BIO 243 Exam 2 Questions with Correct Answers Latest Update 2025/2026
major functions of skeletal system - Answers encasement and protection of organs, support,
movement, hematopoiesis, calcium and phosphate homeostasis
structure of skeletal system - Answers Made up of osseous tissue + bone marrow
Very vascular and innervated by sensory neurons
Periosteum layer - Answers outermost layer, dense irregular tissue
compact bone - Answers dense, hard bone that provides resistance to compression
spongy bone - Answers innermost layer, contains marrow
nutrient foramen - Answers small opening in the middle of the external surface of the diaphysis,
through which an artery enters the bone to provide nourishment
nutrient canal - Answers Small tubelike passageway through bone that contains blood vessels
and nerves, exit point for nutrient vessels
nutrient vein - Answers sends CO2-rich blood away from the bone tissue
nutrient artery - Answers brings oxygenated blood to the bone tissue
Epiphysis - Answers rounded ends of long bones, contains the most spongy bone/marrow
Diaphysis - Answers long shaft of long bones, thick layer of compact bone with a small amount
of spongy bone/marrow inside
Metaphysis - Answers halfway point between epiphysis and diaphysis, site of bone growth
long bone - Answers longer than they are wide
EXAMPLES metatarsals, humerus, femur
short bone - Answers equally long and wide
EXAMPLES carpals, tarsals
flat bone - Answers thin and often rounded
EXAMPLES skull, sternum
Sesamoid bone - Answers small, flat, oval-shaped; suspended in tendons
EXAMPLE patella
Irregular - Answers bones that do not fit in the 4 above categories
, EXAMPLE vertebrae
Depressions - Answers -allow vessels and nerves to run along a bone, allow two bones to
articulate
-Facet, fossa, fovea, groove
Openings - Answers -holes in the bone for vessels and nerves
-Meatus (canal), fissure, foramen
Projections - Answers -bony extensions that serve as attachment sites for muscles, tendons,
ligaments, and some joints
-Condyle, crest, head, tubercle/tuberosity, epicondyle, process, spine, protuberance, line
Marrow cells - Answers hematopoietic stem cells produce blood cells, also includes adipocytes
Osteoblasts - Answers build new bone (ossification)
Osteoclasts - Answers break down bone
Osteocytes - Answers mature bone cells
Intramembranous Ossification - Answers Cranial Vault ■ Maxilla/Mandible ■ Clavicles
Endochondral Ossification - Answers Skull base ■ Vertebrae ■ Pelvis ■ Long Bones
For both types of ossification, the first immature bones formed are called.. - Answers primary
bones
ALSO
Consists of irregularly arranged collagen bundles, osteocytes, and some inorganic matrix
Eventually resorbed by osteoclast activity and replaced with.. - Answers mature secondary bone
+
fully formed lamellae, regularly arranged collagen bundles, much more inorganic matrix, and is
therefore a much stronger type of bone
Growth in long bones occurs at - Answers epiphyseal plate
Appositional growth - Answers process by which bones grow in width or thickness
Break down bone to release calcium in times of need or as a result of fracture/normal wear and
tear? - Answers Osteoclasts
major functions of skeletal system - Answers encasement and protection of organs, support,
movement, hematopoiesis, calcium and phosphate homeostasis
structure of skeletal system - Answers Made up of osseous tissue + bone marrow
Very vascular and innervated by sensory neurons
Periosteum layer - Answers outermost layer, dense irregular tissue
compact bone - Answers dense, hard bone that provides resistance to compression
spongy bone - Answers innermost layer, contains marrow
nutrient foramen - Answers small opening in the middle of the external surface of the diaphysis,
through which an artery enters the bone to provide nourishment
nutrient canal - Answers Small tubelike passageway through bone that contains blood vessels
and nerves, exit point for nutrient vessels
nutrient vein - Answers sends CO2-rich blood away from the bone tissue
nutrient artery - Answers brings oxygenated blood to the bone tissue
Epiphysis - Answers rounded ends of long bones, contains the most spongy bone/marrow
Diaphysis - Answers long shaft of long bones, thick layer of compact bone with a small amount
of spongy bone/marrow inside
Metaphysis - Answers halfway point between epiphysis and diaphysis, site of bone growth
long bone - Answers longer than they are wide
EXAMPLES metatarsals, humerus, femur
short bone - Answers equally long and wide
EXAMPLES carpals, tarsals
flat bone - Answers thin and often rounded
EXAMPLES skull, sternum
Sesamoid bone - Answers small, flat, oval-shaped; suspended in tendons
EXAMPLE patella
Irregular - Answers bones that do not fit in the 4 above categories
, EXAMPLE vertebrae
Depressions - Answers -allow vessels and nerves to run along a bone, allow two bones to
articulate
-Facet, fossa, fovea, groove
Openings - Answers -holes in the bone for vessels and nerves
-Meatus (canal), fissure, foramen
Projections - Answers -bony extensions that serve as attachment sites for muscles, tendons,
ligaments, and some joints
-Condyle, crest, head, tubercle/tuberosity, epicondyle, process, spine, protuberance, line
Marrow cells - Answers hematopoietic stem cells produce blood cells, also includes adipocytes
Osteoblasts - Answers build new bone (ossification)
Osteoclasts - Answers break down bone
Osteocytes - Answers mature bone cells
Intramembranous Ossification - Answers Cranial Vault ■ Maxilla/Mandible ■ Clavicles
Endochondral Ossification - Answers Skull base ■ Vertebrae ■ Pelvis ■ Long Bones
For both types of ossification, the first immature bones formed are called.. - Answers primary
bones
ALSO
Consists of irregularly arranged collagen bundles, osteocytes, and some inorganic matrix
Eventually resorbed by osteoclast activity and replaced with.. - Answers mature secondary bone
+
fully formed lamellae, regularly arranged collagen bundles, much more inorganic matrix, and is
therefore a much stronger type of bone
Growth in long bones occurs at - Answers epiphyseal plate
Appositional growth - Answers process by which bones grow in width or thickness
Break down bone to release calcium in times of need or as a result of fracture/normal wear and
tear? - Answers Osteoclasts
