All animals, including you and I, are made of the same basic building block called the animal cell. Animal cells are generally smaller than plant cells and lack a cell wall and chloroplasts;
these are organelles pertinent to plant cells.
In the title “Animal Cell Parts and Functions”, the word “Part” pertains to “Organelles”; these are specialized parts inside a living cell.
Organelles in an animal cell are suspended in a fluid called the cytoplasm. A cell membrane encloses the cytoplasm and all contents of the animal cell.
Animal Cell Parts and Functions | Summary Table
| Organelle | Summary of Function |
|
Cell membrane |
|
|
Cytoplasm & Cytoskeleton |
|
|
Nucleus |
|
|
Ribosomes |
|
|
Endoplasmic
Reticulum (ER) |
Summary of the function of the Smooth ER:
Summary of the function of the Rough ER:
|
|
Golgi apparatus |
|
|
Mitochondria |
|
|
Lysosomes & Peroxisomes |
|
|
Vacuoles |
|
|
Cilia &Flagellum |
|
Animal Cell Parts and Functions | Details
The Cell Membrane
Think of the cell membrane like the border control of the cell, controlling what comes in and what goes out.
The cell membrane also called the plasma membrane encloses the animal cell and its contents. It separates the inside of the cell from the outside. It is a selectively permeable membrane that monitors what enters and exits the cell.
The cell membrane is mostly made up of special proteins (membrane proteins) and lipids (phospholipid).
The phospholipids are arranged is a double layer – the Phospholipid Bilayer. The top and bottom of this double layer arrangement are hydrophilic (water-loving) while the inside of the double
layer arrangement is hydrophobic (water-hating).
Most cell membranes have special membrane proteins embedded in the phospholipid bilayer. These proteins help in the transportation of molecules across the cell membrane. The proteins have other
functions such as giving a shape to the cell as well as adhesion to neighboring cells to form tissues.
The Cytoplasm and the Cytoskeleton
The animal cell is filled with a solution of water and nutrients to form a fluid called the Cytoplasm. Organelles of the animal cell are suspended in the cytoplasm. The cytoplasm contains the cytoskeleton; a network of protein filaments that reinforce the cell and hold all structures together.
There are three main types of filaments namely; Microfilaments, Intermediate filaments and Microtubules.
Microfilaments and intermediate filaments are thinner than microtubules. They stretch over the whole cytoplasm helping to maintain cellular shape. Microtubules are straight hollow filaments that act like support beams. They help guide the movement of organelles as well as chromosomes.
The main microtubule organizing center is called the Centrosome. It is located close to the nucleus. Not only does it participate in the network of microtubules, it is involved in the cell
cycle.
The Nucleus
The nucleus is the command center of a cell. This is where most of the cell’s DNA is stored. It is enclosed in a double membrane. The double membrane has pores which allow the movement of molecules between the nucleus (Nucleoplasm) and the cytoplasm.
The Nucleolus is located inside the nucleus. The main function of the nucleolus is to make ribosomal RNA (rRNA). rRNA then combines with special proteins to form the basic units of ribosomes. Once these units are formed the nucleolus releases them out of the nuclear envelope where they will be fully assembled into ribosomes. The nucleus sends messages to the ribosomes through messenger RNA, (mRNA). mRNA carry out orders from the nucleus to the rest of the cell.
Long strands of DNA in the nucleus combine with special protein to form long fibers called Chromatin. Chromatin is then used to make Chromosomes.
The number of chromosomes present in a cell depends on the species of animal. The human sperm and egg cell both have 23 chromosomes. The number of chromosomes found in all of the other body cells
is 46.
Here is a quick guided tour of the animal cell.
Ribosomes
Ribosomes are tiny structures found floating around in the cytoplasm or attached to the ER. Ribosomes maybe small but are essential for the proper functioning of a cell. They are responsible for
protein synthesis.
The Endoplasmic Reticulum (ER)
The ER is like a factory for the production of proteins and lipids. It also forms a network of tubes that carry substances around the cell. There are two types of ER; the rough ER and the smooth ER. They have slightly different structure and function.
The rough ER is called “rough” because it is studded ribosomes while the smooth ER is called “smooth” because it lacks ribosomes.
The Smooth ER contains enzymes that are involved in the creation of lipids. Other enzymes in the smooth ER help in the detoxification of drugs and alcohol.
Ribosomes attached to the Rough ER are responsible for protein synthesis. These ribosomes assemble amino acids into polypeptides. When synthesis is complete the ER packages the polypeptides in special vesicles and sends them to the Golgi apparatus where they will be packaged and “shipped”.
The Golgi Apparatus
The Golgi apparatus is the cell’s shipping department. It processes and packages proteins and sends them out to where they are needed.
The Golgi apparatus is made up of stacks of membranous layers that are referred to as Golgi bodies. Golgi bodies create hormones from proteins. They can also combine proteins with carbohydrate to make other molecules such as snot (nasal mucus).
The golgi apparatus packages its products into sacs called vessicles. These sacs have membranes made of phospholipid just like the cell membrane. These vessicles are then shipped to other parts of the cell or out of the cell.
Mitochondria
The mitochondrion (singular) is the power house of the cell. It is responsible for converting the food that you eat into energy that your body can use. The energy that our body uses is called Adenosine Triphosphate (ATP). ATP is a super energized molecule that gives you the energy you need to function properly.
Mitochondria generate ATP from carbohydrates and fat and other fuels. They also assist in cell growth, cell cycle and cellular death.
A mitochondrion is a smooth oblong organelles with an outer smooth membrane and an inner membrane. The inner membrane has numerous infoldings called Cristae.
Some cells such as muscle cells need to power and hence have a lot more mitochondria than other cells.
Lysosome & Peroxisome
Lysosomes are digestive sacs that contain enzymes to break down cellular waste or debris from outside the cell into new building material.
Lysosomes break down big macro molecules into smaller molecules which can be used to nourish the cell. They also break down damaged organelles and destroy foreign invaders such as bacteria.
Peroxisomes are similar to Lysosomes in structure. They break down molecules by oxidative reaction and produces hydrogen peroxide – harmful compound. Peroxisomes break down the hydrogen peroxide
to produce water. Or they may use the hydrogen peroxide to break down other molecules. Peroxisomes are also involved in the synthesis of lipid and bile acid (liver cells).
Vacuole
Vacuoles are storage sacs filled with fluid. They store food, water and waste products. The vacuoles in animal cells are generally smaller than that in plant cells. Animal cells can have multiple
small vacuoles while plant cells usually have a single large vacuole.
Cilia and Flagellum
Some animal cells have cilia or a flagellum. Cilia (singular is cilium) are hairlike processes that extend from the cell’s surface. Flagellum is a wipe-like tail that protrudes from the cell. Both cilia and flagella are made of small protein fibers known as microtubules. Some cells have neither cilia nor a flagellum. A sperm cell has a flagellum. It uses its flagellum to propel itself through the female reproductive tract. Lung cells have cilia. They use cilia to push mucus up and out of the lungs.
Here is a quick guided tour of the animal and plant cell.
Do you have anything to share about ‘Animal Cell Parts and Functions’? Tell us in the comment section below.
Write a comment
DL (Tuesday, 24 January 2017 22:45)
Very useful.... Congrats from bottom of the heart.keep on!!
MC (Monday, 30 January 2017 21:24)
Good Job!! Very nice page
K.Z.. (Thursday, 09 February 2017 05:07)
Thank you so much for helping me out with my science project. The page is great! :)
Doreen (Sunday, 12 March 2017 22:09)
thanks for letting me know something
Kirui (Sunday, 19 March 2017 10:50)
Thanks alot it has really assist me
DAYNA (Wednesday, 17 May 2017 19:39)
Very interesting
christian (Tuesday, 05 September 2017)
thank you so much
Julie (Wednesday, 13 September 2017 11:45)
Very helpful information
aaric (Wednesday, 27 September 2017 01:51)
so cool
ossas (Friday, 27 October 2017 11:59)
so cool
joe (Friday, 03 November 2017 20:56)
cool
JJ (Sunday, 03 December 2017 22:15)
What about the definition for Nucleolus?
JJ (Sunday, 03 December 2017 22:17)
Besides that... good job!
anita (Tuesday, 23 January 2018 15:25)
bravo
Ryan (Wednesday, 24 January 2018 02:25)
Thanks a lot..
Max (Monday, 05 February 2018 18:57)
Thx, very helpful
puseletso (Tuesday, 06 February 2018 19:42)
thx,it realy is helpfull
asda (Tuesday, 13 February 2018 20:40)
you helped me so much thanks
dayz (Friday, 16 February 2018 20:46)
Thanks a lot really helpful
Nyeche chimankpa uchendu (Saturday, 03 March 2018 21:17)
Oh tank u so much..my exams are starting next week..cellular physiology
shivu (Thursday, 08 March 2018 19:15)
Interesting ☺
Lucy N.Dossen (Friday, 23 March 2018 00:36)
Thanks for giving me reliable source on my assignment,i appreciate it.
dev (Wednesday, 28 March 2018 16:32)
Thanks! very useful website for a homeschool kid
bruh (Thursday, 29 March 2018 06:24)
thanks
ronan (Thursday, 05 April 2018 02:52)
very helpful Thank you
miria eunice (Monday, 16 April 2018 15:56)
am thank full in fact
nigam yadav (Friday, 18 May 2018 09:51)
nice picture of animal cells
David Allen Hood (Tuesday, 26 June 2018 22:07)
No way this came about by chance
Adamu Makoda (Thursday, 05 July 2018 18:28)
very good document...
bebe lab (Sunday, 29 July 2018 11:12)
very impressing
ilyas (Sunday, 29 July 2018 21:12)
thanks a lot and it is very helpful. May almighty God help you.
Haribe Allsack (Sunday, 16 September 2018 17:46)
Thank you!
DSlayer (Monday, 17 September 2018 11:26)
very nc and thanks
DDestroyer (Monday, 17 September 2018 11:45)
very bati no thanks :)
sam (Monday, 17 September 2018 19:39)
rlly insightful for ma homework. thanks
ella (Sunday, 23 September 2018 11:43)
brilliant website
jj (Tuesday, 25 September 2018 00:48)
brilliant
Narifa Hira (Monday, 08 October 2018 13:17)
The soo much because my teacher is a serious man mad when it comes to homework �
But what about nucleolus ???
the real donald trump (Tuesday, 09 October 2018 17:09)
author
Just a Random Kid (Wednesday, 17 October 2018 01:36)
Thank You So Much!!! Got a Science Test Tomorrow about Microbes/Plants/and Cells.
ocean eyes (Sunday, 21 October 2018 07:21)
loved this i feel very intelligent now and not a dumb blonde lol hate stereotypes
DAVID GEORGE (Friday, 23 November 2018 14:13)
THANK YOU!!!!!!!!!! # VERY HELPUL#............
Anonymous (Monday, 26 November 2018 16:24)
Last day preparation....
Abu Hurerah (Tuesday, 04 December 2018 14:56)
Very Good
freddy (Sunday, 27 January 2019 08:12)
thank you very much
Lol (Tuesday, 29 January 2019 07:31)
Good
kherly (Tuesday, 12 February 2019 05:46)
thank you so much:)
*yeboah k.john (Monday, 04 March 2019 10:58)
What a marvellous work done.keep it up
Saviour Suah (Wednesday, 13 March 2019 18:49)
Thanks you are a great help to me
Woop woop (Wednesday, 10 April 2019 01:48)
Thank you so much!!
Name (Sunday, 19 May 2019 13:57)
message
Emmanuel (Sunday, 26 May 2019 23:01)
What a wonderful points keep the ball moving
Kaylee Rider (Sunday, 14 July 2019 01:32)
Thanks for the info!!! Y'all are really awesome!!! I've used this article more than once!!! It is very accurate!!! It is also very useful!!! Good job you guys!!! Enjoy!!!
yusuf isah yusuf (Wednesday, 21 August 2019 23:44)
thank you so much sir.
`12e342 (Wednesday, 23 October 2019 21:59)
graet site
matilda (Friday, 06 December 2019 22:45)
very informative
Big Boy (Friday, 06 December 2019 22:49)
Very good and informative.
Anando (Wednesday, 29 January 2020 01:20)
Thanks, I really needed this for Science class.
Lol (Thursday, 27 February 2020 11:42)
Que
Science (Wednesday, 25 March 2020 10:37)
Thank u a lot now my project on cells is perfect