In the Northern Hemisphere, Seasonal Variation in Temperatures Is Caused

question 57

Multiple Choice

In the Northern Hemisphere, seasonal variation in temperatures is caused mainly by ____.

• A) the Earth's elliptical orbit taking it closer to and farther away from the sun
• B) the Earth's tilt on its axis of 23.5^o
• C) seasonal variation of energy output from the sun
• D) warm equatorial air masses rising and spreading north and south
• E) uneven warming of the ocean's surface water

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Definitions:

Cleavage

A cellular division process in early animal embryo development, where the zygote undergoes multiple cell divisions without growth, leading to a multicellular stage.

Karyotype

The number and appearance of chromosomes in the nucleus of an eukaryotic cell. The term is also used for the complete set of chromosomes in a species or an individual organism.

G₂ Phase

A phase in the cell cycle where a cell has completed DNA synthesis and enters a period of growth and preparation for mitosis.

Prophase

The first stage of cell division in both mitosis and meiosis, where chromosomes condense and the nuclear envelope breaks down.