Chapter 22 The Basic Unit Of Life - Cells Flashcards
Organism
Individual living thing, such as a plant or an animal
Biology
The study of life and living things
Five features of living things
- Use energy
- Develop and grow
- Maintain themselves
- Reproduce
- Evolve
Four kinds of macromolecules
- Carbohydrates
- Lipids
- Proteins
- Nucleic acids
Carbohydrates
Store energy in living things . Some provide structure
Lipids
Not soluble in water. Store energy for long periods of time and release more energy
Proteins
Provide structure, allow muscles to move, and carry oxygen through the body. Made up of amino acids. ( only 20 amino acids )
Nucleic acids
Store genetic information called DNA and RNA in living organisms. Strands made up of sugar-phosphates and a series if nitrogenous bases
Nitrogenous bases
- adenine
- guanine
- thymine
- cytosine
Cells
Basic unit of all living things
Two types of cells
- Prokaryotes
2. Eukaryotes
Differences between pro. and eu.
Pro has no nucleus , has been around longer, typically smaller. Have an outer cell wall. Are only bacteria. Eu is the opposite . Eu have organelles. Store DNA in nucleus
Organelles
Structures that have specific functions in the cell
Chromosomes
Circular or linear structures
Light microscopes
Sending light to a specimen and then through several lenses. The lense refract the light magnifying the image of the specimen . Magnify (10-6m) in size
Electron microscopes
Electron beans are directed to the specimen. Electric and magnetic fields are used to focus the beam and magnify images . Magnify a (10-9m) in size .
Cell membrane
Separate the inside from the outside of the cell. Controls what goes in and out
Cell wall
Plants have a rigid cell wall . Animals have no cell wall. The cell wall helps protect and support the plant cell
Nucleus
A structure that contains the cell’s DNA .
Cytoplasm
Out the nucleus . Crisscross end by numerous fibers . Contains many organelles
Cytoskeleton
Helps hold the shape of the cell.
Ribosomes
Build protein . Some are attached to the RER
Rough endoplasmic reticulum
Some of the cell’a proteins are assembled here.
Smooth endoplasmic reticulum
Builds membrane
Golgi apparatus
Called the ‘post office ‘ . Revivers products from the endoplasmic reticulum , modifies them, and then packages them for delivery.
Lysosomes
In animal cells, break down organic molecules . Called ‘garbage disposals’
Mitochondria
Obtains energy for cells to use . They break down food molecules .
Chloroplast
In plant cells captures energy from sunlight to build organic molecules
Vacuole or vesicles
Stores materials such as water or nutrients
The cell membrane three molecules
- Phospholipids
- Proteins
- Carbohydrates
Phospholipids
Molecules with ‘heads’ and ‘tails’. The heads are hydrophilic and the tails are hydrophobic .
Hydrophilic heads
Are attached to the watery environment inside and iutside the cell.
Hydrophobic
Stay away from the watery environment
Proteins = membrane proteins
Do multiple things such as transporting molecules in and out if the cells. Other help control the reactions that occur in cells . Others help cells communicate with each other
Carbohydrates
Are attached to the membrane proteins and phospholipids on the outer surface of the cell membrane. Allow different cells to recognize each other.
