Flight

Question 1

Name a species which has secondarily lost its ability to fly.

Answer 1

Kiwi

Question 2

Why does the loss of flight usually occur ?

Answer 2

Inhabit islands with greatly reduced mammalian predation.

Question 3

Why is it energetically costly for a bird to fly ?

Answer 3

Commit huge amounts of the body (pectoral muscle)

Energetically expensive process

Question 4

What do kiwis invest their energy in ?

considering they do not fly

Answer 4

Egg production, Kiwi egg is 30% of body size,

Question 5

Give the key adaptions of the feather fro flight,

Answer 5

Light, Strong, Streamlined, Flexible

Question 6

How have birds achieved lightening of the skeleton ?

Answer 6

Reduced no. of bones 
Hollow bones (no bone marrow)

Question 7

How have birds adapted their skulls for flight ?

Answer 7

Lost heavy jaw structure

Lack muscle and bones

Question 8

Why are birds toothless ?

Answer 8

A gizzard is a lighter solution to molars.

Question 9

Why is it beneficial for birds to oviparous ?

Answer 9

All maternal care takes place outside the body, reducing the weight of the mother.

Question 10

In season, what happens to a female birds one ovary ?

Answer 10

It will enlarge drastically.

Reducing impact of weight outside breeding season.

Question 11

How has a birds skeleton been strengthened ?

Answer 11

Fusion of 2 collar bones to form a wishbone.

Enlargement of the keel

Question 12

The larger the keel….

Answer 12

The more powerful the flight

Question 13

What is the function of the Pectoralis ?

Answer 13

Muscle which enables the downward stroke of the wings,

Question 14

Which muscle is larger, Pectoralis or Supracoracoideus ?

Answer 14

Pectoralis muscle, can be up to 35% of body weight

Question 15

What is the function of the Supracoracoideus ?

Answer 15

Returns wings to upstroke

Question 16

How many other wing muscles do birds have and what is there function ?

Answer 16

48

For Adjustments, landing and take off.

Question 17

What is the primary sense organ of birds ?

Answer 17

Sight

Question 18

Describe the sensory adaptions of birds.

Answer 18

Large eyes
Large brains
Ample processing centres.

Question 19

What structures make up the wing of a bird ?

Answer 19

Forelimb, bones have fused in fingers and hands to make wing.
Powerful tendon
Compact tiny muscles

Question 20

What is the disadvantage of wings ?

Answer 20

Decreased flexibility, In comp. hands and paws.

Question 21

Describe the air foil shape of the wing.

Answer 21

Leading edge is rounded

Tapers to a thin point at the trailing edge.

Question 22

What are the 4 competing forces acting on a bird ?

Answer 22

Weight, Drag

Thrust, Lift

Question 23

Describe what happens on the upper side of the wing to generate lift

Answer 23

Air speed increases over the curved wing relative to the slower lower surface
^ speed means reduced pressure at top of wing, lifting the bird upwards.

Question 24

What does Bernoulli’s principle state ?

Answer 24

That a fast speed of air flow can decrease pressure

Question 25

How is lift generated by birds?

Answer 25

Airfoil sturture of wing
Air flows at different speeds over the curved upper and flat lower wing.
Creates changes in pressure generating lift.

Question 26

Describe what happens on the lower side of the wing to generate lift

Answer 26

Air speed decreased over the lower side of the wing relative to the curved upper surface
This decreased speed, increases the pressure under the wing, pushing wing upwards

Question 27

The more curved the wing…

Answer 27

The greater flight capacity (up to a certain point)

As greater differential between 2 air speeds.

Question 28

If a wing is designed to be excessively curved, what will happen ?

Answer 28

The bird will stall in flight.

Question 29

Describe the breaking mechanism of birds in flight.,

Answer 29

Flare their wings, creating a larger curve in wings, altering air speed and pressure.

Question 30

How do birds counteract drag ?

Answer 30

The generate forward propulsion.

Question 31

List the 2 types of drag.

Answer 31

Friction and induced drag.

Question 32

What is friction drag ?

Answer 32

The consequence of air flow over the body.

Occurs in any object moving through the air.

Question 33

How can friction drag be minimised ?

Answer 33

Minimal number of protrusions.

Smooth outer surface.

Question 34

What is induced drag ?

Answer 34

Consequence of air foil structure. Air travelling at different speeds meet at wing tip and create swirling vortices which hold bird back.

Question 35

How do birds and aeroplanes vary in how they fly ?

Answer 35

A birds wings generates both lift and Thrust

An aeroplanes wings produce lift, and its engine produces thrust.

Question 36

How can migratory birds utilise induced drag ?

Answer 36

Fly in V formation, minimising energy by flying inside wing tip vortices of bird in front.

Question 37

How is thrust generated in wings ?

Answer 37

By flapping wings, The down-stroke creates most of the force whilst the up-stroke acts as a recovery.

Question 38

What is gliding ?

Answer 38

Utilising your own weight to overcome the air resistance of forward motion.
Will gradually lose height.

Question 39

Smaller birds usually use gliding as a flight mechanism.

True or False ?

Answer 39

False, it is usually larger birds,

More able to overcome air resistance using weight.

Question 40

Define soaring,

Answer 40

When a bird maintains or increases altitude without flapping its wings.

Question 41

What is slope soaring ?

Answer 41

Where wind is deflected upwards due to large objects such as cliffs.
Can position themselves in these vortices.

Question 42

What is Dynamic soaring ?

Answer 42

Local updrafts where the wind meets the waves,

Question 43

Give a species which uses dynamic soaring.

Answer 43

Albatross, has huge narrow tapered wings to utilise these