[求助]GWD9-35

kelly_wong

Scientists studying the physiology

of dinosaurs have long debated whether

dinosaurs were warm- or cold-blooded.

Line Those who suspect they were warm-

(5) blooded point out that dinosaur bone

is generally fibro-lamellar in nature;

because fibro-lamellar bone is formed

quickly, the bone fibrils, or filaments, are

laid down haphazardly. Consistent with

(10) their rapid growth rate, warm-blooded

animals, such as birds and mammals,

tend to produce fibro-lamellar bone,

whereas reptiles, which are slowgrowing

and cold-blooded, generally

(15) produce bone in which fibrils are laid

down parallel to each other. Moreover,

like the bone of birds and mammals,

dinosaur bone tends to be highly

vascularized, or filled with blood

(20) vessels. These characteristics,

first recognized in the 1930’s,

were documented in the 1960’s by

de Ricqlès, who found highly vascularized,

fibro-lamellar bone in several

(25) groups of dinosaurs. In the 1970’s,

Bakker cited these characteristics as

evidence for the warm-bloodedness of

dinosaurs. Although de Ricqlès urged

caution, arguing for an intermediate type

(30) of dinosaur physiology, a generation of

paleontologists has come to believe

that dinosaur bone is mammalianlike.

In the 1980’s, however, Bakker’s

contention began to be questioned, as a

(35) number of scientists found growth rings

in the bones of various dinosaurs that

are much like those in modern reptiles.

Bone growth in reptiles is periodic in

nature, producing a series of concentric

(40) rings in the bone, not unlike the growth

rings of a tree. Recently, Chinsamy

investigated the bones of two dinosaurs

from the early Jurassic period

(208-187 million years ago), and found

(45) that these bones also had growth rings;

however, they were also partially fibrolamellar

in nature. Chinsamy’s work

raises a question central to the debate

over dinosaur physiology: did dino-

(50) saurs form fibro-lamellar bone because

of an innately high metabolic rate associated

with warm-bloodedness or

because of periods of unusually fast

growth that occurred under favorable

(55) environmental conditions? (Although

modern reptiles generally do not form

fibro-lamellar bone, juvenile crocodiles

raised under optimal environmental

conditions do.) This question remains

(60) unanswered; indeed, taking all the evidence

into account, one cannot make

a definitive statement about dinosaur

physiology on the basis of dinosaur

bone. It may be that dinosaurs had an

(65) intermediate pattern of bone structure

because their physiology was neither

typically reptilian, mammalian, nor avian.

Q35:

According to the passage, the discovery of growth rings in the bones of certain dinosaurs served to undermine which of the following claims?

A. That modern reptiles are related to dinosaurs

B. That bone growth in dinosaurs was periodic in nature

C. That dinosaurs were warm-blooded

D. That dinosaurs had an intermediate type of physiology

E. That fibro-lamellar bone is the product of a rapid growth rate

Why not E?

As far as I am concerned, D is more specific than C.

Confused

cathy_gao

Chinsamy’s work raises a question central to the debate over dinosaur physiology: did dinosaurs form fibro-lamellar bone

是否恐龙form fibro-lamellar bone,争论不在于E中所提到的，That fibro-lamellar bone is the product of a rapid growth rate（此话在第一段中已经证明是正确的）

文章主要围绕warm-blooded,所以就算是细节题作答的时候也要围绕中心词，呵呵，个人意见。