Locomotion Flashcards
What is involved in the basic plan of the pectoral girdle of vertebrates
Post- temporal Supracleithrum Cleithrum Clavicle Suprascapula Scapula Coracoid
How many bones of the “basic plan” do Osteichthyes have
All 7 elements- smaller coracoid however
How many bones of the “basic plan” do chrondrichthyes have
3 elements
How many bones of the “basic plan” do early tetrapods have
6 basic elements
In early tetrapods is the clavicle longer or shorter
Longer
How many bones of the “basic plan” do amphibians e.g. Frog have
3 elements
What is the interclavicle
Membrane bone developed between collarbones or in front of the breast bone in many vertebrates
What vertebrates don’t have an interclavicle
Marsupials and placental mammals
What is the cleithrum
First appears as part of the skeleton in primitive bony fish. It is a large bone that extends upwards from the base of the pectoral fin and anchors to the cranium above the gills forming posterior edge of the gill chamber
Do agnatha types of fish have girdles
No
What type of fish are Agnatha
Jawless fish
The scapula and coracoid in bony fish is small or large
Small
The ventral clavicle in bony fish is usually what
Reduced
The cleithrum in bony fish is large or small
Enlarged
What are the 3 elements amphibians have
Ossified, scapula and coracoid
Do amphibians have an interclavicle
No
What is the difference between the glenoid fossa in human compared to amphibians
In amphibians it’s less flexible
Name the elements are involved in reptiles
Coracoid and scapulae
Clavicles and interclavicles (lizard)
What element is not present in snakes
Pectoral girdles
In birds are the clavicles fused
Yes at the midline to form the furcula (wishbone)
Describe the coracoid and scapula in birds
Long and slender
Why do birds have very large sternum’
For muscle attachment of wings for flying
Is the interclavicle and coracoid present or absent in mammals
Absent
When are clavicles sometimes absent in mammals?
Ungulates or rodents
What is primitive elasmobranchs
Stiff, triangular paired fins
Base and fin in same horizontal plane I.e. Flat surfaces dorsal and ventral
What are primitive elasmobranchs used for
Used for stabilisers and insignificant in locomotion
How do sharks swim
Lateral undulations
If fins occur singular what are they called
Caudal, anal, dorsal
If fins are paired what are they called
Pectoral and pelvic fins
Fins do not ____. The are ________ and used as _______.
Flap, horizontal, stabilisers
What does sinuous mean
Having many curves and turns, lateral movement of tail
Describe dermal fin rays
Slender rods
Keratinised in elasmobranchs
Ossified or chondrified in bony fish
What are the 3 different types of fins
Ray fins
Fin fold fins
Lobed fins
What are lobed fins
Fleshy muscular lobe at base, precursor to tetrapods limb
What are ray fins
Very flexible, lost components of basal Skeleton, some have no pelvic fins e.g. Perch
What are fin fold fins
Have a broad base e.g cladoselache (extinct sharks)
What does crossopterygians mean
Have certain features that approach limb features in early tetrapods
What are the functions of fins
Stability, breaking and stearing
Stability of fins
Projecting from streamlined body
Breaking is to do with what kind of fins
Paired fins
What does stealing of fins mean
Control direction of movement
How is forward propulsion in fish achieved
Achieved by lateral flexion of vertebrae caused by axial musculature which causes lateral undulations
What way does the caudal fin move to move forward
Side to side
Movement of tail exerts a _______ and _________ force against the resistance of the _____
Backward, lateral, water
The components of resistance propel fish where
Forward
The lateral component will tend to make body of a fish do what
Move sideways but this is minimised by the fact the body is large and it’s centre of gravity is more difficult to overcome
What are the 3 different axis of movement
Roll, pitch and yaw
What is the roll movement
Side to side
What is pitch movement
Head up and down
What is yaw movement
Twist about a vertical axis
Where did early tetrapods develop limbs from
Lobe finned fish
Do early tetrapods have short or long limbs
Short
The first segment of early tetrapods is almost what
Horizontal
The second segment in early tetrapods is what to the first
Perpendicular to the first
Early tetrapods toes tend to point where
Laterally
What other animals have to s pointing laterally
Urodeles and some primitive reptiles
Functions of limbs
Locomotion
Tools
What are the muscles called that are too weak to support body out of water
Primitive crossopterygians
What happens in water
Propulsion through lateral undulations; Horizontally held fins -> LIFT
Vertically held fins -> THRUST
What happens on land
Same lateral undulations place fins as pivot points; body rotates around pivot; limbs not as strong as tetrapods
What are mudskippers
Walking fish
Terrestrial locomotion
Same method used by early amphibians in order to lift and plant foot -> then tetrapod vertebral column rotates about the pivot point
What types of animals use terrestrial locomotion
Urodeles, lizards, turtles etc
Lifting limb brought what new factor
Axial torque of vertebrae column
What does the humerus articulate with
Glenoid fossa
