Anatomy Unit 3 Study Guide

Front 1

Identify the components of the integumentary system.

Back 1

The integumentary system is the most extensive of the organ systems in the human body. It has a number of roles, including regulating body temperature, excretion, protecting internal structures, vitamin D production and keeping microorganisms out of the body, reports Body Guide. The system is also integral in recognizing external stimuli (heat and cold, for example). It is made up several diverse components.

Front 2

Compare and contrast the layers of skin.

Back 2

Epidermis, "epi" coming from the Greek meaning "over" or "upon", is the outermost layer of the skin. It forms the waterproof, protective wrap over the body's surface and is made up of stratified squamous epithelium with an underlying basal lamina.[citation needed]

The epidermis contains no blood vessels, and cells in the deepest layers are nourished by diffusion from blood capillaries extending to the upper layers of the dermis. The main type of cells which make up the epidermis are Merkel cells, keratinocytes, with melanocytes and Langerhans cells also present. The epidermis can be further subdivided into the following strata (beginning with the outermost layer): corneum, lucidum (only in palms of hands and bottoms of feet), granulosum, spinosum, basale. Cells are formed through mitosis at the basale layer. The dermis is the layer of skin beneath the epidermis that consists of connective tissue and cushions the body from stress and strain. The dermis is tightly connected to the epidermis by a basement membrane. It also harbors many Mechanoreceptors (nerve endings) that provide the sense of touch and heat. It contains the hair follicles, sweat glands, sebaceous glands, apocrine glands, lymphatic vessels and blood vessels. The blood vessels in the dermis provide nourishment and waste removal from its own cells as well as from the Stratum basale of the epidermis.The papillary region is composed of loose areolar connective tissue. This is named for its fingerlike projections called papillae, that extend toward the epidermis. The papillae provide the dermis with a "bumpy" surface that interdigitates with the epidermis, strengthening the connection between the two layers of skin. The reticular region lies deep in the papillary region and is usually much thicker. It is composed of dense irregular connective tissue, and receives its name from the dense concentration of collagenous, elastic, and reticular fibres that weave throughout it. These protein fibres give the dermis its properties of strength, extensibility, and elasticity. Also located within the reticular region are the roots of the hair, sebaceous glands, sweat glands, receptors, nails, and blood vessels. The hypodermis is not part of the skin, and lies below the dermis. Its purpose is to attach the skin to underlying bone and muscle as well as supplying it with blood vessels and nerves. It consists of loose connective tissue and elastin. The main cell types are fibroblasts, macrophages and adipocytes (the hypodermis contains 50% of body fat). Fat serves as padding and insulation for the body. Another name for the hypodermis is the subcutaneous tissue.

Front 3

Explain how the components of the integumentary system protects the body.

Back 3

The components protect the body because it acts as a covering for the internal organs. The skin keeps out harmful germs and bacteria as well as helps keep the body healthy by regulating temperature. If the body is overheated, then the body will sweat to lower the overall body temperature. If the body is too cold then the skin will form goose bumps to try and conceal the heat. Skin also protects the body from harmful ultraviolet rays.

Front 4

Identify the bones of the skeletal system and their role in protection, support, and movement.

Back 4

The skeletal system comprises of 206 bones and provides four basic functions:

•Support for tissues and muscle
•Protection for vital organs
•Movement through bones and attached muscles
•Storage for minerals and immature blood cells
In the skull (22):

Cranial bones:

frontal bone
parietal bone (2)
temporal bone (2)
occipital bone
sphenoid bone
ethmoid bone

Facial bones:

zygomatic bone (2)
superior and 7. inferior maxilla
nasal bone (2)
mandible
palatine bone (2)
lacrimal bone (2)
vomer bone
inferior nasal conchae (2)

In the middle ears (6):

malleus (2)
incus (2)
stapes (2)

In the throat (1):

hyoid bone

In the shoulder girdle (4):

clavicle or collarbone (2)
scapula or shoulder blade (2)

In the thorax (25):

sternum
ribs (2 x 12)

In the vertebral column (24):

cervical vertebrae (7) incl. atlas & axis
lumbar vertebrae (5)
thoracic vertebrae (12)

In the arms (6):

humerus (2)
condyles of humerus
ulna (2)
radius (2)
head of radius

In the hands (54):

Wrist (carpal) bones:
scaphoid bone (2)
navicular bone (2)
lunate bone (2)
triquetral bone (2)
pisiform bone (2)
Trapezium (bone) (2)
trapezoid bone (2)
capitate bone (2)
hamate bone (2)
Palm or metacarpal bones:
metacarpal bones (5 × 2)
Finger bones or phalanges:
proximal phalanges (5 × 2)
intermediate phalanges (4 × 2)
distal phalanges (5 × 2)

In the pelvis (4):

ossa coxae (hip bones or innominate bones) (2)
sacrum
coccyx

In the legs (8):

head and 18. shaft of femur (2)
greater trochanter of femur
condyles of femur
patella (2)
shaft and 24. tuberosity of tibia (2)
fibula (2)

In the feet (52):

Ankle (tarsal) bones:
calcaneus (heel bone) (2)
talus (2)
navicular bone (2)
medial cuneiform bone (2)
intermediate cuneiform bone (2)
lateral cuneiform bone (2)
cuboid bone (2)
Instep bones:
metatarsal bone (5 × 2)

Toe bones:

proximal phalanges (5 × 2)
intermediate phalanges (4 × 2)
distal phalanges (5 × 2)

Front 5

Explain how ossification and resorption lead to homeostasis of bone.

Back 5

The breaking down of bone during the ossification process helps maintain homeostasis because this process breaks down bone, causing calcium ions to be released into the blood stream, helping make sure that the calcium levels are balanced. Resorption is the process of absorbing the calcium, which contributes to maintaining homeostasis.

Front 6

Classify bones as long, short, irregular, flat or sesamoid.

Back 6

Long bones are some of the longest bones in the body, such as the Femur, Humerus and Tibia but are also some of the smallest including the Metacarpals, Metatarsals and Phalanges. The classification of a long bone includes having a body which is longer than it is wide, with growth plates (epiphysis) at either end, having a hard outer surface of compact bone and a spongy inner known an cancellous bone containing bone marrow. Both ends of the bone are covered in hyaline cartilage to help protect the bone and aid shock absorbtion.

Short bones are defined as being approximately as wide as they are long and have a primary function of providing support and stability with little movement. Examples of short bones are the Carpals and Tarsals - the wrist and foot bones. They consist of only a thin layer of compact, hard bone with cancellous bone on the inside along with relatively large amounts of bone marrow.

Flat bones are as they sound, strong, flat plates of bone with the main function of providing protection to the bodies vital organs and being a base for muscular attachment. The classic example of a flat bone is the Scapula (shoulder blade). The Sternum (breast bone), Cranium (skull), os coxae (hip bone) Pelvis and Ribs are also classified as flat bones. Anterior and posterior surfaces are formed of compact bone to provide strength for protection with the centre consisiting of cancellous (spongy) bone and varying amounts of bone marrow. In adults, the highest number of red blood cells are formed in flat bones.

These are bones in the body which do not fall into any other category, due to their non-uniform shape. Good examples of these are the Vertebrae, Sacrum and Mandible (lower jaw). They primarily consist of cancellous bone, with a thin outer layer of compact bone.

Sesamoid bones are usually short or irregular bones, imbedded in a tendon. The most obvious example of this is the Patella (knee cap) which sits within the Patella or Quadriceps tendon. Other sesamoid bones are the Pisiform (smallest of the Carpals) and the two small bones at the base of the 1st Metatarsal. Sesamoid bones are usually present in a tendon where it passes over a joint which serves to protect the tendon.

Front 7

Explain how the structure of a joint determines its function.

Back 7

fibrous joint - joined by dense irregular connective tissue that is rich in collagen fibers

cartilaginous joint - joined by cartilage

synovial joint - not directly joined - the bones have a synovial cavity and are united by the dense irregular connective tissue that forms the articular capsule that is normally associated with accessory ligaments

Front 8

Classify the movements at joints as gliding, rotation abduction, adduction, ect.

Back 8

Flexion is a movement, generally in the sagittal plane, that decreases the angle of the joint and brings two bones together. Flexion is typically a type of hinge joint joint (bending the knee or elbow) but it is also common at ball-and-socket joints (bending forward at the hips)

Extension is the opposite of flexion and it increases the angle or distance between two bones or parts of the body (straightening the knee or elbow). If the extension is greater than 180 deg then it is a hyperextension.

Rotation ismovement of a bone around its longitudinal axis. It is a common movement of the ball-and-socket joints and describes the movement of the atlas around the dens of the axis (shaking your head "no")

Abduction is moving a limb away (generally on the frontal plane) from the midline, or median plane of the body. This also applies to the movement of fingers or toes apart from each other.

Adduction is the opposite of abduction, so it is the movement of a limb toward the body midline.

Circumduction is a combination of flexion, extension, abduction, and adduction commonly seen in ball-and-socket joints such as the shoulder. The proximal end is stationary and its distal end moves in a circle.

Front 9

Compare and contrast the 3 main types of muscle tissue.

Back 9

Skeletal muscle or "voluntary muscle" is anchored by tendons (or by aponeuroses at a few places) to bone and is used to effect skeletal movement such as locomotion and in maintaining posture. Though this postural control is generally maintained as a subconscious reflex, the muscles responsible react to conscious control like non-postural muscles. An average adult male is made up of 42% of skeletal muscle and an average adult female is made up of 36% (as a percentage of body mass).

Smooth muscle or "involuntary muscle" is found within the walls of organs and structures such as the esophagus, stomach, intestines, bronchi, uterus, urethra, bladder, blood vessels, and the arrector pili in the skin (in which it controls erection of body hair). Unlike skeletal muscle, smooth muscle is not under conscious control.

Cardiac muscle is also an "involuntary muscle" but is more akin in structure to skeletal muscle, and is found only in the heart.

Front 10

Discuss the structure of a sarcomere.

Back 10

A sarcomere (Greek sárx = "flesh", méros = "part") is the basic unit of a muscle. Muscles are composed of tubular muscle cells (myocytes or myofibers). Muscle cells are composed of tubular myofibrils. Myofibrils are composed of repeating sections of sarcomeres, which appear under the microscope as dark and light bands. Sarcomeres are composed of long, fibrous proteins that slide past each other when the muscles contract and relax. Two of the important proteins are myosin, which forms the thick filament, and actin, which forms the thin filament. Myosin has a long, fibrous tail and a globular head, which binds to actin. The myosin head also binds to ATP, which is the source of energy for muscle movement. Myosin can only bind to actin when the binding sites on actin are exposed by calcium ions. Actin molecules are bound to the Z line, which forms the borders of the sarcomere. Other bands appear when the sarcomere is relaxed.

Front 11

Explain how muscles contract using the sliding filament mechanism.

Back 11

The process of a muscle contracting can be divided into 5 sections:

1.A nervous impulse arrives at the neuromuscular junction, which causes a release of a chemical called Acetylcholine. The presence of Acetylcholine causes the depolarisation of the motor end plate which travels throughout the muscle by the transverse tubules, causing Calcium (Ca+) to be released from the sarcoplasmic reticulum.

2.In the presence of high concentrations of Ca+, the Ca+ binds to Troponin, changing its shape and so moving Tropomyosin from the active site of the Actin. The Myosin filaments can now attach to the Actin, forming a cross-bridge.

3.The breakdown of ATP releases energy which enables the Myosin to pull the Actin filaments inwards and so shortening the muscle. This occurs along the entire length of every myofibril in the muscle cell.

4.The Myosin detaches from the Actin and the cross-bridge is broken when an ATP molecule binds to the Myosin head. When the ATP is then broken down the Myosin head can again attach to an Actin binding site further along the Actin filament and repeat the 'power stroke'. This repeated pulling of the Actin over the myosin is often known as the ratchet mechanism.

5.This process of muscular contraction can last for as long as there is adequate ATP and Ca+ stores. Once the impulse stops the Ca+ is pumped back to the Sarcoplasmic Reticulum and the Actin returns to its resting position causing the muscle to lengthen and relax.

Front 12

Identify some common muscle pairs.

Back 12

Biceps/ triceps
Pectorals/latissimus dorsi
Anterior deltoids/posterior deltoids
Trapezius/deltoids
Abdominals/spinal erectors
Left and right external obliques
Quadriceps/hamstrings
Shins/calves
Forearm flexors/extensors