Cell Biology, more in depth
What is a cell ?
What are some of the types of cells?
What are cells made of and what are the various parts of cells?
How do cells work and what are some possible cell jobs?
Carbon is an atom from the periodic table of elements that is found in organic molecules, it can bond with many atoms at the same time and forms chains that create bigger molecules.
Atoms have neutrons, protons and electrons:
Protons are positively charged subatomic particles in the nucleus of an atom
Neutrons are electrically uncharged subatomic particles found in the nucleus of an atom, neutrons are neutral
Nucleus is the center
Electrons are negatively charged subatomic particles, they are smaller than other subatomic particles and exist in a cloud around the nucleus of an atom in, valence shells, they orbit the nucleus
Valence shells are orbits around the nucleus, they can hold a certain number of electrons and the spaces for electrons fill from the inside out.
By looking at how many protons, neutrons, and electrons there are in an atom we can draw Bohr Diagrams.
In the diagram below you can see how many electrons can be held in each valence shell:
Noble gases such as helium and neon have no ability to bond with anything, every spot where a bond could exist is taken up.
Carbon has space for four bonds because the outer valence shell can have eight electrons and carbon has four outer electrons, Neon on the other hand, is all full.
Helium has two outer electrons on a valance shell that can hold two electrons, it cannot bond with anything. Hydrogen on the other hand, has one electron and can bond with one thing, without this, H2O, water, would not be possible and there would be no life as we know it.
Carbon and hydrogen form covalent bonds, this means that they share
electrons and fill their available spaces
In an ionic bond there is an electrochemical attraction between atoms of opposite charges and one atom gives away their electrons, those bonds are stronger and are found in metals.
Many of the foods we eat form ionic bonds, there are alkaline earth metals that we need for proper nutrition, examples are: calcium, sodium, magnesium...
We need salt, just not too much, salt is sodium chloride and has an ionic bond:
Sodium, from salt, is Na on the periodic table of elements, it is an alkali metal, the elements are organized into element families and groups and periods based on their properties
Carbon based macroMolecules
Let's look at some macromolecules: lipids, carbohydrates, proteins, and nucleic acids
they contain hydrocarbons, chains of hydrogen and carbon:
generally repel water
We need lipids to form phospholipids:
Phospholipids are in the cell membrane of cells:
Cells have a cell membrane to keep contents safe
an organic molecule that is made up of one or more sugars
one carb sugars are monosaccharides
multiple linked saccharides are polysaccharides
and organic molecule made up of linked amino acid subunits,
Proteins are a combination of 21 amino acids, DNA has a code for what amino acids to link and in what order
There are primary, secondary tertiary, and quaternary structures:
organic molecules made up of linked nucleotide subunits
DNA and RNA are Examples of nucleic acids
Inside the cell
Cell Contents are Organelles
tiny cellular structures that perform specific functions within a cell
Click on the organelles to learn more:
The cell nucleus has chromosomes, they are bundles of DNA
Types of cells
cells that have no internal membranes, no organelles
cells with membrane bound organelles and a nucleus
plants, animals, fungi
Plant cells have a cell wall and chloroplasts that photosynthesize
SIngle cell beings
Many living beings are multicellular, here are some single cell beings:
Diatoms, single cell eukaryotes:
they look like glass
they are protozoans
single celled eukaryotes
Fungi, there are single and multicellular eukaryotic cells
Prokaryotes vs Eukaryotes
How PENICILLIN was discovered
Gram POSITIVE vs gram negative bacteria
Gram staining is a common technique used to differentiate between two groups of bacteria based on cell wall composition
Penicillin targets the peptidoglycan of bacterial cell walls.
Some antibiotics are protein synthesis inhibitors, they inhibit prokaryotic ribosomes in the bacteria
Ribosomes are needed to produce proteins
Author: Jazmin Gannon
A place to grow