unit 1 part 2

Question 1

aspect
How birds manage to unerringly travel between distant locations is one aspect that has fascinated observers for centuries.

Answer 1

n., a part or feature

Question 2

breed

Answer 2

v., to reproduce

Question 3

diurnal

Diurnal migrants, those migrating during the day, take their cues from the location of the sun.

Answer 3

adj .. active during the day

Question 4

endure

enduring some of the coldest conditions on Earth.

Answer 4

v·., to live under difficult

conditions

Question 5

evolve

Scientists believe that birds evolved from dinosaurs.

Answer 5

v., to develop gradually

Question 6

fascinate

The study of the lives of birds fascinates many people.

Answer 6

v .. to interest greatly

Question 7

feat

researchers have attempted to understand this feat.

Answer 7

n .. a difficult act or achievement

Question 8

fuel
At the start of its trip, about 55 percent of its body weight is made up of the fat necessary to
fuel this amazing journey.

Answer 8

v., to provide energy

Question 9

hemisphere

only species of seabirds migrate to the Southern Hemisphere to breed.

Answer 9

n., one half of the Earth; also,

one half of a sphere

Question 10

imperative
It is imperative to keep dogs and cats away from the bird breeding area.
It is our imperative to protect the natural environment.

Answer 10

n .• a priority; an urgent need

Question 11

inhabit
Migration is the regular movement of animals between their breeding grounds and the areas that they inhabit during the rest of the year.

Answer 11

v., to live in

Question 12

migration
The most common form of bird migration involves traveling to higher
latitudes to breed during the warm season and then returning to lower latitudes during the nonbreeding period.
Scientists study the habits of migratory birds.

Answer 12

n .. movement from one place

to another

Question 13

navigation
Most studies have found that migratory birds all have some ability to navigate and an innate drive to travel in a particular direction.

Answer 13

n .. finding the way from one

place to another

Question 14

nocturnal

Nocturnal migrants, those species that travel at night, seem to take their navigational cues from the stars.

Answer 14

adj .• active at night

Question 15

observer
bird migration in particular has fascinated
observers for centuries.

Answer 15

n .• a person who watches

something

Question 16

obscure

When the stars are obscured by clouds, nocturnal migrants may become confused and return to land or stray off course

Answer 16

v., to make difficult to see

Question 17

optimal
This form of migration allows birds to breed tn areas that provide optimal conditions for nesting and feeding their young.

Answer 17

adj.. best, most favorable

Question 18

species

Answer 18

n .• type; a basic group in

biological classill.cation

Question 19

stray

Answer 19

v., to leave the correct route;become separated from the

group

Question 20

windswept

Answer 20

adj., unprotected from the wind