sensor and compares it to the correct, internally set value of the controlled variable
- Effector: takes necessary action to correct the imbalance
The 11 Major Body Systems and their Functions:
Muscular: generates heat/produces movement
Urinary: maintains volume of body fluid/excretes waste
Respiratory: exchange gases/produce sound
Digestive: provides body with water and nutrient
Endocrine: produces hormones that regulate body functions/integrative functions
Reproductive: egg, sperm, genitals
Skeletal: protects, supports, stores minerals, produces blood cells
Lymphatic: returns excess tissue fluid to circulatory system, defense responses
Integumentary: protects from injury, infection, dehydration/ receives sensory input
Nervous: detects external and internal stimuli
Circulatory: transports materials to and from cells
Four Types of Tissue Membranes (location/function)
- Serous: line and lubricate internal body cavities/reduce friction between organs
- Mucous: lines airways, digestive tract, reproductive tract/lubricate surface, capture debris
- Synovial: line spaces in movable joints/lubricate the joint
- Cutaneous: form outer covering (skin)
What is the structure of compact and spongy bone?
Compact Bone: forms shaft and ends/ contains marrow space
Spongy Bone: trabeculae form lattice like supports/spaces may contain red bone marrow
***Process of bone formation (ossification) in the fetal skeleton
Early Fetal Development: cartilage model forms/formed by chondroblasts (cartilage forming cells)
Later Fetal Development: osteoblasts replace cartilage with bone
Childhood: primary and secondary ossification sites are formed
Adolescence: elongation of growth plates
What bones make up the appendicular and axial skeleton?
Appendicular: bones of the appendages and their attached structures
-pectoral girdle, arms, pelvic girdle, legs
Axial: midline of the body
-skull, sternum, ribs, vertebral column
How can you identify cervical, thoracic, and lumbar vertebrae?
Structure of skeletal muscle
- Muscle Cell(fiber): contains many individual myofibrils
- Myofibril: cylindrical structures arranged in parallel
- Actin Thin Filament
- Myosin Thick Filament
- Sarcomere: segment of myofibril from one z line to the next
- Z-line
- Fascicle: bundles of muscle
Structure of skeletal muscle (contd.)
- Sarcoplasmic Reticulum: membrane bound chambers
- Troponin:
- Tropomysin: protein involved in muscle contraction
- T-tubule: tubelike extensions of the cell membrane
What is a sarcomere/what components make up a sarcomere?
Sarcomere: contractile unit of muscle
- myosin: thick filament
- actin: thin filaments
Process of muscle contraction
Motor neurons stimulate muscle contraction
Acetylcholine is released from motor neuron at
neuromuscular junction
Electrical impulse is transmitted along T tubules
Calcium is released from sarcoplasmic reticulum (modified smooth endoplasmic reticulum)
Calcium initiates chain of events that cause contraction
1.
Calcium is released from sarcoplasmic reticulum
2.
Calcium binds to troponin
3.
Troponin–tropomyosin complex shifts position
4.
Myosin binding site is exposed
5.
Myosin heads form cross-bridges with actin
6.
Actin filaments are pulled toward center of
sarcomere
7.
Sarcomere shortens
How does frequency of stimulation influence muscle contraction?
When the stimulation frequency was increased to the point in which muscle relaxation did not occur the amount of force progressively increased with each stimulus. When muscle twitches overlap, no muscles relax, and stimuli occurs one after another in a short amount of time, the muscle contraction is higher than if a single stand alone contraction had occurred; also known as wave summation.
