Cell Concept Map By Sundus Kahwaji
What are cells?
The smallest structural and functional unit of an organism. Cells are a necessity and are basics of living.
Types
Prokaryote
Eukaryote
What is a eukaryotic cell?
What is a prokaryotic cell?
Prokaryotic cells are unicellular cells.They lack membrane bound organelles. They are the first cells on earth.
Eukaryotic cells are cells with membrane-bound organelles. They can be unicellular or multicellular organisms.
Types of eukaryotic cells
Plant Cells
Animal Cells
Dinosour
Ciliate
Diatom
Dinoflagellate
Apicomplexa
Orchids
Types of prokaryotic cells
Archaea
Bacteria
Organelles
Cell Membrane
Cell Wall
Golgi
Nucleus
Nucleolus
Cytosol
Lysosome
Peroxisome
Mitochondrion
Vacuole
Chloroplast
Endoplasmic Reticulum
Organelles
Nucleus
Ribosome
Vesicle
Endoplasmic Reticulum
Rough ER
Mitochondria
Rough ER
Smooth Er
Peroxisomes
Golgi
Lysosomes
Secretory vesicles
Ribosomes
Microfilaments
Microtubules
Intermediate Filaments
Centrosomes
Organelles
The plasma membrane
Cytoplasm
Genetic material (DNA and RNA)
Flagellum
Ribosomes
Who discovered cells?
The cell was first discovered by Robert Hooke in 1665.
Cell Theory
Structure in all organisms has a basic unit which is cells. Cells are a basic unit of reproduction.
Principles of Cell Theory
All living things are made of cells
All cells arise from preexisting cells.
The main function of a centrosome is to provide and maintain the structure of the cell. It also organizes the microtubles and works to pull the chromatids apart during cell division.
The intermediate filaments provide mechanical support to the plasma membrane from where it comes into contact with other cells.
Microtubules are conveyer belts inside the cells. They move organelles like mitochondria, and chromosomes.
Provides support to the cell.
The mitochondria works to produce the cell's energy. It is considered to be the powerhouse of the cell.
The nucleus is considered to be the brain of the cell. It controls everything inside of the cell.
Nucleolus
The nucleolus makes ribosomes subunits of proteins and ribosomes RNA
What is an animal cell?
They are eukaryotic cells that have membrane-bound organelles that have different function.
They are responsible for the assembly of many proteins.
Smooh ER
They make cellular products like hormones and lipids.
Peroxisomes are responsible for protecting the cells from its own production of toxic hydrogen peroxide.
Principles of Cells
A surrounding membrane
Protoplasm- cell contents in thick fluid
Organelles- structures for cell function
To process and bundle macromolecules like proteins and lipids as they are synthesized within the cell.
Lysosomes help with the process of digestion and the process of waste removal. They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria.
Control center with DNA
Cell secretions are packaged in secretory vesicles. The secretory vesicles are then transported to the cell surface for release.
Ribosomes are a cell structure that produce protein. Protein is needed for many cell functions.
Nucleolus
The nucleolus makes ribosomes subunits of proteins and ribosomes RNA
The nucleolus makes ribosomes subunits of proteins and ribosomes RNA.
They make cellular products like hormones and lipids.
They are responsible for the assembly of many proteins.
Ribosomes are a cell structure that produce protein. Protein is needed for many cell functions.
The mitochondria works to produce the cell's energy. It is considered to be the powerhouse of the cell.
Lysosomes help with the process of digestion and the process of waste removal. They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria.
Peroxisomes are responsible for protecting the cells from its own production of toxic hydrogen peroxide.
The nucleus is considered to be the brain of the cell. It controls everything inside of the cell.
To process and bundle macromolecules like proteins and lipids as they are synthesized within the cell.
Chloroplasts work to convert light energy of the Sun into sugars that can be used by cells. These sugars are used as energy.
Vacuoles are usually found in plant cells. Sometimes in animal cells. These structures are basically compartments that are filled with both inorganic and organic molecules, along with water to support the organelle.
The cell membrane is in charge of protecting the cell from its surroundings. The membrane monitors and controls what comes in and out of the cell.
A cell wall is a layer surrounding plant cells. It can be tough, flexible, and sometimes rigid. The cell wall provides a plant cell structure and protection. In bacteria, the cell wall is composed of peptidoglycan.
Protozoa
This is often confused with cytoplasm, which is the space between the nucleus and the plasma membrane. The primary component of cytosol is water. Water makes up 70% of a cell and is primarily in the cytosol to dissolve other components.
Vesicles are used to transport materials from one place to another. Vesicles also function in metabolism and enzyme storage as well.
Molecule Transport
Passive Transport
Endocytosis
Active Transport
Exocytosis
No energy required
Move due to gradient
Move to equalize gradient
Differences in concentration, pressure, charge
High moves toward low
Molecular movement
Types of Passive Transport
Diffusion
Osmosis
Facilitated Diffusion
Molecules move to equalize concentration.
Special form of diffusion
Fluid flows from lower solute concentration.
Solution Differences
Hypotonic
Hypertonic
Isotonic
Solutes in cell more than outside
Outside solvent will flow into cell.
Solutes greater outside of the cell
Fluid will flow out of cell
Solutes equal in and out of cell
Often involves movement of water.
Differentially premeable membrane
Channels help molecule or ions enter or leave the cell
Channels usually transport proteins.
No energy is used
Process of facilitated transport
Protein binds with the molecule. Then the shape of the protein changes. Finally, the molecule moves across the membrane.
Requires energy
Example is sodium-potassium pump
Movment of large materials
Particles
Organisms
Large Molecules
Movemet is into cells
Types of endocytosis
Bulk-phase (nonspecific)
Receptor-mediated (specfic)
Process
Plasma membrane surrounds material. Then, the edges of membrane meet. Fianlly, membranes fuse to form vesicles.
Forms of endocytosis
Phagocytosis- cell eating
Pinocytosis - cell drinking
Reverse endocytosis
Cell discharges material
Process
Vesicle moves to cell surface. Then, the membrane of the vesicles fuse and the materials are expelled
Differences between animal and plant cells
Animal Cells:
Plant Cells:
Cell wall is absent.
Cytoplasm is denser and occupies more space.
Vacuoles are absent, if they are present then they are samll and temporary.
Cellulose in any form is absent.
Plastids are absent.
Centrosome is present with one or two centrioles.
Prominent and highly complex Golgi bodies are present near the nucleus.
Reserved food stored in the form of glycogen.
Cell walls and cellulose is present.
Cytoplasm only forms a thin line near along the cell wall.
Vacuoles are larger.
Plastids are generally present.
Centrosomes are absent.
Several subunits of the Golgi Apparatus.
Reserved food stored in the form of starch.
Smilar organelles in plant and animal cells
They both contain membrane-bound organelles such as the nucleus, mitochondria, endoplasmic reticulum, golgi apparatus, lysosomes, and peroxisomes.
Chloroplasts are present.
Chloroplasts
In an animal cell, the mitochondria produces the enrgy that the cell uses. On the other hand, plant cells have organelles called chloroplasts that use sunlight as their energy source; the sunlight must be converted into energy inside the cell in a process called photosynthesis
The main function of the centriole is to help with cell division in animal cells. The centrioles help in the formation of the spindle fibers that separate the chromosomes during cell division
What is a plant cell?
Plant cells are eukaryotic cells that are unique in terms of some key aspects.
Cell Walls
In a plant cell there is an extra rigid layer that surrounds the membrane called the cell wall. This tough wall adds protection, structure, and stability to the cell.
What changes happen to a plant cell when you let a flower float in water for 24 hours?
The plant cell firstly takes up the water because of osmosis. Then they start to swell. The cell wall's rigid structure prevents the cell from bursting. The cell then becomes turgid which is swollen and hard. After that, the pressure starts to rise, which means no more water is able to enter the cell. The hydrostatic pressure works against osmosis next.
What changes happen to an animal cell when you let a flower float in water for 24 hours?
Differently from the plant cell the animal cell would start by taking up the water just like the other cell did. Thin the starts to swell and actually bursts. This cell bursts because there isn't a cell wall to protect it. All it has is a cell membrane which isn't strong enough.
What happens to plant cells when it loses water?
If plant cells lose too much water by osmosis then the cell membrane will eventually shrink. The membrane would shrink away from the cell wall. Loss of water makes the cell limp and eventually causes the membrane to shrink.
What happens to human blood cells in distilled water?
Distilled water is an example of a hypotonic solution. This means that it has less solute than a red blood cell. Our red blood cells would prefer if it was an isotonic solution which would allow water to leave and exit the red blood cell. This would mean the red blood cell would stay normal and not shrivel or expand. Since distilled water is a hypotonic it means that the solvent will follow the solute and move inside the cell which would cause it to burst.
7 characteristics of life
DNA
Cells
Growth and Development
Be able to reproduce
Metabolism
Homeostasis
Evolution and Adaptation
How eukaryotes gained mitochondria and chloroplasts? Why endosymbiosis benefited eukaryotic and prokaryotic cells?
Prokaryotic ribosomes are different than the eukaryotic ribosomes. Similarly to eukaryotic ribosomes, prokaryotic ribosomes build proteins to help other functions of the cell.
This organelle plays a critical role in the growth, survival, and reproduction of prokaryotic cells.
All prokaryotic cells have large quantities of genetic material in forms or DNA and RNA. Because prokaryotic cells, by definition, do not have a nucleus, a single large circular strand of DNA containing most of the genes needed for cell growth, survival, and reproduction is found in the cytoplasm.
As in all cells, the plasma membrane in prokaryotic cells is responsible for controlling what gets into and out of the cell.
It is very similar to the eukaryotic cytoplasm, except that it does not contain organelles.
Fun Facts about Cells
Groups of cells form tissues and systems.
The largest cell, a fertilized egg, is too small to be seen with the naked eye.
Red blood cells carry oxygen around the body. They are created inside the bone marrow of your bones.
Everything that has life – from humans to plants to animals to birds to microorganisms – everything is made of cells.
The longest cells in the human body are the motor neurons. They can be up to 4.5 feet (1.37 meters) long and run from the lower spinal cord to the big toe.
The first cell originated on Earth about 3.8 billion years ago.
The first ever cell that originated on Earth was a Prokaryotic cell. Eukaryotic cells later evolved from the Prokaryotic cells.
There are some nonliving objects on earth that are also made of cells, but those cells were once living. For instance, wood (dead cells of plants), dust in our house (a portion of that contains dead cells), wool, hair, leather (they were also living cells at one point).
Things like steel, iron, ceramics, aluminum etc. are not made of cells.
Cells are really tiny. So tiny that we cannot see them using our naked eyes. We usually need microscope to see those cells. However, exceptions are always there. Nerve cells or neurons that can stretch right up to our toes starting from our hips.
Though humans are made of Eukaryotic cells, there are are 200 different types of cells in human body. Yes, Eukaryotic cells have variants.
The size of a cell is usually determined by its diameter and not by the length. The usual size of a typical cell in human body can range anywhere between 10 µm and 100 µm (µm stands for micron, which is 1 millionth of a meter or 1 thousandth of a millimeter).
We have about 37.2 trillion cells in our body.
Approximately 50 billion to 70 billion cells in human body die every single day.
Tissues are formed by a number of cells. Again, a number of tissues form an organ. A number of organs actually form a system.
There are 23 pairs of chromosomes inside a single cell. That means, there are 46 chromosomes inside a single cell in human body!
There is clear evidence that mitochondria and chloroplasts were once primitive bacterial cells. This evidence is described in the endosymbiotic theory. Symbiosis occurs when two different species benefit from living and working together. When one organism actually lives inside the other it's called endosymbiosis. The endosymbiotic theory describes how a large host cell and ingested bacteria could easily become dependent on one another for survival, resulting in a permanent relationship. Over millions of years of evolution, mitochondria and chloroplasts have become more specialised and today they cannot live outside the cell. According to the Endosymbiotic Theory the first eukaryote evolved from a Symbiotic relationship between 2 or more prokaryotic cells. Smaller prokaryotic cell were engulfed by larger prokaryotic cells. The smaller cells or as we know call them endosymbionts benefited from the relationship by getting a safe home and nutrients. The larger cells that we know call hosts benefited by getting some of the organic molecules or energy released by the endosymbionts. Eventually the endosymbionts evolved into organelles of the host cell. After that neither could live without the other. Someof the endosymbionts were aerobic bacteria. They were specialized to break down chemicals and release energy. These evolved into the mitochondria of a eukaryotic cell. Some of the cells wer cyanobacteria. They were specialized for photosynthesis. They eventually evolved into the eukaryotic organelle called chloroplasts.
Not all cells have DNA
Some human cells have 47 chromosomes. This is diagnosed as Down's Syndrome.
Evidence for Endosymbiotic Theory
Mitochondria and chloroplasts have striking similarities to bacteria cells. They have their own DNA, which is separate from the DNA found in the nucleus of the cell. And both organelles use their DNA to produce many proteins and enzymes required for their function. A double membrane surrounds both mitochondria and chloroplasts, further evidence that each was ingested by a primitive host. The two organelles also reproduce like bacteria, replicating their own DNA and directing their own division. These observed characteristics of both, mitochondria and chloroplast, are heart of the Endosymbiotic Theory.
Equilbruim
The condition in which all acting influences are balanced or canceled by equal opposing forces, resulting in a stable system.
In a Eukaryotic cell DNA is found within the nucleus on the chromosomes.
A plant cell diagram:
An aniimal cell diagram: