Two major sources of mutation are radiation and reactive oxygen species (ROS).The reactive oxygen species hypothesis for aging postulates that 

1) Senescence results from the accumulation of DNA, lipid, and protein damage inflicted by ROS of mitochondrial origin; and

2) Mitochondria of long-lived species should produce high ROS than do mitochondria of short-lived species.

3) the capacity of mitochondria to consume ROS might distinguish long-lived species from short-lived species, rather than differences in ROS generation. 

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#Question id: 3619

#Unit 8. Inheritance Biology

Alleles that are both expressed in a heterozygote are

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#Question id: 6958

#Unit 5. Developmental Biology

Vg-1 and wnt are used in both frogs and chicks to establish a body axis, although in chicks this is the antero-posterior axis instead of the dorso-ventral axis. What is the region of the chick embryo that is thus analogous to the Nieuwkoop center?

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#Question id: 5692

#Unit 8. Inheritance Biology

Aneuploids can be produced several ways except

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#Question id: 3672

#Unit 3. Fundamental Processes

During initiation of replication

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#Question id: 12580

#Unit 10. Ecological Principles

When levels of CO2 are experimentally increased, C3 plants generally respond with a greater increase in productivity than C4 plants. This is because