Week 1 Review: Cell Theory and Cell Structure

In the year 2138, scientists on a distant space colony are studying the origins of life in advanced bio-domes. Evidence obtained through futuristic scientific investigations has led to an updated understanding of cell theory. Which statement describes a component of the original cell theory that was removed because of new scientific knowledge?

• All living things are made of cells.

• All cells come from other preexisting cells.

• Cells form through spontaneous generation.

• Cells are the basic structural and functional units of life.

Answer explanation

The original cell theory included the idea that cells form through spontaneous generation. However, this was disproven by experiments showing that cells arise from preexisting cells, leading to its removal from the current cell theory.

In a futuristic space colony, scientists are trying to study alien cells to develop advanced medical technology. Which invention from the 17th century enabled the development of modern cell theory, making this research possible?

• X-rays

• computers

• the light microscope

• the scanning electron microscope

Answer explanation

The light microscope, invented in the 17th century, allowed scientists to observe cells for the first time, leading to the formulation of modern cell theory. Other options like X-rays and computers came much later.

In the year 3025, scientists discover a new robotic plant and a robotic animal, both designed to mimic living things. According to the Cell Theory, what can you conclude about these two very different bio-inspired robots?

• Robotic plants have cells, but robotic animals do not.

• They are both made of one or more cells.

• They both come from the same kind of cell.

• They both come from a non-living organism.

Answer explanation

According to Cell Theory, all living things are composed of cells. Therefore, both plants and animals are made of one or more cells, which is the correct conclusion about these organisms.

In the year 2125, scientists aboard the interplanetary research station have revisited the foundational principles of biology using advanced technology. The combined futuristic observations of Schleiden, Schwann, and Virchow have led to the reaffirmation of the cell theory for all known life forms across planets. Which of the following is not part of this universal cell theory?

• All cells contain a nucleus.

• All cells come from other living cells.

• All living organisms are made of one or more cells.

• Cells are the basic unit of structure and function of all living things.

Answer explanation

The statement "All cells contain a nucleus" is incorrect as not all cells, like prokaryotes, have a nucleus. The other statements accurately reflect the principles of cell theory.

In the year 3025, scientists are designing advanced bio-robots using both ancient prokaryotic and modern eukaryotic cell technology. To ensure compatibility, which of the following cellular structures should they include, as it is found in both prokaryotic and eukaryotic cells?

• lysosome

• mitochondrion

• nucleus

• ribosome

Answer explanation

Ribosomes are the only structures found in both prokaryotic and eukaryotic cells. They are essential for protein synthesis, while lysosomes, mitochondria, and nuclei are specific to eukaryotic cells.

In a futuristic city, advanced nanobots are used to maintain the energy balance within artificial cells. These nanobots are programmed to pump H+ ions from a region of low concentration to a region of high concentration across a synthetic cell membrane, using energy from a micro power source. How would you describe this type of transport across the cell membrane?

• active transport

• passive transport

• facilitated diffusion

• co-transport

Answer explanation

This transport is called active transport because H+ ions are moved against their concentration gradient, from low to high concentration, requiring energy input, typically from ATP.

In a futuristic space colony, scientists are engineering new life forms. Which type(s) of cells in these advanced organisms have their genetic material safely stored within a nucleus?

• bacteria

• plants only

• animals only

• both plant and animal cells

Answer explanation

Both plant and animal cells have their genetic material contained within a nucleus, distinguishing them from bacteria, which lack a nucleus.

In a futuristic city where advanced technology coexists with nature, scientists are designing artificial plants to help sustain life on Mars. Which characteristic should these artificial plants have in common with most real plants?

• They are unicellular.

• They are prokaryotic.

• They produce seeds.

• They are autotrophic.

Answer explanation

Most plants are autotrophic, meaning they produce their own food through photosynthesis. This characteristic distinguishes them from unicellular organisms and prokaryotes, and not all plants produce seeds.

In a futuristic bioengineering lab, scientists are designing synthetic cells for space exploration. Which cell structure is correctly paired with its primary function to ensure the success of these synthetic cells?

• ribosome - protein synthesis

• mitochondrion - movement

• vacuole - cell division

• nucleus - storage of nutrients

Answer explanation

The ribosome is correctly paired with protein synthesis, as it is the cellular structure responsible for translating mRNA into proteins. The other options incorrectly associate structures with their functions.

In the year 2125, scientists have developed artificial green plant cells to power eco-friendly cities. The diagram below shows one such advanced cell. In which structure is solar energy harnessed to produce energy-rich compounds that fuel the city?

• A

• B

• C

• D

Answer explanation

Solar energy is used to produce energy-rich compounds in structure D, which represents chloroplasts. Chloroplasts are the sites of photosynthesis in plant cells, converting sunlight into chemical energy.