Cells Science Test - Cheat Sheet:
What’’s a cell?
A cell is typically defined as the smallest and basic unit of life, responsible for all of life’s processes. A
cell can replicate itself independently. Hence, they are known as the building blocks of life .
What kinds of cells are there?
Essentially, there are main cell types, prokaryotic cells and eukaryotic cells. Each has similarities and
differences.
Prokaryotic Cells:
● The structure of prokaryotic cells is less complex than that of eukaryotic cells.
● They are devoid of membrane-bound organelles and an actual nucleus.
● The genetic material, usually a single circular chromosome, is situated outside of a
membrane-bound nucleus in the nucleoid area.
● Prokaryotic cells are smaller in size and are present in bacteria and archaea, among other
species.
● Examples include bacteria like Escherichia coli (E. coli) and Archaea like Methanogens.
Eukaryotic Cells:
● Eukaryotic cells are more complex and larger compared to prokaryotic cells.
● They have a real nucleus that contains the DNA of the cell, which is encased in a membrane-
bound nuclear envelope.
● Organelles that are membrane-bound and found in eukaryotic cells include lysosomes,
mitochondria, endoplasmic reticulum, the Golgi apparatus, and more.
● Animals, plants, fungi, and protists are examples of eukaryotic organisms.
● Plant, animal, fungus, and different protist cells are a few types of eukaryotic cells.
What sizes are cells?
, Cells vary widely in size, but most fall within the range of 1 to 100 micrometers (µm) in diameter.
Here's a breakdown:
Microscopic Cells: Many cells are microscopic and cannot be seen without the aid of a microscope. They
typically range from 1 to 100 µm in diameter. Examples include most animal cells, plant cells, fungal
cells, and many protist cells.
Submicroscopic Cells: Some cells are even smaller and require more powerful microscopes or
specialized techniques to observe. These cells can be as small as a few hundred nanometers (0.1 µm) in
diameter. Examples include certain bacteria, viruses, and organelles within eukaryotic cells.
Macroscopic Cells: A few examples of cells are large enough to be visible to the naked eye without
magnification. These are relatively rare and often form part of multicellular structures. Examples
include the ovum (egg cell) in some animals and certain large plant cells.
What do cells look like?
Depending on their type and function, cells can have a wide range of sizes and shapes. Nonetheless,
many cells have certain shared structures and characteristics.
Cells look like tiny, spherical objects under a microscope, with a distinct boundary known as the cell
membrane or plasma membrane. The contents of the cell are contained by this membrane, which
keeps it isolated from the outside world.
Numerous organelles and structures exist inside the cell that contribute to its functions.
Major Cell Organelles:
Nucleus: Think of it as the cell's "brain" because it controls everything. It's like a command center that
holds all the important instructions (DNA) for the cell's activities.
Mitochondria: Picture them as tiny "powerhouses" because they produce energy (ATP) for the cell.
They're like little batteries that keep the cell running.
Endoplasmic Reticulum (ER):
What’’s a cell?
A cell is typically defined as the smallest and basic unit of life, responsible for all of life’s processes. A
cell can replicate itself independently. Hence, they are known as the building blocks of life .
What kinds of cells are there?
Essentially, there are main cell types, prokaryotic cells and eukaryotic cells. Each has similarities and
differences.
Prokaryotic Cells:
● The structure of prokaryotic cells is less complex than that of eukaryotic cells.
● They are devoid of membrane-bound organelles and an actual nucleus.
● The genetic material, usually a single circular chromosome, is situated outside of a
membrane-bound nucleus in the nucleoid area.
● Prokaryotic cells are smaller in size and are present in bacteria and archaea, among other
species.
● Examples include bacteria like Escherichia coli (E. coli) and Archaea like Methanogens.
Eukaryotic Cells:
● Eukaryotic cells are more complex and larger compared to prokaryotic cells.
● They have a real nucleus that contains the DNA of the cell, which is encased in a membrane-
bound nuclear envelope.
● Organelles that are membrane-bound and found in eukaryotic cells include lysosomes,
mitochondria, endoplasmic reticulum, the Golgi apparatus, and more.
● Animals, plants, fungi, and protists are examples of eukaryotic organisms.
● Plant, animal, fungus, and different protist cells are a few types of eukaryotic cells.
What sizes are cells?
, Cells vary widely in size, but most fall within the range of 1 to 100 micrometers (µm) in diameter.
Here's a breakdown:
Microscopic Cells: Many cells are microscopic and cannot be seen without the aid of a microscope. They
typically range from 1 to 100 µm in diameter. Examples include most animal cells, plant cells, fungal
cells, and many protist cells.
Submicroscopic Cells: Some cells are even smaller and require more powerful microscopes or
specialized techniques to observe. These cells can be as small as a few hundred nanometers (0.1 µm) in
diameter. Examples include certain bacteria, viruses, and organelles within eukaryotic cells.
Macroscopic Cells: A few examples of cells are large enough to be visible to the naked eye without
magnification. These are relatively rare and often form part of multicellular structures. Examples
include the ovum (egg cell) in some animals and certain large plant cells.
What do cells look like?
Depending on their type and function, cells can have a wide range of sizes and shapes. Nonetheless,
many cells have certain shared structures and characteristics.
Cells look like tiny, spherical objects under a microscope, with a distinct boundary known as the cell
membrane or plasma membrane. The contents of the cell are contained by this membrane, which
keeps it isolated from the outside world.
Numerous organelles and structures exist inside the cell that contribute to its functions.
Major Cell Organelles:
Nucleus: Think of it as the cell's "brain" because it controls everything. It's like a command center that
holds all the important instructions (DNA) for the cell's activities.
Mitochondria: Picture them as tiny "powerhouses" because they produce energy (ATP) for the cell.
They're like little batteries that keep the cell running.
Endoplasmic Reticulum (ER):
