Anatomical directions, body cavities, and ossification Flashcards
What is the median plane?
- splits animal into exact left and right halves
- nose to tail
what is the sagittal plane?
- splits animal into left and right halves without exact symmetry
- nose to tail but deviates left to right
what is the dorsal plane?
- splits animal into top and bottom halves
- top half
what is the transverse plane?
-splits animal into cranial and caudal halves
what is protraction?
limb forward
what is retraction?
limb backwards
what is adduction?
limb towards midline
what is abduction?
limb away from midline
what is flexion?
reduce smallest joint angle
what is extension?
increase the angle
what is overextension?
beyond 180 degrees
what is pronation?
palms downwards
what is supination?
palms upwards
what is circumduction?
limb extremity moves in a circle
what is gliding?
one articular surface slides over another
what is a ligament?
dense connective tissue band - bone to bone
what is a tendon?
dense connective tissue - muscle to bone
what is in the thorax cavity?
- vagus nerve - aorta - vena cava - thymus - thoracic duct - lungs - heart - distal trachea - bronchi - oesophagus
what is in the abdominal cavity?
- stomach - liver - spleen - gall bladder - pancreas - small intestine - caecum - large intestine - colon - rectum - bladder - ureters - urethra - kidneys - uterus - ovaries
what is the lining of the walls of any cavity called?
parietal
what is the lining of the organs of any cavity called?
visceral
true or false: parietal and visceral linings are one continuous sheet of serious tissue
true
what is the term that relates to body cavity and organ lining in the thoracic cavity?
pleura
what is the tissue that lines the walls of the thoracic cavity called?
parietal pleura
what is the tissue that lines the organs of the thoracic cavity called?
visceral pleura
what is the term that relates to body cavity and organ lining in the abdominal cavity?
peritoneum
what is the tissue that lines the walls of the abdominal cavity called?
parietal peritoneum
what is the tissue that lines the organs of the abdominal cavity called?
visceral peritoneum
what allows lubrication and organs to glide other each other in the cavities?
serous fluid
what can the change in consistency or decreased production of the serous fluid cause?
adhesions
what is the mediastinum?
the cavity between the left and right lungs which contains the heart and aorta
what is the diaphragm?
it separates the thoracic and abdominal cavities
what is the hole in the diaphragm that allows for the aorta to pass through called?
aortic hiatus
what is the hole in the diaphragm that allows the oesophagus to pass through called?
oesophageal hiatus
what is the hole in the diaphragm that allows the vena cava to pass through called?
caval foramen
what are the thorax boundaries for these anatomical directions?
- dorsal
- ventral
- cranial
- caudal
- lateral
- dorsal - thoracic vertebrae
- ventral - sternum
- cranial - thoracic inlet
- caudal - diaphragm
- lateral - ribs
what are the abdomen boundaries for these anatomical directions?
- dorsal
- ventral
- cranial
- caudal
- lateral
- dorsal -lumbar vertebrae
- ventral - abdominal muscles
- cranial - diaphragm
- caudal - pelvic inlet
- lateral - abdominal muscles
what are the pelvic boundaries for these anatomical directions?
- dorsal
- ventral
- cranial
- caudal
- lateral
- dorsal - sacrum
- ventral - pelvic bones
- cranial - pelvic inlet
- caudal - pelvic diaphragm
- lateral - pelvic bones
what are the functions of the skeletal system?
- support
- locomotion
- mineral storage
- haematopoiesis
- protection
how can joints be classified?
by the type of tissue they were made from (fibrous, cartilaginous, or synovial) or type of movement they allow
how does the skeletal system provide support?
holds animal in position and provides scaffold for attachment of muscles, tissues, skin and organs
how does the skeletal system provide locomotion?
provides an attachment for muscles
how does the skeletal system provide mineral storage?
- stores essential minerals, calcium and phosphorus which gives bones strength and rigidity
- allows them to dissolve minerals into the blood
how does the skeletal system provide haematopoiesis?
- (formation of blood cells)
- haematopoietic tissue forming the bone marrow manufactures erythrocytes (rbc) , platelets, and granular leukocytes (wbc)
- production is dependent on demand
how does the skeletal system provide protection of internal organs?
- vertebrae, ribs and sternum form a cage which encloses organs
- skull protects brain and stem of spinal cord
- eyeball protected in a socket
what are the three principles found in bones?
- osteoblasts (immature cells which can synthesize osteoid)
- osteocytes (mature cells which maintain bone structure)
- osteoclasts (cells which can breakdown and re-model bone
what are the two types of bone structure?
compact bone and cancellous bone
what does bone consist of?
- cells
- collagen
- glyco-proteins
- calcium
what is compact bone?
- found in the cortex of long bones
- found in areas prone to stress
- lamellae are arranged around the haversian canal (contains blood vessels, nerves, and loose connective tissue)
what are gaps in lamellae called and what do the gaps contain?
lacunae, they contain osteocytes
what are concentric circles of matrix in compact bone called?
lamellae
what does the haversian canal contain?
blood vessels, nerves, and loose connective tissues
what is cancellous bone?
- commonly found in vertebrae, flat bones and at the end of long bones
- comprises of trabeculae with spaces in between which decreases strength
what is trabeculae?
interconnected bars of bone
what are the 5 types of bones?
- long
- short
- flat
- irregular
- sesamoid
what are some examples of long bones?
- humerus
- radius
- fibula
- femur
- tibia
long bones: what are epiphyses?
the two ends of the bone, composed of cancellous, covered with a thin layer of compact
long bones: what are diaphysis?
shaft of the bone, composed of tough cylinders of compact bone
long bones: what are metaphysis?
region where the diaphysis meets the epiphysis
long bones: what shaft is filled with bone marrow?
medullary cavity
long bones: what is the articular cartilage?
a thin layer of hyaline cartilage covering both ends of the epiphyses
long bones: what is the periosteum?
- a sheath of tough connective tissue covering the non-articular surface of all bones
- essential for bone growth, repair and nutrition
- outer and inner layer
long bones: what is the endosteum?
- consisting of a layer of osteoblasts that line the medullary cavity
what are short bones?
- consist of a core of cancellous bone covered by a thin layer of compact bone
- no medullary cavity
- examples - carpal and tarsal
what are irregular bones?
- consist of two layers of compact bone surrounding cancellous bone
- examples - vertebrae, some skull bones
what are flat bones?
- have no medullary cavity
- composed of two layers of hard compact bone covering cancellous bone in the centre
- examples: skull, scapula, pelvis
what are sesamoid bones?
- irregular in shape
- smooth, small bones formed in tendons
- run over an underlying bony prominence
what is ossification?
the process by which bone forms in the body
what are the the two types of ossification?
- endochondral ossification
- intramenbranous ossification
what is endochondral ossification?
- the replacement of cartilage by bone during fetal development
- initial hyaline cartilage is gradually replaced by osteocytes and calcium
how can you spot a growth plate fracture on an x-ray?
- widened black space
- common in young animals
what is the recommended range for dietary calcium in large-breed puppies?
0.8%-1.2%
what ratio should calcium and phosphorus be provided in?
1.1:1 - 2:1
what is intramembranous ossification?
- where bone is laid down to replace fibrous connective tissue
- occurs in the development of bones in the skull, maxilla, and mandible
what is red bone marrow?
- spongy bone of vertebrae, ribs, short and flat bone
- production of RBC and some WBC
what is yellow bone marrow?
- mainly made up of fat
- found in long bones
what is cartilage?
- mainly made up of collagen produced by chondrocytes
- similar to bone but without mineralisation so is softer
- three types of cartilage
1) hyaline
2) fibrocartilage
3) elastic
what are the three types of skull?
- dolichocephalic - long nose
- mesocephalic - normal
- brachycephalic - flat nose and mouth, wide eyes
what is the cranium?
the caudal part of the skull provides a bony case for the brain
what is the cranium made up of?
- parietal
- temporal
- frontal
- occiptal
- sphenoid
- sagittal crest
- zygomatic arch
- lacrimal
what does the parietal bone (cranium) do?
- forms dorsal and lateral wall of cranium
what does the temporal bone (cranium) do?
- tympanic bulla houses middle ear
what is the frontal bone (cranium) ?
- forehead and frontal sinuses
what is the occiptal (cranium) bone?
- lies at the base of the skull
- foramen magnum where spinal cord passes
- occiptal condyles attach to the first cervical vertebrae
what is the sphenoid bone (cranium) ?
ventral aspect of the skull
what is the sagittal crest bone (cranium) ?
ridge of bone on the dorsal midline surface
what is the zygomatic arch (cranium)?
cheek bone
what is the lacrimal (cranium)?
lies at the base of the orbit