Transcription factors are proteins that regulate the transcription of genes. How do enhancers and repressors differ?
A) Repressors and enhancers both decrease the rate of transcription.
B) Enhancers decrease the rate of gene expression and repressors increase the rate of expression.
C) Enhancers increase the rate of transcription and repressors decrease the rate of transcription.
D) Repressors increase the rate of gene expression then decrease the rate. Enhancers decrease the rate of transcription then increase the rate of gene expression.

After reading the paragraph below, answer the questions that follow. researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. the robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract. all of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. this is an example of a. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.

What are some possible short and long term medical concerns for crew members on longer space exploration trips

Ecologist have observed a sharp increase of sulfur dioxide in the air . what might be a possible consequence of excessive sulfur dioxide in the air ? a. acid rain b. ozone layer depletion c.ozone layer hole d.increase in sea levels