DNA polymerases cannot initiate DNA synthesis on duplex or single-stranded DNA without a primer.

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#Id: 930

#Unit 5. Developmental Biology

Stem cells are sometimes referred to as “undifferentiated” due to this maintenance of proliferative properties.

TLS Online TPP Program

#Id: 1723

#Unit 4. Cell Communication and Cell Signaling

CD23a is found on activated B cells, whereas CD23b is induced on various cell types by the cytokine IL-4.

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#Id: 7540

#Unit 6. System Physiology – Plant

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#Id: 4011

#Unit 2. Cellular Organization

A surprising feature is the lack of conservation of sequence in MAR fragments. They are usually 70% A-T rich. cis-acting sites that regulate transcription are common, as are 5’ introns, and a recognition site for topoisomerase II is usually present in the MAR.

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#Id: 2050

#Unit 8. Inheritance Biology

X-Linked Dominant Trait

a. Both males and females are usually affected; often, more females than males are affected.

b. Does not skip generations. Affected sons must have an affected mother; affected daughters must have either an affected mother or an affected father.

c. Affected fathers pass the trait to all their daughters.

d. Affected mothers (if heterozygous) pass the trait to half of their sons and half of their daughters.