Zoology Final c

Question 1

unique characteristic of birds

Answer 1

• feathers
• evolved from reptilian scales
• makes possible their greatest adaptation - flight

Question 2

structure of feathers

Answer 2

• barbs arise from main feather shaft

- each barb has its own shaft from which the barbules arise

Question 3

which feathers are responsible for birds ability to fly?

Answer 3

• remiges
• primaries
• secondaries

Question 4

remiges feathers

Answer 4

feathers on the wings

Question 5

primary feathers

Answer 5

provide forward propulsion to move the bird through the air
- asymmetrical vanes: the leading vane is relatively narrower than the trailing vane, so that the primary twists as it is pulled downward, acting like propeller

Question 6

secondary feathers

Answer 6

provide lift to keep the bird in the air

• wing is curved in cross-section so that air travels relatively faster over the top of the wing
• the faster air travels, the less pressure it exerts on a service
• Bernoulli effect

Question 7

high speed wings

Answer 7

• longer than wide, taper

- no wing slots

Question 8

broad, rounded wings

Answer 8

• good maneuverability

- low speed flight

Question 9

soaring and gliding wings

Answer 9

• much longer than wide

- high speed

Question 10

long, slotted wings

Answer 10

• terrestrial soaring birds

- can carry heavy loads

Question 11

characteristics of tail feathers

Answer 11

• rectrices
• symmetrical
• responsible for braking, maneuverability and also provide lift

Question 12

characteristics of down feathers

Answer 12

• have barbules that do not interlock
• evolved for purpose of insulation; preceded flight feather, since warm-blooded animals need to be insulated to keep heat in

Question 13

what muscle is responsible for downstroke of birds wing and where does it attach

Answer 13

• pectoralis and attaches on the ventral humerus from the keel

Question 14

what muscle is responsible for the upstroke of birds wing and where does it attach

Answer 14

• supracoracoideus and attaches on the dorsal humerus from the keel

Question 15

what adaptations are found in feet of perching birds

Answer 15

mechanism by which toes auto magically tighten around perch when they land on it, enabling them to perch with minimum of muscular effort

Question 16

respiratory system in birds

Answer 16

one way flow of sir through lung increase efficiency

Question 17

one-way flow of air

Answer 17

• air from trachea bypasses lungs and enters the posterior air sacs
• air passes from posterior air sacs through lungs to anterior air sacs
• air passes from anterior air sacs back out of trachea

Question 18

flight adaptations

Answer 18

• air sac system reduces eight of bird which increase power/weight ratio
• reduced weigh tof skeleton without reducing its power by extending air sacs through hollow, pneumatic bones reinforced by struts
• birds have relatively large heart
• sexual organs atrophy during non-breeding season, and only left ovary develops during breeding season
• homiothermic which allows for higher metabolic rate

Question 19

homiothermic

Answer 19

warm-blooded

Question 20

brain of the bird

Answer 20

• cerebral cortex
• hyperstriatum
• cerebellum

Question 21

cerebral cortex

Answer 21

poorly developed, and is not associated with higher behavioral processes as it is in mammal

Question 22

hyperstriatum

Answer 22

higher behavioral processes are centered here

- not found in mammals

Question 23

cerebellum

Answer 23

relatively large in birds, need for extreme muscular coordination
- smarter behavior

Question 24

bird vision

Answer 24

• extremely good visual acuity, due to much greater density of cone cells in fovea of retina
• fovea is region of keenest vision
• some birds have two fovea to focus in two places simultaneously

Question 25

hawks and eagle vision

Answer 25

• have telescopic eyes to magnify objects

- visual acuity of hawk is 8 times that of human, enabling it to see food more than a mile away

Question 26

reproduction in birds

Answer 26

• an extremely efficient digestive system allows nestlings to leave nest as soon as possible
• two types of young: altricial and precocial

Question 27

altricial young

Answer 27

• born blind, naked and helpless

Question 28

precocial young

Answer 28

• born fully-feathered and mobile

Question 29

bird migration

Answer 29

• experimental evidence has shown that the sun, stars and earth’s magnetic field are all involved, depending on the species
• undertake very long migrations

Question 30

neotropical migrants

Answer 30

• 170000 sq km of tropical rainfoest is lost a year
• tropical rainforest is home to neotropical birds
• includes those of songbirds
• forest fragmentation

Question 31

how many birds are killed my cats a year

Answer 31

19 million

Question 32

forest fragmentation

Answer 32

• split forests into sections
• causes increased predation because predators hunt on the borders and when split into different sections that results in more borders

Question 33

cowbird parasitism

Answer 33

• brown-headed cowbird lay eggs in other birds nest, since cowbirds are bigger, they get fed over songbirds which causes the songbirds to die

Question 34

what very important fossil is very strong evidence of relationship between birds and reptiles?

Answer 34

• Archeopteryx

- reptilian skeleton, but with true feathers