What is the role of cyclins in a cell? A. to control the movement of microtubules, B. to signal for the cell to divide, C. to stimulate the breakdown of the nuclear membrane, D. to cause the nucleolus to disappear.

Which organelle contains genetic material and controls most cell activities? (1) nucleus (2) cell membrane (3) vacuole (4) endoplasmic reticulum

Earth formed ___________ years ago.

A spacewalking astronaut is stranded a few meters from the space-station door. His jet pack is broken, but he can take it off and toss it in order to propel himself toward the door. In what direction should he toss it?
A. toward the door
B. away from the door
C. toward the Earth
D. The answer cannot be determined from the information provided.

Draw a diagram of a simple galvanic cell.

What are the three stages of the cell cycle ? Explain.

When an electric cell is connected to a circuit, electrons flow away from the negative terminal in the circuit. But within the cell, electrons flow to the negative terminal. Explain.

The table gives the amount of daylight, in hours and minutes, in Sydney, Australia, on the first day of every month. Determine the period of time during a year when Sydney gets a minimum of 12 hours of daylight.

Data as ordered pairs with days of year and decimal hours: (1,14.37),(32,13.73),(60,12.82),(91,11.73)$, (121, 10.75), (152, 10.05), (182, 9.93), (213, 10.45), (244, 11.38), (274, 12.42),$(305,13.45),(335,14.22)

A proposed space station consists of a circular tube that will rotate about its centre (like a tubular bicycle tire), Fig. 5-44. The circle formed by the tube has a diameter of about $1.1 \mathrm{~km}$. What must be the rotation speed (revolutions per day) if an effect equal to gravity at the surface of the Earth $(1.0 \mathrm{~g})$ is to be felt?

In most A&P textbooks, figures are referenced somewhere within the narrative and too often appear on a different page from the related text. How does this description contrast with this textbook?

Express the complex number $\space -\sqrt{3}+i\space$, in the polar form.

Express each of the following numbers in exponential notation with correct significant figures: (a) 704 (b) $0.03344$ (c) $547.9$ (d) 22086 (e) $1000.00$ (f) $0.0000000651$ (g) $0.007157$

The following table displays the energy consumption pattern of Australia. The figures measure the heat content in metric tons (1,000 kilograms) of oil equivalent. Draw a graph that depicts these numbers.

Explain how a fuel-cell breathalyzer works.