Lectures 1-8 Flashcards
What is feedforward in homeostasis?
Anticipation of an event that will alter a controlled variable, leading to actions that minimize the effect.
Describe irregular bones.
Various shapes and functions; they often have foramina (holes).
What are the functions of the skeletal system?
Support, movement, protection, storage of minerals, and red blood cell formation.
What are movements in the sagittal plane?
Flexion and extension.
What are the two determinants of skeletal muscle force generation?
The number of muscle fibres recruited and the rate of muscle stimulation.
How is bone homeostasis maintained?
Balance between Osteoblast and Osteoclast activity, allowing constant bone formation and destruction.
Describe the pelvic girdle.
Made up of the two hip bones and the sacrum; supports weight-bearing.
What are sarcomeres and what do they contain?
Repeating units in myofibrils made of contractile proteins: actin (thin filaments) and myosin (thick filaments).
Identify the major bones of the skeleton, and understand why/how some are sexually dimorphic.
Major bones include the skull, vertebral column, rib cage, and limb bones. Sexual dimorphism is seen in the pelvis to accommodate childbirth in females.
What are the components of an osteon?
Central canal (with blood vessels and nerves), lamellae (cylinders of ECM), lacunae (for osteocytes), and canaliculi (channels for osteocytes).
What does the appendicular skeleton consist of and what is its function?
Consists of the limb bones; it is important for movement.
Which tissue can be divided into skeletal, cardiac, and smooth?
Muscle tissue.
What does the axial skeleton consist of and what is its function?
Consists of the skull, vertebral column, and rib cage; it protects vital organs.
Describe the microscopic structure of bones.
Compact bone has osteons with central canals, lamellae, lacunae, and canaliculi; cancellous bone has trabeculae with marrow and osteocytes.
Describe the structure and function of the skull.
Made up of the cranium and facial bones; protects the brain and supports sensory organs.
What is inversion?
Turning the sole of the foot towards the midline.
What are movements in the coronal plane?
Abduction and adduction.
What responses are coordinated by the Heat-Gain centre when body temperature lowers?
Behavioral changes, vasoconstriction, reduced sweat production, shivering, and goosebumps.
What happens if there is an imbalance of water and solute concentrations across the cell membrane?
Water will move to balance the concentrations, affecting cell size and integrity.
What is osmosis?
Movement of water across a membrane to equalize solute concentration.
Define terms used to describe spatial and positional relationships of structures.
Anterior/posterior, superior/inferior, medial/lateral, proximal/distal, superficial/deep.
Describe the gross structure of bones and explain how they reflect their functions.
Compact bone is strong for force transmission; cancellous bone is light and spongy for shock absorption.
How does the length-tension relationship affect muscle strength?
Each muscle has an optimal length where it is strongest, with changing overlap between actin and myosin filaments affecting strength.
What is DFCT, and what are its characteristics?
Dense Fibrous Connective Tissue; contains fibroblasts, collagen, and some elastin, resists tension, and has little vascularity.