Lab 12: Comparative Skeletology Flashcards
Hydrostatic Skeleton
muscles place pressure on fluid in an internal body compartment that resists compression and therefore provides a structure for muscles to act on; the pressure on the fluid also causes changes in the shape of an animal
Spicules belong to…
Sponges
Ossicles and spines belong to …
echinoderms
A chitinous exoskeleton belongs to…
Arthropods
Calcium Carbonate Shells belong to…
Molluscs
Functions of the skeletal system:
-Support for muscles, organs, and soft tissues
-Leverage and movement
-Protection
-Storage of minerals
-Blood cell formation occurs within some bone tissue
Is a bone dry and brittle?
No, a living bone is a vascular tissue - not dry and brittle
What is a cursorial animal?
An animal with limbs adapted for running
Will increasing the length of the leg, increase or decrease stride length?
Increase
Will increasing stride length increase or decrease the speed at which an animal can run?
Increase
What foot position belongs to a cursor?
Unguligrade
Animals with a high degree of extension and flexion in the spine are cursors.
True
What two major regions are the skeletal system of vertebrates composed of?
axial and appendicular
What is the axial skeleton composed of?
the skull, the ribs, the vertebral column, bones of the inner ear, and hyoid
What are the five regions the vertebral column is organized into?
Cervical, thoracic, lumbar, sacrum, and coccyx
What is the function of the cervical vertebrae? How many do human have?
To be a flexible framework for the neck and supports the head; human have 7
What is the function of the thoracic vertebrae? How many do humans have?
The thoracic vertebrae have ribs attached; there are 12 in humans
What is the function of the lumbar vertebrae? How many do humans have?
They help support the body’s weight and are attached to many of the back muscles; humans have 5
In a typical vertebrae, describe the spinous process?
projects to the back and serves as attachment of muscles and ligaments
What are the two projections to each side of a vertebra called?
Transverse processes
What is the hole in the center (between the transverse processes) called?
Vertebral foremen
Name the bones of the upper limb (forelimb):
humerus, radius, ulna, carpals (wrist bones), metacarpals (hand bones), and phalanges (digits or fingers)
Name the bones of the lower limb (hindlimb):
femur, tibia (bigger), fibula (smaller), tarsals (ankle bones), metatarsals (foot bones), and phalanges (toes)
What connects the upper limb to the axial skeleton?
The pectoral
What two bones form the shoulder?
The clavicle and scapula
What is the pelvic girdle formed by?
The hip/coxal bone
The hip bone is formed by the fusion of three bones — what are they?
the ilium, the ischium, and the pubis
The hip socket, which articulates with the femur, is _________(larger/smaller) and ________(shallower/deeper) than that of the shoulder
larger; deeper
A _______ is a fibrous muscle tissue, which attaches muscle to bone. A _______ serves to move the bone or structure the muscle to which it is attached contracts
tendon
A ______ is a fibrous connective tissue, which attaches bone to bone, and usually serves to hold structures together and keep them stable
ligament
The ____________ extends from the base of the skull, in humans, to the spinous process of the last cervical vertebra. This ______ limits flexion (when you move your chin to your chest) of the cervical vertebrae in humans
Nuchal ligament; ligament
_______ indicate where a muscle tendon or ligament attaches
Projections
Which type of projections have a roughened surface?
Projections
The ________ is a ridge that extends laterally across the back of the skull and serves as a point of attachment for strong neck muscles? These muscles serve to position, move, and stabilize the head and cervical vertebrae
Nuchal crest
T/F: the human sternum flat
True
What is a keel?
a bone extension of the breastbone, or sternum, that provides an anchor for flight muscles
Are the bones in sugar gliders and flying squirrels an analogous or a homologous trait?
homologous
The two gliders had an ancestor with the same pattern of bones in its limbs as these animals. What was that ancestor?
Lobe-finned fish
Is the gliding membrane of the two gliders, an analogous trait or a homologous trait?
Analogous
The bones of forelimb/upper limb of vertebrates are _______ structures
homologous
An animal with _______ posture has the full length of its foot, including ankles and foot bones, on the ground during each stride— what foot posture fits this description?
Plantigrade; humans, bears, and wombats are examples
An animal with _______ posture has most of the length of their digits, but not the soles of their feet, in contact with the ground— what foot posture fits this description?
Digitigrade; dogs and cats are examples
An animal with ________ posture walks on their tiptoes, often on hooves, only the hoof touches the ground when standing or moving— what foot posture fits this description?
Unguligrade; deer and horses are examples
