Cellular Geography Flashcards
What are the 7 Characteristics of life?
- Organisms are complex and organized
- Living organisms can take energy from he environment and change it from one form to another
- Organisms are homeostatic - internal body and structures are regulated within parameters
- Living things respond to stimuli
- Living things reproduce themselves by making exact copies of themselves
- Organisms grow and develop
- Life adapts
What are the 3 points to cell theory?
- All living organisms are composed of cells or are cells
- Cells are functional units of life
- Cells arise only from preexisting cells by a process of division
How do you study cells biochemically?
Blend whole cells and put them through a centrifuge separating heavy and light components
What is a cell?
Simplest collection of matter which has all the properties of life
What are the 2 basic kinds of cells?
Prokaryote and Eukaryote
What does prokaryote mean?
Before nucleus
Where do prokaryotes keep their genetic info?
In the nuclei (genetic information area)
-lacking membrane to be called a nucleus
What are the visible components of the prokaryote?
Plasma membrane Ribosomes Nucleoid Cytoplasm Cell wall Pili Flagella Mesosomes Photosynthetic membranes
What is the order of the outside layers of a prokaryotic cell?
plasma membrane
cell wall (for shape)
capsule (gooey material on the outside)
What is one micron?
1000th of a mm
What does Eukaryote mean?
True nucleus
What are the 4 categories of eukaryotes ?
Protista
Fungi
Planta
Animalia
What are the visible components of a eukaryotic cells?
plasma membrane cytoplasm nucleus ribosomes organells endomembrane system cytoskeleton cell wall cell matrix flagella
What is the cytoskeleton?
Proteins making up and supporting the matrix
What is the cell matrix?
Area outside of the cell
What features to plant cells have that animal cells do not?
- Cell wall for strength
- Central Vacuole
- Chloroplasts
- Plasmodesmata: pore so that cells can connect and support each other
What is cytoplasm?
Material between the plasma membrane (cell membrane) and the nuclear envelope
-gel like consistency
What is the cytoplasm composed of?
80% water Nucleic acids Protein Lipid Carbs Pigments
What is the smallest organelle?
Ribosomes
What are ribosomes made of?
Protein and rRNA
What do ribosomes do?
The 2 subunits carry out protein synthesis
What does the rough Endoplasmic reticulum do?
Covered in ribosomes and make components destined for the cell membrane
What does the smooth Endoplasmic reticulum do?
Has a lot of enzymes present and detoxifies drugs
What is the endomembrane system?
All internal membranes within the cell
What are the membranes included in the endomembrane system?
Plasma Nuclear ER membrane Vesicles Lysosomes GA Vacuoles
What makes a plasma membrane a bilayer?
Only if it has associated proteins on it
What are examples of cells with none, 1 and 2 nuclei
Red blood cells (extra room to carry O2)
Fungal cells
Muscle Cells (faster innervation for faster reflex)
What happens then a compound is finished at the ER?
It is packaged and sent to the GA to finish it
What are lysosomes?
Membrane bound sac of hydrolytic enzymes that digest macromolecules
-only work within a certain pH
What are vacuoles?
Membrane bound sacs with 3 functions:
- Food vacuoles (arise from phagocytosis)
- Contractile vacuoles (pupo excess water out via osmosis)
- Central vacuoles (in plant cells)
What is the name of the membrane surrounding the central vacuole?
Tonoplast
-selective membrane
What are some of the functions of the central vacuole?
- Stockpiling proteins or inorganic ions
- Depositing metabolic byproducts
- Storing pigments
- Storing defensive compounds against herbivores
80% of which organelle takes up a plant cell?
Central Vacuole
What is mitochondrial role?
Site of cellular respiration generating ATP from the catabolism of sugars and fats and other fuels in the presence of O2
What is the chloroplasts role?
Site of photosynthesis using light and CO2 to build sucrose
What are the folds called in the mitochondria?
Cristae
Do chloroplasts have a double membrane?
yes
Which organelles are autonomous?
Mitochondria and Chloroplasts because they are not under the control of the nucleus
What is the cytoskeleton?
Network of fibres extending throughout the cytoplasm
- shape maintained via protein elements to give the cell shape
- organizes activités of he cell
Can the cytoskeleton be reorganized ?
Yes, cell can take them apart and rearrange them
How do organelles move around the cell?
On the microtubule tracks
What are cilia?
Beating arms of a cells to help it move
-large amount on the cell
What are flagella?
Undulatory movement, like a whip for movement
What is cytoplasmic streaming?
In plant cells (and other) actin-myosin interactions and sol-gel transformations drive cytoplasmic streaming
Which is thicker, plant cell wall or plasma membrane?
Cell wall is thicker
What is the cell wall made of?
Cellulose fibres
Pectin (glue between cells)
What are plasmodesmata?
Pores connecting cells and help in communication
-virus can take advantage of this
What are the 3 ways in which cells can connect together?
- Anchoring
- Tight Junctions
- Gap Junctions
