70 Chapter 4
Glucose Glycolysis Pyruvate^ Lactic acid^(^) Mitochondrion (^)
(^) ATP NADH (^)
Acetyl-CoA (^)
NADH (^)
(^) Citric H 2 O (^)
(^) Cytoplasm acid (^)
cycle^ NADH^
(^) ys te m (^)
(^) n p (^) so rt s (^)
(^) o n tr a (^)
(^) c t r (^)
(^) Ele
Extracellular ATP^
fluid (^)
(^) Plasma (^)
membrane (^)
O (^2)
(^) CO (^2)
Figure 4- 6 An overview of cellular respiration.
(^) ®
Learning
Cengage ©
Table 4- 1 ATP Production by Cellular Respiration
Step Product Total ATP Produced
Glycolysis^4 ATP^2 ATP (4 ATP produced minus 2 ATP to start cycle)^
2 NADH 2 6 ATP
Acetyl-CoA production 2 NADH 2 6 ATP
Citric acid cycle^2 ATP or 2 GTP^2 ATP or 2 GTP^
(^) 6 NADH 2 18 ATP
2 FADH 2 4 ATP
(^) 38 ATP or 36 ATP and 2 GTP
(^) ®
Learning
Cengage ©
The actual three-dimensional structure of DNA was
discovered in the 1950s by three scientists. It was a British
chemist, Rosalind Franklin, who discovered that the
molecule had a helical structure similar to a wind-ing
staircase. This was accomplished when she con-ducted an
X-ray crystallographic analysis of DNA. Her photograph
was made in 1953 in the laboratory of an-other British
biochemist, Maurice Wilkins. Two other researchers were
also studying the DNA molecule at
this time: James Watson, an American postdoctoral
student,- and an English scientist, Francis Crick, at
Cambridge University in England. After learning in-
formally of Rosalind Franklin’s discovery, they worked
out the three-dimensional structure of the DNA mol-ecule.
Rosalind Franklin’s discovery of the helical nature of
DNA was published in 1953, but Watson and Crick learned
of her results before they were published. James Watson
and Francis Crick won the Nobel Prize in