Structural support and movement Chapter 32

How do animals move? All animals ______________. Sometimes, they are capable of locomotion: _______________ __________________________________________________ As adults, even sessile animals (_________________________) usually _________________________. Mechanisms of locomotion: ______through water; ____through air; _____, _____, or _______along surfaces; or ________through soil and sediments. The same physical law governs all movement: For every action, there is an _________________________. For an animal to move in one direction, it must exert a force in the ______________direction. Ex. Jet propulsion by squids

How do animals move? _______and __________increase the amount of energy an animal must expend to move Some aquatic animals have a ____________________ that reduces the effects of friction Snails reduce friction by secreting a lubricating _____from their large foot Animals that walk or run minimize friction’s effects by ________________ __________ in contact with the ground Elevating the body above the ground and having only some feet contact the ground at any given time minimizes the effects of friction

How do animals move? ___________________plays a locomotive role in many animals Example: kangaroos have elastic material in their hind legs that facilitate hopping To fly, an animal must overcome ____________to become and stay airborne, and must also generate a force to propel itself ______________ Wing _______________is the key to flight The difference in air velocity across the two surfaces (top and bottom) of a wing creates lift, an upward force, that opposes gravity

What is a skeleton? Muscles bring about movement by interacting with a _________ Skeletons include: __________________________________ ___________________________________

Invertebrate Skeletons Hydrostatic skeleton: _________________________________ ____________________________ ____________________________ Exoskeleton: ________________________________________ ___________ Endoskeleton: _______________________ __________________________________

The Vertebrate Endoskeleton All vertebrates have endoskeletons: ______________________ __________________________________________________ The term “vertebrate” refers to the vertebral column (________) _______________, ________________________, __________________ Bony segments called _____________make up the backbone _______________________of cartilage between vertebrae act as shock absorbers

What are the functions of bone? Bone structure and function Bone formation and turnover Joints: Where bones meet

Bone structure and function ___________bones in an adult human’s skeleton They range in size from ___________bones as small as a grain of rice to the massive _______, which weighs about a kilogram. The femur and other bones of the arms and legs are ________. The ribs, the sternum, and most bones of the skull are ________. Still other bones, such as the carpals in the wrists, are _____and roughly _____________-ish in shape.

Bone structure and function Each bone is wrapped in a dense ___________________that has _________and ______________running through it. Bone tissue consists of ____________in a secreted extracellular matrix . The matrix is mostly ___________, a fibrous protein, hardened by _____________and _______________ions. A long bone such as a femur includes two types of bone tissue, _______________and ____________________.

Human femur

Bone structure and function Compact bone: ___________; makes up the shaft of long bones Spongy bone: ___________________with many internal spaces Red marrow: _____________________ Yellow marrow: ___________________

Bone formation and turnover Bone mass increases until about _____years of age Later in life, bone mass _____________________ Bone remodeling occurs throughout life, to repair _________________________caused by normal movement Parathyroid hormone, cortisol, estrogen, and testosterone alter _______________________ Osteoporosis: _______________________________________ __________________________________________________

Joints: Where bones meet A joint is an area __________________________________. Connective tissue holds bones securely in place at ___________ such as those between _____________________.

Joints: Where bones meet Pads or disks of cartilage connect bones at _______________, forming a flexible connection that allows a bit of movement. Cartilaginous joints connect __________ to one another and connect some ribs to the ______________.

Joints: Where bones meet Joints of the ____, __________, ________, ________, and ______are _____________, the most common type of joint. In a synovial joint, the ends of bones are covered with ___________ and enclosed in a _________________. Cords of dense connective tissue called __________ hold the bones of a synovial joint in place

Synovial joints

What are the functions of skeletal muscles? Skeletal muscles: function in intentional ____________, ______, and ___________________ Muscles can ________but cannot _______. To achieve the greatest range of motion, muscles work in ________, with the action of one muscle reversing action of another. https://www.youtube.com/watch?v=VCminz-X52I Tendon: ___________________________________________ __________________________________________________ Sphincter: _______________in a tubular organ or at a body opening (_______, _______, ___________)

What are the components of skeletal muscle? A muscle is enclosed within a sheath of ______________________ This tissue extends beyond the muscle as a ___________. Additional connective tissue encloses bundles of _______________ It contains many ______, which are positioned at its outer edges. The fiber also contains large numbers of __________, _______________ __________________. The bulk of the muscle fiber’s interior is filled with thousands of threadlike __________________ A myofibril consists of many identical ______________, called ________________, attached end to end. Each end of a sarcomere is delineated by a Z line, a mesh of cytoskeletal elements that attach the sarcomere to its neighbors. Sarcomere consists of two filaments: __________and ____________

What controls muscle contraction? Signals from ___________________ excite a motor neuron in the spinal cord The motor neuron communicates with __________muscle via the release of acetylcholine (ACh) Calcium is released from the __________________ , (a specialized endoplasmic reticulum that wraps around myofibrils and stores calcium ions.) which clears myosin binding sites on actin filaments ____________________________

What controls muscle contraction? Motor unit: _________________________________________ __________________________________________________ Muscle tension (_________________________________________________): depends on the number of contracting muscle fibers

How do muscles fuel their contractions? Energy-releasing pathways Types of muscle fibres

Energy releasing pathways (3) Muscles tap into their store of _______________________, a compound that can transfer a phosphate to ADP to form _____ Most of the ATP used by a muscle during prolonged, moderate activity is produced by ____________________. Glucose derived from glycogen stored in the muscle fuels this pathway for 5-10 minutes of contractions. Then, glucose and fatty acids delivered by the blood are broken down. Fatty acids are the main fuel for activities that last more than 30min. _______________________is the third source of ATP. Some pyruvate is converted to lactate by fermentation even in resting muscle, but the rate of fermentation increases during exercise. This pathway produces ATP less efficiently than aerobic respiration, but unlike aerobic respiration, it operates even when the oxygen level in a muscle is low.

Types of muscle fibres Red fibers: ____________________________________________________________________________________________________ Bright red color is due to myoglobin (___________________________) Fast fibers: ________________________________________________ White fibers: ____________________________________________________________________________________________________ Have no ______________ Fast or slow fibers