Modifications Of Basic Body Plans

Question 1

Alfred Russel Wallace

Answer 1

Helped find the modern science of biogeography
Descent with modification

Question 2

Biological evolution

Answer 2

The process of change by which new species develop from pre-existing species over time

Question 3

What natural barriers prevent organisms from moving freely from one region to another

Answer 3

Impassable topography
Large bodies of water
Unsuitable climate

Question 4

Pentadactyl limb

Answer 4

Had 5 digits
Found in all four classes of terrestrial vertebrates

Question 5

Local diversification by specialisation

Answer 5

The forming of new species and the dispersal of those species in a biogeographical region

Question 6

Biogeography

Answer 6

The study of living organisms all over the world

Question 7

Evolution

Answer 7

The change in genetic composition of a population

Question 8

Mammalian forelimbs in primates- Monkeys

Answer 8

Opposable thumb to increase manual dexterity
Elongated phalanges to grasp and swing

Question 9

Primates

Answer 9

Highest order of mammals with characteristics such as hands for grasping, binocular vision and enlarged brains

Question 10

Ungulates- hoofed animals- horses

Answer 10

Quadrupedal locomotion to maximise stamina
Short humerus and muscle groups being located close to the body to increase acceleration
Elongated lower leg segments to increase stride

Question 11

Mole

Answer 11

Short forelimb
Spade like paw
Nail like claws
Robust metacarpals and phalanges to give strength to paw

Question 12

Whale

Answer 12

Pectoral flipper for keeping equilibrium whilst swimming
Short humerus, radius & ulna
Long metacarpals and phalanges for broad paddling

Question 13

Bat

Answer 13

Short humerus
Long slender radius
Reduced ulna
Elongated metacarpal and phalanges to stretch wing frame for flight
Hook like fists

Question 14

Vestigial structures

Answer 14

Structures removed/ completely lost due to the function they once performed no longer being relevant

Question 15

Examples of vestigial structures

Answer 15

Pelvic girdle of a whale
Reduced coccyx
Human appendix

Question 16

Difference between monkeys in Africa and in Southern America

Answer 16

Africa- narrowed noses
SA- broad noses & prehensile tails

Question 17

Pangaea

Answer 17

Single land mass made of all the continents of the earth

Question 18

Laurasia

Answer 18

Northern Landmass

Question 19

Gondwanaland

Answer 19

Southern Landmass

Question 20

Terrestrial biogeographical regions

Answer 20

Palearctic (Eurasia)
Neotropic (SA)
Afrotropic
Australasian
Indomalayan
Oceanic
Antarctic

Question 21

What are marsupials

Answer 21

Begin life in the uterus but leave to enter marsupium while still an embryo

Question 22

What are Placental mammals

Answer 22

Animals with a placenta connecting the foetus within the uterus to the mother’s circulatory system

Question 23

Dispersal

Answer 23

The movement of population away from their point of origin

Question 24

Biogeographical distribution of species

Answer 24

Single centre of origin
Passive/ active dispersal
Extinction of ancestors
Isolation from ancestors by barriers
Colonisation and adaptation of new areas by separate populations
New species are formed

Question 25

What are Ratites

Answer 25

Large flightless birds

Question 26

Different types of ratites

Answer 26

Extinct- Moa
Extant- Ostrich, Emo & Rhea

Question 27

Physical characteristics of ratites

Answer 27

Flag sternum
Small wings
Heavy leg bones
Large bodies
Strong & thick feet