CHAPTER 4: General Features of Cells - Coggle Diagram
CHAPTER 4: General Features of Cells
Overview of Cell Structure
Simple cell structures
Two categories of prokaryotes:
Very abundant in environment and our bodies
Vast majority are not harmful to humans
Some species cause diseases
Also small cells, around 1-10 micrometers in diameter.
Less common than bacteria.
Often found in extreme environments.
Typical bacterial cell
Inside the plasma membrane:
Cytoplasm: contained within plasma membrane
Nucleoid Region: where DNA is located.
Ribosomes: synthesize proteins
Outside the plasma membrane:
Cell wall: provides support and protection
Glycocalyx: traps water, gives protection, help evade immune system
Appendages: pilli (attachment), flagella (movement)
More complex cells
DNA enclosed within membrane-bound nucleus
Internal membranes form organelles
DNA is housed inside membrane-bound nucleus.
Each has a unique structure and function
Shape, size and organization of cells vary considerably.
Differences between species.
Differences between specialized cell types.
Region of a cell that is outside the cell organelles but inside the plasma membrane.
Cytoplasm includes everything inside the plasma membrane
Molecular Synthesis and Breakdown
Sum of all chemical reactions by cells
Anabolism: synthesis of cellular molecules and macromolecules
Catabolism: Breakdown of a molecule into smaller components
The Nucleus and Endomembrane System
A network of membranes enclosing the nucleus, endoplasmic reticulum, golgi apparatus, lysosomes, and vacuoles.
Also includes Plasma Membrane
May be directly connected to each other or pass materials via vesicles.
Network of membranes that form flattened, fluid-filled tubules or cisternae
ER membrane encloses a single compartment called the ER lumen.
Rough Endoplasmic Reticulum (Rough ER)
Studded with ribosomes
Involved in the synthesis of proteins and sorting.
Smooth Endoplasmic Reticulum (Smooth ER)
Does not contain ribosomes.
Detoxification, carbohydrate metabolism, calcium balance, synthesis, and modification of lipids.
Also called the golgi body, golgi complex, or simply golgi.
Stack of flattened, membrane-bound compartments.
Vesicles are used to transport materials between each stacks of flattened compartments.
Three overlapping functions:
Contain acid hydrolases which performs hydrolysis
Many different types of acid hydrolases to break down proteins, carbohydrates, nucleic acids, and lipids
Also known as the recycling of worn-out organelles through a process called as endocytosis.
Functions are extremely varied, because they differ among cell types and environmental conditions.
Types of Vacuoles
Found in plants, used for storage and support.
Found in protists, used for expelling excess water.
Found in protists and white blood cells, used for degradation or breaking down of molecules.
Chromosomes are composed of DNA and proteins and are also known as chromatids.
Where ribosome assembly occurs.
Catalyzes certain reactions that break down molecules by removing hydrogen or adding oxygen
it is a by product of H20
It is the boundary found between the cell and the extracellular environment
Functions contain membrane transport in and out of the cell, cell signaling using receptors, and cell adhesion.
Primary role is to make ATP or energy
Also involved in the synthesis, modification, and breakdown of several types of cellular molecules.
Contains their own DNA, divided by binary fission
Have the ability to grow and divide to reproduce themselves without the help of other molecules or organelles.
However, they are not completely autonomous because they depend on the cell for synthesis of other internal components
Found in the photosynthesis of plants
Captures light energy and use some of that energy to synthesize organic molecules such as glucose
Found nearly in most species of plants and algae
Also contains their own DNA and are divided by binary fission.
Protein Sorting to Organelles
To ensure that the proteins are sorted to the right destination.
For Er, Golgi, Lysosomes, Vacuoles, Plasma membrane, and secreted proteins.
Beings in cytosol during translation.
Involves sorting signals and vesicle transport.
Most proteins for nucleus, mitochondria, chloroplasts, and peroxisomes.
Synthesized in cytosol and sorted later.