Correct answer is B.

Explanation:
In their nucleus cells contain DNA. The DNA has information about size, shape and function of each cell. When the cell reaches it's full size it stops growing and starts doing whatever it's function is. If more cells are needed then the cell replicates. This explanation excludes answers A and C.

Male and female sexual cells are used to conceive a baby. These cells combine to form a new type of cells. In the first few weeks all types of cells are created. Then the creation of new types of cells stops and existing cells multiply in order to achieve needed number of cells. This explanation excludes answer D.

When we compare an adult person and a baby we can see that, for example, an adult has bigger bones than a baby. This was result of increasing number of existing types of cells without creating any new type.

6 0

3 years ago

Read 2 more answers

23) Why does the earth have seasons? a) the earth is farther from the sun during part of the year b) the earth rotates on its ax

Zigmanuir [339]

Answer:

23. b

25. b

27. b

28. b

29. a

Explanation:

23. The earth have seasons because our Earth orbits around the sun with the Earth's axis of rotation being tilted at an angle of $23.5^{\circ}$ to the plane of the orbit.

24. Ozone in the protect us against the harmful ultraviolet rays coming from the sun.

The ozone layer is found to be located at the Stratosphere's lower part where the variation in its thickness depends on the seasons and the geography.

25. This phenomena is termed as equinox where at this time period, the Sun is Directly over the equator.

26. The part of the earth that provides us the protection against emissions from the sun is 'atmosphere' and it also creates the Aurora Borealis which is formed as a result of the interaction of the charged particles resulting from a storm of proton with the atmosphere giving rise to the aurora.

27. In a closed system, any waste items delivered by one animal types must be utilized by at different species.

28. Positive feedback promotes change as in this the underlying impact is improved or enhanced.

29. Sinks are those locations in a system where resources are collected..

4 0

3 years ago

For many years a mainstay of the economy in Seattle, Washington was commercial fishing. Many people not employed in the fishing

VikaD [51]

Answer:

Basic employment providing non basic employment

Explanation:

Commercial fishing in Seattle provided basic employment by providing fish in large quantity which is usually sold in other areas,also non basic employment services the basic employment

4 0

3 years ago