Lesson 2: Cell biology Flashcards
What is stuff made of?
All ordinary matter in the universe is made of atoms
- atoms are made of protons, neutrons, and electrons
What happens when a molecule is created, broken apart, or modified?
A chemical reaction
- these reactions often just involve a change in the position of electrons in the molecule
What does the likelihood of a chemical reaction depend on?
The temperature
- the shape of the molecule will determine the chemical reaction: pushing apart or together
What is an ion?
When a molecule or single atom has an electric charge
- ions form ionic (electric) bonds with each other
What are molecules that are held together by ionic bonds called?
Salts
- ionic bonds typically break apart (dissolve) in water
What are the characteristics of the mitochondria and what does it do?
It has 2 membranes, has its own DNA, copies its DNA and splits, etc.
- it converts sugar to the ATP molecule
What type of cell started evolution on Earth?
Eukaryotic cells
- they formed multicellular organisms, forming the structure and function of life (animals)
What are the 6 main elements of cells (of life on Earth)?
Carbon
Hydrogen
Nitrogen
Oxygen
Phosphorus
Sulfur
What are the 5 components of the cells? (CHNOPS elements combinations)
- Water
- Sugar
- Fat (lipid)
- Nucelic acid
- Amino acid
T/F: Amino acids make up 50% of a cell
True. Long strings of amino acids are called proteins
- 15% sugar (carbohydrates)
- 10% fat (lipid)
- 15% nucleic acids (RNA & DNA)
- 10% other organic molecules
What is RNA?
Refers to a type of nucleic acid, specifically a ribonucleic acid
- some strands of RNA can catalyze chemical reactions: it is then called a ribozyme
What is it called when a strand of RNA can catalyze a chemical reaction?
A ribozyme
What is it called when a protein can catalyze a chemical reaction?
An enzyme
What are tRNAs?
Small strands of RNA that can hold an amino acid, which can be easily strung together to make new proteins
What is a ribosome? What is its function?
A molecular machine. It creates new proteins by linking together the amino acids held by tRNA molecules
- function: stringing together the amino acids held by tRNA in the order dictated by the genetic code, thus creating proteins