Unit 3.5The Skeletal &

Muscular Systems

Functions of BonesFunctions of Bones Support of the body

Protection of soft organs

Movement due to attached skeletal muscles

Storage of minerals and fats

Blood cell formation

Types of BonesTypes of BonesHuman skeleton has 206 bones

Microscopic Anatomy of BoneMicroscopic Anatomy of Bone

Types of Bone CellsTypes of Bone Cells

Osteocytes Mature bone cells

Osteoblasts Bone-forming cells

Osteoclasts Bone-destroying

cells

Stages in the Healing of a Bone Stages in the Healing of a Bone FractureFracture

The Axial SkeletonThe Axial Skeleton

Forms the longitudinal part of the body

Divided into three parts

Skull

Vertebral column

Bony thorax

The SkullThe Skull Two sets of bones

Cranium

Facial bones

Bones are joined by fused joints

Only the mandible is attached by a freely movable joint

The SkullThe Skull

Bones of the SkullBones of the Skull

The Fetal SkullThe Fetal Skull

The fetal skull is large compared to the infants total body length

Gaps allow the brain to grow over the next 2 years

The Vertebral ColumnThe Vertebral Column

Cervical vertebrae comprise the neck - 7

Thoracic vertebrae have ribs growing off of them - 12

Lumbar vertebrae comprise the lower back - 5

The Bony ThoraxThe Bony Thorax Forms a cage

to protect major organs

Made-up of three parts

Sternum

Ribs

Thoracic vertebrae

The Appendicular SkeletonThe Appendicular Skeleton

Limbs (appendages)

Pectoral girdle

Pelvic girdle

The Pectoral GirdleThe Pectoral Girdle Composed of two

bones

Clavicle – collarbone

Scapula – shoulder blade

Allow arms to have exceptionally free movement

Bones of the Upper LimbBones of the Upper Limb

The arm is formed by a single bone

Humorous

Bones of the Upper LimbBones of the Upper Limb

• The forearm has two bones

• Ulna – pinky side

• Radius – thumb side

Bones of the Upper LimbBones of the Upper Limb

The hand

Carpals – wrist

Metacarpals – palm

Phalanges – fingers

Bones of the Pelvic GirdleBones of the Pelvic Girdle

Hip bones

Composed of three pair of fused bones Ilium

Ischium

Pubic bone

Bones of the Lower LimbsBones of the Lower Limbs

The thigh has one bone

Femur – thigh bone

Bones of the Lower LimbsBones of the Lower Limbs

The leg has two bones

Tibia – front leg

Fibula – back leg

Bones of the Lower LimbsBones of the Lower Limbs

The foot

Tarsals – ankle

Metatarsals – sole

Phalanges – toes

The Muscular SystemThe Muscular System Three basic

muscle types are found in the body

Smooth muscle

Cardiac muscle

Skeletal muscle

Smooth Muscle CharacteristicsSmooth Muscle Characteristics

Involuntary – no conscious control

Found mainly in the walls of hollow organs

Also line blood vessels

Slow, sustained and tireless

Cardiac Muscle CharacteristicsCardiac Muscle Characteristics

Involuntary

Found only in the heart

Beat 100,000 times a day, 35 million times a year, and over 2.5 billion times in a lifetime

Skeletal Muscle CharacteristicsSkeletal Muscle Characteristics

Produce movement

Maintain posture

Stabilize joints

Generate heat

The Sliding Filament TheoryThe Sliding Filament Theory

Ventral Trunk MusclesVentral Trunk Muscles

Dorsal Trunk MusclesDorsal Trunk Muscles

Muscles of the Pelvis, Hip, and ThighMuscles of the Pelvis, Hip, and Thigh

Muscles of the Lower LegMuscles of the Lower Leg