Chapter 4 Cell Structure Flashcards
Why are cells small instead of large?
many small cells= more surface area
Every cell has (4)
Plasma membrane (barrier)
chromosomes (store DNA)
ribosomes (make proteins)
cytoplasm (interior of cell)
What are the two major types of cells
Prokaryote (small, simple, bacteria)
Eukaryotic (has a nucelus, more complex, larger)
Where is DNA contained within prokaryotic cells?
Nuceloid region
How do prokaryotes move around?
Pili or flagella or something like that
What organelles or features are present in Animal cells but not plant cells?
- Lysosomes
- Centrioles
- Flagella
What organelles or features are present in plant cells but not animal cells
- Chloroplasts
- Rigid cell wall
- Central vacuole
What is the plasma membrane made of?
a phospholipid bilayer
What are some characteristics of the plasma membrane?
- responsible for transport of molecules
- many cell reactions take place here
- proteins, cholesterol and phospholipics
The nucleus is seperated from the cytoplasm by the _______
Nuclear envelope
What is the name of the region where ribosomal DNA is synthesized?
Nucleolus
In what form is DNA stored in Nucleus?
DNA +proteins +chromatin
Chromatin condenses to from chromosomes
What is the function of ribosomes?
Ribosomes carry out protein synthesis
What is the endomembrane system?
It is a collection of membranous organelles
What is the endoplasmic reticulum?
continuous membrane with nuclear envelope
What is the function of the rough ER?
Manufactures more membrane
whar is the function of smooth ER?
synthesizes lipids
stores calcium
What is the function of the golgi apparatus?
Receive and modify products from the ER and send these products onto other organeelles (primarily deals with proteins)
What is the function of lysosomes?
Hydrolyzes proteins, fats, polysaccarides, and nucleic acids, pumps H+ into lumen tomaintain pH
What is the function of a vacuole?
lysosomal and storage functions
some digest materials (food vacuoles)
What organelle is the site of celliular respiration?
mitochondra
What is the function of the Mitochondira?
-harvests chemical energy from frood and stores it as ATP
What is the function of peroxisomes?
Peroxisomes have two functions: break down fatty acids to be used for forming membranes and as fuel for respiration; and transfer hydrogen from compounds to oxygen to create hydrogen peroxide and then convert hydrogen peroxide into water. They protect the cell by containing these potentially harmful reactions
What two structures are responsible for cell support, movement, and communications
cytoskeleton
cell-cell junctions
What are the functions of the cytoskeleton
- Establishes and maintains cell shape
- Provides mechanical strength
- locomotion
- chromosome seperation during cell division
- intracellular transport of organelles
What 3 types of fibres is the cytoskeleton composed of?
- Microfilaments: made of actin, enable cells to change shape and move
- Intermediate filaments: reinforce cell and anchor certain organelles
- Microtubules: give cell rigidity, provide anchors, acts as tracks for organelle movement
What is the function of cilia or flagella
Locomotion that protude from some cells (sperm)
What makes locomotor appendages move?
When microtubules bend
What is the extracellular matrix made of in animal cells?
Glycoprotein
