Module 1 Flashcards
Cell
The smallest and simplest unit of life that exists.
Cytoplasm
The space between the cell membrane and the nucleus.
Cytosol
Jelly-like internal fluid environment of a cell (cytoplasm minus organelles). Contains water, dissolved ions, and molecules.
Prokaryote
A cell without a nucleus.
Eukaryote
A cell with a nucleus.
DNA
Deoxyribonucleic Acid. Stores the genetic information of the cell. Has a double helix due to the hydrogen bonding between the nucleotide pairs (A-T) and (G-C).
RNA
Ribonucleic Acid.
Protein
Molecules that provide structure and do much of the work of the cell.
Transcription
The synthesis of RNA from a DNA template.
Translation
The synthesis of proteins from an RNA template.
Vacuole
A membrane-bound organelle present in some cells, including plant and fungal cells, that contains fluid, ions, and other molecules. It absorbs water and contributes to turgor pressure.
Lysosome
Membrane bound sacs containing digestive enzymes.
Cytoskeleton
Internal protein scaffolding. Can be remodelled quickly.
Cell/Plasma Membrane
Separates the living material within the cell from the nonliving environment around it. Controls the movement of materials into and out of the cell.
Cell Wall
A structural layer external to the cell membrane that helps maintain the shape and internal composition of the cell. Present in plants, fungi, many protists, archaea, and bacteria.
Organelle
Any one of several compartments in eukaryotes that divides the cell contents into smaller spaces specialized for different functions.
Nucleus
The compartment of the cell that houses the DNA in chromosomes.
Nuclear Envelope
Defines boundary of the nucleus and contains an inner and outer membrane with nuclear pores.
Mitochondria
Produce energy in the form of ATP.
Chloroplasts
An organelle in photosynthetic eukaryotes that converts the energy of sunlight into chemical energy by synthesizing carbohydrates via photosynthesis.
Endoplasmic Reticulum (ER)
Complex network of interconnected tubules and flattened sacs. Involved in protein and lipid synthesis.
Rough Endoplasmic Reticulum (RER)
Have ribosomes for protein synthesis.
Smooth Endoplasmic Reticulum (SER)
Lacks ribosomes. Lipid synthesis.
Golgi Apparatus
Modifies proteins and lipids produced by the ER, sorts proteins and lipids to their destination, and adds carbohydrates to proteins and lipids.
Ribosome
A complex structure of RNA and protein that synthesizes proteins from amino acids as directed by the sequence of mRNA.
ATP
Adenosine Triphosphate. Provides chemical energy which allows cells to carry out all sorts of work such as growth, division, and moving substances into and out of the cell.
Model Organism
Non-human species that are used to understand biology. Ex. bacteria, yeast, plant, fly, worm, and mouse.
The Cell Theory
1) All organisms are made up of cells.
2) The cell is the fundamental unit of life.
3) Cells come from preexisting cells.
The Central Dogma
DNA —Transcription—> RNA —Translations—> Protein
Metabolism
The chemical reactions occurring within cells that convert one molecule into another and transfer energy in living organisms. Required to sustain life.
Domains of Life
1) Bacteria
2) Archaea
3) Eukarya
Gene
The DNA sequence that corresponds to a functional product, such as a protein.
DNA Replication
The process of duplicating a DNA molecule, during which the parental strands separate and new partner strands are made. It allows for genetic information to be passed from cell to cell or from an organism to its offspring.
Mutations
Any heritable change in the genetic material. Can result from an error in replication or a mutagen such as radiation or chemicals.
Nucleoid
In prokaryotes, a cell structure with multiple loops formed from supercoils of DNA.
Flagella (Flagellum)
Structures that extend from the surface of bacteria which allows them to move.
Theory
An educated guess that has been tested multiple times by various people leading to the same conclusion.
Robert Hooke (1665)
First discovered cells by looking at a piece of cork. He saw the cell walls of dead cells.
Anton van Leeuwenhoek (1673-1700)
Saw “animalcules” in pond water via an early light microscope.
Types of Microscopes
1) Light
2) Electron
3) Fluorescence
Schleiden (1838)
A German botanist, found that all plant tissues are made up of cells and that plant embryos arise from a single cell.
Schwann (1838)
A German zoologist, came up with the same conclusion as Schleiden about animals.
Virchow (1885)
A German zoologist, added the third rule to The Cell Theory.
Exceptions to the Cell Theory
1) Viruses
2) Viroids
3) Prions
Plasmids
Small DNA molecules separate from the chromosomal DNA. Can replicate on its own and are usually found in bacteria.
Bacteria
Prokaryotes that usually have plasmids and a cell wall surrounding the cell membrane.
Archaea
Prokaryotes that usually have isoprenoid cell membranes and a cell wall. They often inhabit extreme environments.
Protists
Usually single cells. Can form colonies. A very diverse group. Ex. algae, water molds, slime molds, and protozoa.
Fungi
Have chitin in cell walls. Are heterotrophs, depend on other molecules for energy by absorbing it directly from the environment. Ex. yeasts, rusts, smuts, mildeus, molds, and mushrooms.
Plants
Are multicellular and have cell walls made of polysaccharides. Have large vacuoles filled with water. Have intercellular connections called plasmodesmata. Are autotrophs meaning that they produce their own food (chloroplasts convert sun’s energy into chemical energy).
Animals
Are multicellular and do not have cell walls. Are heterotrophs, gain energy and carbon from other molecules.
Microfilament
A double helix of actin monomers.
Microtubule
A hollow tube formed from tubulin dimers.
Intermediate Filament
A strong fiber composed of intermediate filament protein subunits.
Peroxisomes
Carry out the oxidation of fatty acids and detoxification of certain toxic compounds ex. hydrogen peroxide.
