Class: Name: Date: 29 Evolution Ibio662.dyndns.info/DSE/WS/ws_ch29_e.pdf(Second Edition) - 41 - Answers Ch 29 Evolution I 29.1 1 organic 2 inorganic 29.2 1 evolution 2 common ancestor

Class: Name: ( ) Date:

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 36 -

29 Evolution I

29.1 The origin of life (Book 4, p. 29-3)

� Scientists generally believe that the first organisms were formed by joining (1) _____________

molecules together. The organic molecules were produced from simple (2) _______________

substances present in the atmosphere of the early earth.

29.2 Evolution (Book 4, p. 29-5)

� At the present time, scientists generally accept the theory of (1) _______________ (進化), which

suggests that life on earth started from a (2) _______________ _______________ (共同祖先).

A Evidence for evolution: fossils (Book 4, p. 29-5)

1 Types of fossils

� (3) _______________ (化石) are the preserved remains or traces of ancient organisms. They

can be divided into two types:

- (4) _______________ _______________ (體化石): They include body parts of organisms

They provide us with information on the (5) _______________ of ancient organisms and

what they looked like.

- (6) _______________ _______________ (遺跡化石): They include structures caused by

the activity of organisms. They provide us with information on the (7) _______________

of ancient organisms.

� Classify the following fossils into body fossils and trace fossils:

a

b

c

dinosaur dung fossil dinosaur footprint shark tooth fossil

d

e

f

fossilized burrows snail shell fossil dinosaur skull fossil

Body fossils:

(8) _____, _____, _____

Trace fossils:

(9) _____, _____, _____

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 37 -

2 Formation of fossils

� One of the ways of fossil formation and how the fossils are exposed:

1 A fish dies. The soft parts of it decay, leaving the

hard parts like the skeleton. The skeleton is then

buried in mud and sand.

2 After millions of years, the mud and sand become

rock due to great pressure from the upper layers

of sediment (沉積物). Meanwhile,

(10) _______________ begin to deposit in the

fish skeleton and turn it into a fossil.

3 (11) _______________ movement raises the

rock above water.

4 Further earth movement or

(12) _____________ exposes the fossil.

� Other ways to preserve remains of organisms:

- Small animals might get trapped in (13) _______________ (樹脂) secreted by trees. After a

long time, resin turns into (14) _______________ (琥珀), preserving the animals inside.

- Organisms can also be preserved in ice.

3 How a fossil record provides evidence for evolution

� The (15) _______________ of fossils in sedimentary rocks (沉積岩) forms the

(16) _______________ _______________ (化石紀錄).

- In sedimentary rocks, the (17) _______________ (uppermost / lowest) layer is the oldest

rock containing the (18) ____________________ (earliest / most recent) fossils.

� The fossil record agrees with the theory of evolution that:

- existing life forms arose from (19) _______________-_______________ life forms

- organisms became more (20) _____________ in structure and more (21) ______________.

fish skeleton

mud and sand from river

bottom of a lake

fish skeleton becomes a fossil

rock

more recent mud and sand

younger rock layer

older rock layer

fossil exposed

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 38 -

� Scientists can now estimate the age of fossils by (22) _______________ _______________

(放射性同位素定年法). This helps scientists obtain information about the time of existence of

organisms.

� Evolution of the horse: clues from the fossil record

Time 60 million years ago 30 million years ago Today

Bones of

forelimb

Body size

- Body size of horses (23) _______________ over the past 60 million years.

- The horse’s legs became (24) _______________ over time. The number of toes was

(25) _______________.

� Limitations of using fossil records as evidence for evolution:

- There are (26) _______________ _______________ (缺少的環節) in fossil records.

- (27) _______________-bodied organisms usually do not form fossils.

- The bodies of dead organisms may be eaten by other organisms or (28) _______________

before fossilization occurs.

- The conditions in which the organisms died are not suitable for fossil formation.

- Most fossils are (29) _______________ and may be damaged.

- Some fossils are located in (30) _______________ areas.

B Other evidence for evolution (Book 4, p. 29-12)

1 Homologous structures

� Some structures of different species may look very different and perform different functions,

but their designs are basically the same. These structures are said to be (31) _______________

(同源的).

0.4 m 1 m 1.6 m

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 39 -

� Example: The forelimbs of mammals (e.g. humans, horses, bats and whales) perform different

functions, but all of them are (32) _______________ _______________ (五趾型肢). This

suggests that these mammals evolved from a (33) _______________ _______________. Their

limbs (34) _______________ to perform different functions in different environments.

� Identify to which mammal the following limbs belong. State the functions of the limbs.

a

b

c

d

Mammal Bat Horse Human Whale

Limb (a–d) (35) (36) (37) (38)

Function (39) (40) (41) (42)

2 Comparative biochemistry

� By comparing the similarity of certain chemicals (e.g. proteins and nucleic acids) in different

species, the (43) _______________ relationship between them may be deduced.

i) Comparing the amino acid sequence in proteins

� Scientists hold the view that the fewer the differences in the (44) _______________

_______________ sequence in the same type of protein of different species, the fewer the

(45) _______________ which have occurred and the closer the phylogenetic relationship

between the species.

humerus

ulna and radius

carpals

metacarpals and phalanges

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 40 -

� Example: The difference in the amino acid sequence of one of the polypeptide chains of

haemoglobin between humans and five other vertebrates:

Vertebrate Gorilla Rhesus

monkey Dog Chicken Frog

Number of differences in

amino acid sequence in

haemoglobin between

humans and other vertebrates

1 8 15 45 67

- Humans are (46) _______________ (more / less) closely related to gorillas than rhesus

monkeys.

- The evolutionary tree (進化樹) below shows the phylogenetic relationship between humans

and the above five vertebrates. Identify vertebrates I to VI.

I: human

II: (47) _______________

III: (48) _______________

IV: (49) _______________

V: (50) _______________

VI: (51) _______________

ii) Comparing the base sequence of DNA

� The more similar the (52) _______________ sequence of DNA, the closer the phylogenetic

relationship of the species.

� The similarity in the base sequence of DNA between humans and six other species of animals:

Species Gorilla Rhesus

monkey Chicken Mouse Rabbit Squirrel

Similarity in base sequence

of DNA between humans

and other species

97.7% 91.1% 88% 85% 80% 75%

- Humans have a (53) _______________ phylogenetic relationship with gorillas than rhesus

monkeys.

- This (54) _______________ (agrees / disagrees) with the findings when amino acid

sequences in haemoglobin are compared.

I II III IV V VI

ancestor

New Senior Secondary Mastering Biology Oxford University Press 2015 (Second Edition)

- 41 -

Answers

Ch 29 Evolution I

29.1 1 organic 2 inorganic

29.2 1 evolution 2 common ancestor 3 Fossils 4 Body fossils 5 existence

6 Trace fossils 7 activities 8 c, e, f 9 a, b, d 10 minerals

11 Earth 12 weathering 13 resin 14 amber 15 sequence

16 fossil record 17 lowest 18 earliest 19 pre-existing 20 complex

21 diversified 22 radioisotope dating 23 increased 24 longer 25 reduced

26 missing links 27 Soft 28 decay 29 incomplete 30 inaccessible

31 homologous 32 pentadactyl limbs 33 common ancestor 34 modified 35 c

36 b 37 a 38 d 39 flying 40 running

41 handling 42 swimming 43 phylogenetic 44 amino acid 45 mutations

46 more 47 gorilla 48 rhesus monkey 49 dog 50 chicken

51 frog 52 base 53 closer 54 agrees