Exam 1 Flashcards
The word anatomy means?
Greek for “to cut apart”
Cytology ?
The study of cells
Gross anatomy is?
structures visible to the unaided eye
Metabolism
Various chemical reactions tht organisms carry out are collectively
Homeostasis?
Refers to an organism’s ability to regulate its internal environment despite changes in the external environment
A cell
Smallest structural unit that exhibits the characteristics of living things
The skeletal system
Provides support and protection as well as hemopoiesis
What is the function of cartilage located in the epiphyseal plate?
Site of bone elongation and growth
The knobby region at the end of long bone farthest
Distal epiphysis
The periosteum is anchored to the bone by collagen fibers called?
Perforating fibers
Intersistial growth of cartilage?
increases its length and occurs internally
An osteoclats looks like?
ruffled border and multipe nuclei
During appositional growth of cartilage, cells that produce the matrix?
Chondroblasts
What affects osteoblasts and osteoclasts activity ?
gravity, mechanical stress, blood calcium, calcitonin + parathyroid hormones
Endochondral ossification begins with ?
hyaline cartilage model
Steps of endochondral ossification ?
- Cartilage model develops
- Cartilage calcifies and a bone collar forms
- offification center forms in the diaphysis
- ossification centers form in the epiphyses
- Bone replaces cartilage
- Epiphyseal plates ossify
Mechanical stress is detected by?
Osteocytes - then to osteoblast to increase synthesis of osteoid
What hormone inhibits bone growth?
Parathyroid hormone
What vitman synthesised collagen?
Vitaman C
Rickets - overproduction and deficient calcification of osteoid tissue - lack of ?
Vitamin D
Calcitriol ?
stimulates absorption of calcium in small intestine
Which hormone has a significant effect on blood calcium levels?
Parathyroid hormone
components of skeletal systems?
Compact bone, trabecular bone, cartilage, ligaments
What is the process of bone repair?
- Fracture hematoma forms
- fibrocartilaginous callus forms
- Bony callus forms
- bone is remodeled
OSteoporosis
Bones are porous and thin but bone composition is normal
Osteomalacia
Bone formed is poorly mineralized and soft. Deforms on weight bearing
Paget’s disease
Excessive and haphazard bone deposit and resorption
Greenstick
An incomplete fracture of the bone without actual separation of the parts
Comminuted
Bone fragments into many pieces
Spiral fracture
Common sports fracture resulting from a twisting force
Epiphyseal plate
Area where bone longitudinal growth takes place
Inramembranous ossification
Bone develops from a fibrous membrane
Appoistional growth
The growth pattern of bone in which matrix is laid down on the surface
Epiphyseal line
The appearance of this structure signals the end of bone growth
Chondrocytes
The cells responsible for the early stages of endochondral ossification
Compact bone
Adapted to support weight and withstand torsion stresses
Yellow bone marrow contains ?
fat
Which cell secretes the matrix of bone?
Osteoblast
What tissue is the forerunner of long bones ?
Hyaline cartilage
what can a deficiency of growth hormone during bone formation cause?
Decreased epiphyseal plate activity
A fracture in the shaft of a bone would be a break in the
diaphysis
Ossification of the ends of long bones
is produced by secondary ossification centers
Which structure allows the diaphysis of the bone to increase in length until early childhood
Epiphyseal plate
Which of the following is the single most important stimulus for epiphyseal plate activity
during infancy and childhood
growth hormone
The periosteum is secured to the underlying bone b
Perforating fibers (sharpeys)
The resilience of bone is thought to come from which of the following?
sacrificial bonds in or between collagen molecules
For intramembranous ossification to take place, which of the following is necessary?
Ossification centers form in the fibrous connective tissue membrane
The process of bones increasing in thickness?
Appositional growth
Bones are constantly undergoing resorption (breaking bone down) for various reasons.
Which of the following cells accomplishes this process
Osteoclast
Which hormone increases osteoclast activity to release more calcium ions into the
bloodstream
PTH
Wolff’s law is concerned with
The thickness and shape of a bone being dependent on stresses placed upon it
Cranial bones develop?
within fibrous membranes
in humans, the effect of the hormone calcitonin is to
emporarily decrease blood calcium levels when administered in large doses
Cartilage grows in two ways, appositional and interstitial. What is appositional growth?
the secretion of new matrix against the external face of existing cartilage
Which of the following statements best describes interstitial growth of cartilage?
Chondrocytes in the lacunae divide and secrete matrix, allowing the cartilage to grow from
within.
In the epiphyseal plate, cartilage grows
by pushing the epiphysis away from the diaphysis
Spongy bone contains
trabeculae
Ossification (Osteogenesis) is the process of
bone formation
Lengthwise, long bone growth during infancy and youth is exclusively through
interstitial growth of the epiphyseal plates
Growth of bones is controlled by a symphony of hormones. Which hormone is of greatest
importance for bone growth during infancy and childhood?
growth hormone
In some cases, the epiphyseal plate of the long bones of children closes too early. What
might be the cause?
elevated levels of sex hormones
Prevention of osteoporosis includes adequate intake of
Calcium and Vit D
What tissue forms the model of endochondral ossification
Cartilage
the pubic symphysis connects the two hip bones anteriorly and provides a little movement
during childbirth. Choose the most appropriate tissue for this structure that is subjected to both
pressure and stretch
fibrocartilage
structures that most directly provide nutrients and remove wastes from osteocytes
in compact bone.
Canaliculi
When an osteoblast becomes completely surrounded by its own matrix secretions it is
referred to as an
Osteocyte
