Anatomy of the body Flashcards
There are two types of skeleton - the appendicular skeleton and the axial skeleton - what is the difference between the two?
- Appendicular skeleton comprises:
- bones of lower and upper limbs i.e. radius, ulna etc. - Axial skeleton comprises:
- bones of the skull
- vertebral column
- ribs
- sternum
Does cartilage have blood supply, innervation or lymphatic supply?
No. Cartilage is avascular. It is nourished by diffusion.
How many types of cartilage are there?
- hyaline (contains moderate amount of collagen) - found in articular surfaces of bones
- elastic (matrix comprises collagen fibres + many elastic fibres)
- Fibrocartilage (matrix contains few cells and ground substance + lots of collagen fibres) - found in intervertebral discs
How many types of bone are there? What are they?
There exist 2 types of bones:
- cancellous (spongy or trabecular)
- compact (cortical)
How can we classify bones by morphology?
- long bones (tubular)
- short bones (cuboidal)
- flat bones
- irregular bones
- sesamoid bones (round or oval)
Cartilage has no blood supply, lymph supply or innervation. Is the same true for bone?
No. Bone is vascular and innervated.
Where does a bone receive blood supply from?
A bone receives blood supply from nutrient arteries, these are vessels that branch off nearby arteries.
Typically, a bone receives blood supply from one artery.
What parts of a bone receive blood supply from an artery?
- bone marrow
- compact bone (trabecular)
- spongy bone (cancellous)
Bones are externally surrounded by a layer of fibrous connective tissue membrane called the _____?
Periosteum
How are bone and periosteum different?
Periosteum has sensory nerve fibres vs bone, which does not
Where do all bones originate from?
All bones originate from the mesenchyme by:
1. ossification between membranes
or
- endochondral ossification (cartilaginous models of bones form from mesenchyme and undergo ossification)
Bone marrow contains two types of stem cells. What are they?
- Hematopoietic stem cells - these form blood cells i.e. platelets, RBCs, WBCs
- Mesenchymal stem cells - these differentiate into cartilage, bone and muscle
What is a joint? How many categories are there?
A joint is where two bones meet.
There are two categories of joints:
- synovial joints
- solid joints
What is the difference between a solid joint and a synovial joint?
Synovial joints separate bones by a cavity whereas solid joints connect the bones by connective tissue (and there is no cavity)
What are the features of a synovial joint?
- hyaline cartilage covering the articulating surface(s) of the bones
- presence of joint capsule (comprises inner synovial membrane and outer fibrous membrane(
What are the typical features of a synovial joint?
- fibrous capsule
- synovial membrane
- lubricating synovial fluid within joint cavity
- articular cartilage which covers the surface of each opposing bone
Bone is made up of 3 components, what are they?
- organic matrix
- inorganic mineral content
- water
The organic matrix of bone makes up ca. 1/4 of the total bone weight. This is further made of collagen fibres and proteoglycans. What is the percentage composition of each?
95% is collagen
5 % is proteoglycan (these are found between the collagen fibres, as they support them)
Sarcomeres are the basic structural units of muscles. What is the equivalent for bone?
Osteon / haversian system.
Where is spongy (cancellous) bone found?
At the epiphyses of long bones (i.e. femur), vertebral bones, flat bones (pelvis)
Does the periosteum cover the entire bone?
The periosteum covers most of the bone except the ends. The ends of a bone are covered with hyaline articular cartilage)
In longer bones, a central cavity known as the medullary cavity is found. This is enclosed by a membrane called the __________?
Endosteum
Red bone marrow is important for the synthesis of RBCs, WBCs and platelets. The location of this type of marrow differs in adults and children. How is this so?
Red bone marrow is found in medullary cavity of long bones in children, however in adults this is replaced by yellow fatty marrow.
In adults, the red bone marrow is found in flat bones i.e. the sternum, pelvis etc.
There are two main categories of joints - solid and synovial. The solid joints can be further categorised into ________ and __________.
Fibrous and cartilaginous
Two classes of joints exist: synovial and solid. Solid joints can be further categorised into fibrous joints and cartilaginous joints. The fibrous joints can be further subcategorised into 3 more divisions, what are these?
Fibrous joints can be categorised into:
- sutures (found only in the skull)
- gomphosis
- syndesmosis
Two classes of joints exist: synovial and solid. Solid joints can be further categorised into fibrous joints and cartilaginous joints. The cartilaginous joints can be further subcategorised into 2 more divisions, what are these?
- synchondrosis
2. symphysis
What is a syndesmosis? What are some examples?
A type of fibrous joint (belonging to the solid joint class) that links adjacent bones with a ligament.
Examples are the interosseous membrane between the radius and ulna
What is a synchondrosis?
A type of cartilaginous joint belonging to the class of solid joints that
What is a synchondrosis? Give an example.
A type of cartilaginous joint belonging to the class of solid joints, where two ossification centres in a developing bone remain separated by a layer of cartilage.
An example of a synchondrosis joint is between the growth plate in the head and shaft of a developing bone.
What is a symphysis?
A type of cartilaginous joint (of the solid joint class) that connects two separate bones by cartilage.
