Science vocab Flashcards
Scientific theory
Explains WHY things happen the way they do. They need to be constantly challenged and confirmed especially when new data appears. They do not become laws as they do not explain WHAT. The development of theories often lead to the formation of laws.
Scientific law
They explain WHAT will happen.
They are more resistance to challenges than theories, but the to can change. They are not just grown up theories as they do not explain WHY. Laws are often formed through the development of theories.
The Cell Theory
All organisms are composed of one or more cells. The cell is the basic unit of structure and organization in organisms.
Cells arise from pre-existing cells. First developed by Schleiden and Schwann. The third statement was a source of disagreement between the two. Virchow provided research to settle this debate, but the research he took credit for was actually Remak’s.
Cells
The smallest unit of life. All living things, organisms, are made of them. (Schleiden plants & Schwann animals). Different tissues in the body of a many celled organism are made of the similar types of cells.
Anton Van Leeuwenhoek
Scientist used an early example of a microscope of his own design to be the first to study cells.
He looked at bacteria (he called them animalcules) from his teeth scrapings.
His work was widely circulated and gave birth to the study of microscopic life.
Microscope technology made this possible.
Robert Hooke
Scientist who coined the term “cell” after observing a sample of cork under an early microscope. The individual compartments of the cork sample reminded him of the rooms or cells in a monastery.
Endosymbiotic Theory
Endosymbiosis is when one organism lives inside another organism.
The Endosymbiotic Theory states that the mitochondria and chloroplast in other cells were once their own organisms that were ingested by a large organisms.
This theory explains the origin of more evolved cells. Mr. Kirk calls it the “Kirby Effect.”
Unicellular vs. Multicellular Organism
Unicellular organisms, living things, are made of only ONE cell. Examples of unicellular organisms- Euglena, Escherichia coli, Diatoms, Protozoa, Protista, Streptococcus, Pneumococci, and Dinoflagellates. Multicellular organisms, living things are made of MANY cells. Examples of multicellular organisms- Nearly all of the living things we see everyday likes cats, dogs, trees, daffodils, you, and me.
Membrane
The thin layer that forms the outer boundary of a cell or of an internal cell compartment.
Prokaryotic Cells
Are the most basic type of cell. They do not have a true nucleus or membrane-bound organelles. This type of basic life has existed on Earth for roughly two billion years.
Bacteria
A member of a large group of unicellular organisms which have cell walls but lack organelles and an organized nucleus.
They are examples of the most basic form of life as they are made of prokaryotic cells.
Some can cause disease, but many are vitally important to our health.
Eukaryotic Cells
Are more advanced cells.
They contain membrane-bound organelles such as a nucleus, mitochondria, and an endoplasmic reticulum. The blob cell in the video evolved from prokaryotic to eukaryotic.
Organelles
Are structures within a cell that have one or more specific jobs to perform.
They are like simplified versions of the organs in your body. Examples- chloroplast, mitochondria, ribosomes, nucleus.
Nucleus
A large membrane-bounded organelle that contains the genetic material (DNA).
Often referred to as the “control center” of the cell. Present in eukaryotic cells only.
Chloroplasts
is an organelle in eukaryotic cells that is photosynthetic. It can gather the Sun’s energy and make sugar. According to endosymbiotic theory it was first an ancient photosynthetic bacteria, a prokaryotic cell that was its own organism.
