Basic cell structures review

Key terms

Term	Meaning
Cell	Basic unit of living things
Organelle	Specialized cell structure that performs a specific function

Common cell organelles

Organelle	Function	Found in all cells?
Cell membrane	Supports/protects cell; controls movement of substances into/out of cell; separates cell from its environment	Yes
Cell wall	Stiff, rigid structure that surrounds the cell membrane to support/protect the cell	No
Cytoplasm	Clear, thick, jelly-like substance inside the cell membrane that contains the other organelles	Yes
Ribosome	Small bodies floating in cytoplasm (or attached to the endoplasmic reticulum) that make proteins	Yes

Cell movement structures

Organelle	Function
Flagella	Whip/tail-like structure that helps propel the cell forward
Cilia	Short, hair-like structure that surround the cell and help it move
Pseudopodia	Extension of cytoplasm into the cell membrane that allows the cell to “crawl”

What else should I know about basic cell structures?

All cells contain genetic information. All living things must have genetic information that provides instructions for cellular activities. Some cells keep this genetic information in a nucleus, while others store it differently.
The cell wall and cell membrane are not the same thing. All cells have a cell membrane, but not all cells have a cell wall. Cell walls are very rigid, which makes the cell harder to move. They can be made up of a variety of substances, so cell walls in plant cells are different than those found in bacterial cells.

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varsha.arelli
Posted 6 years ago. Direct link to varsha.arelli's post “is a Flagella found in bo...”
is a Flagella found in both prokaryotic and Eukaryota cell and same goes for cillia
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(22 votes)
Answer
- Rhizul Tripathi
  Posted 5 years ago. Direct link to Rhizul Tripathi's post “Yes, Flagella is found in...”
  Yes, Flagella is found in both prokaryotic cells and Eukaryota cell. For example- Bacteria have flagella:Prokaryotic cells
  
  Euglena have flagella: Eukaryota cells
  
  Only Eukaryota cells have cilia, not Prokaryotic cells
  Comment on Rhizul Tripathi's post “Yes, Flagella is found in...”
  (27 votes)
Jacqueline Watkins
Posted 4 years ago. Direct link to Jacqueline Watkins's post “Which cells have cell wal...”
Which cells have cell walls?
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(8 votes)
Answer
- ?BEST20042007?
  Posted 3 years ago. Direct link to ?BEST20042007?'s post “Plant cells, algae, fungi...”
  Plant cells, algae, fungi and in all of the prokaryotes with the exception of the mollicute bacteria. Hope this helps!
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  (7 votes)
yanyancastle
Posted 4 years ago. Direct link to yanyancastle's post “what are the difference b...”
what are the difference between plants and animal cells
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(6 votes)
Answer
- IsotonicFlaccidCell21
  Posted 4 years ago. Direct link to IsotonicFlaccidCell21's post “plant cells tend to have ...”
  plant cells tend to have all the features of an animal cell: mitochondria, nucleus, cytoplasm, ribosomes and cell membrane. But plants also have a vacuole, a cell wall, and chloroplasts.
  Furthermore, they can grow in different ways. Plant cells (more specifically stem cells) are usually pluripotent stem cells, meaning they can differentiate into any cell. This is why they never cease to grow and can regenerate. Animals only have pluripotent stem cells when they are embryos or early fetuses. But once they are adults, they will mainly have multipotent stem cells which are for repair mainly.
  But plant cells do have an extra feature: they can elongate! This allows them to be very big.
  Comment on IsotonicFlaccidCell21's post “plant cells tend to have ...”
  (9 votes)
ROSI A
Posted a year ago. Direct link to ROSI A's post “Why are atoms non-living ...”
Why are atoms non-living things?
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(5 votes)
Answer
- lishaleo3
  Posted a year ago. Direct link to lishaleo3's post “An atom is not a living t...”
  An atom is not a living thing because it does not share the seven characteristics of living things which are: order, sensitivity or response to the environment, reproduction, growth and development, regulation, homeostasis, and energy processing; In fact, it does not possess any of the characteristics.
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  (8 votes)
Nobu
Posted 5 years ago. Direct link to Nobu's post “Are the structures within...”
Are the structures within cells made of even smaller cell-like components or of atomic structures, ie. carbon atoms, etc ?
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(5 votes)
Answer
- Bob Yuan
  Posted a year ago. Direct link to Bob Yuan's post “At the biological level, ...”
  At the biological level, all organisms we now find can be classified as carbon-based, that is, our basic building blocks are made up of carbon-14 and other compounds.
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  (2 votes)
Nedjerlie Tessier
Posted 10 months ago. Direct link to Nedjerlie Tessier's post “Are cells bigger than ato...”
Are cells bigger than atoms?
Are there atoms on cells?
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(1 vote)
Answer
- ?PURPLE4VICTORY?
  Posted 10 months ago. Direct link to ?PURPLE4VICTORY?'s post “Yes and yes!! Atoms are s...”
  Yes and yes!! Atoms are smaller than cells and they make up cells.
  Comment on ?PURPLE4VICTORY?'s post “Yes and yes!! Atoms are s...”
  (12 votes)
Shawna Jin
Posted 4 months ago. Direct link to Shawna Jin's post “How to learn biology bett...”
How to learn biology better?
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(4 votes)
Answer
- xiaobaitu2011
  Posted 2 months ago. Direct link to xiaobaitu2011's post “Study...that's it.”
  Study...that's it.
  Comment on xiaobaitu2011's post “Study...that's it.”
  (4 votes)
Jonan Byamukama
Posted 4 years ago. Direct link to Jonan Byamukama's post “How do ribosomes make pro...”
How do ribosomes make proteins?
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(4 votes)
Answer
- RowanH
  Posted 4 years ago. Direct link to RowanH's post “There are a few pages and...”
  There are a few pages and videos on this process here on Khan Academy, it is called translation.
  Start here, then see the other things in that playlist for even more info if you want
  /science/biology/gene-expression-central-dogma/translation-polypeptides/v/translation-mrna-to-protein
  Comment on RowanH's post “There are a few pages and...”
  (3 votes)
valente.2279891
Posted 5 years ago. Direct link to valente.2279891's post “are cells and atoms the s...”
are cells and atoms the same size or cells are smaller or bigger then them?
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(2 votes)
Answer
- B.K.
  Posted 5 years ago. Direct link to B.K.'s post “Cells are much larger tha...”
  Cells are much larger than atoms. Atoms are the basic building block of all matter; cells are the basic unit of life.
  Comment on B.K.'s post “Cells are much larger tha...”
  (7 votes)
Matthew Van Groll
Posted a year ago. Direct link to Matthew Van Groll's post “what does the cell wall h...”
what does the cell wall help for?
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(2 votes)
Answer
- 404Ac3N0tF0und
  Posted a year ago. Direct link to 404Ac3N0tF0und's post “It helps with providing a...”
  It helps with providing a rigid and stiff structure to support and protect cells. Isn't apparent in all cells.
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  (6 votes)