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-ology Immunity and Vaccines Endocrine System and Nervous System Pulse Endodontic Surgery Vital Signs Circulatory, Artery, Vein - basics Head and Neck Anatomy Health Cells Parts of the Body Health issue related to immune system Molecular Basis of Inheritance Excretion-Dialysis Medical Careers

Other quiz:

Molecular Genetics › View

What is Cas9 and what does it do?

A. a protein enzyme that cuts both strands of DNA at sites specified by an RNA guide

B. a DNA sequence that binds the Cas9 protein

C. an RNA molecule that binds to target DNA via complementary base pairing

D. a viral protein that disrupts bacterial membranes

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Circulatory / Respiratory › View

Which structure initiates a heartbeat?

A. AV node

B. SA node

C. left ventricle

D. left atrium

E. right ventricle

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