Cell

The video tutorial explains that organisms can be single-celled like bacteria or complex like humans with trillions of cells. It highlights the vast differences in cell size and function, noting that most cells are microscopic. An example of an extreme cell size is the unfertilized ostrich egg, which is the largest single cell, weighing about 1 kilogram.

Which of the following organisms is made up of a single cell?

• Humans

• Bacteria

• Ostrich

• Elephant

Approximately how many cells does a human body contain?

• 100 billion

• 1 million

• 1 trillion

• 100 trillion

What is the typical size of most cells?

• 1/100th of a millimeter

• 1 meter

• 1 centimeter

• 1 millimeter

Which of the following is the heaviest single cell?

• Plant cell

• Bacterial cell

• Human egg cell

• Ostrich egg

How much does an unfertilized ostrich egg weigh?

• 100 grams

• 2 kilograms

• 1 kilogram

• 500 grams