Organelle Structure and Function

Question 1

Theory of Endosymbiosis

Answer 1

MItochondria and chloroplatss were once independent prokaryotes who eventually joined larger cells

Question 2

Prokaryotic Cells

Answer 2

Small ribosomes
No cytoskeleton
Nor organelles (but has a nucleoid region)
Plasmid sometimes present
Anaerobic and aerobic metabolism
Flagella made of the protein flagelin

Question 3

Eukaryotic Cell

Answer 3

Nucleus and organelles present
Chromosomes long and bound with histones
Multicellular
Can be autotrophic or heterotropic

Question 4

Flagella and Cilia in Eukaryotes

Answer 4

Made of tubulin

Arrange 9 +2

Question 5

Autotrophs

Answer 5

Photoautotrophs
- Use photosynthesis to make food from sunlight

Chemoautotrophs
- Use chemosynthesis to make food from inorganic substance

Question 6

Obligate Anaerobes

Answer 6

Need absence of oxygen to survive

Question 7

Obligate Aerobe

Answer 7

Need oxygen to survive

Question 8

Facultative Anaerobe

Answer 8

In absence of oxygen, can switch from aerobe to anaerobe

Question 9

Ribosomes

Answer 9

On ER- proteins made here leave cell

In cytoplasm- proteins made here used within cell

Question 10

SER

Answer 10

Synthesis of steroid hormones and lipids
Stores Ca in muscle cells
Also stores detox drugs and poisons

Question 11

Peroxisome

Answer 11

In both plant and animal cells
Convert hydrogen peroxide into water using catalase
In liver, detox alcohol

Question 12

Glyoxysomes

Answer 12

Germinating seeds of some plants have a specialized variation of peroxisome

Question 13

Transport vacuole

Answer 13

Move materials between organelles or between organelles and PM

Question 14

Central vacuole

Answer 14

Most of plant cell interior
Cause turgidity when fully filled to maintain rigidity

Also store nutrients, and carry out functions performed by lysosomes in aniamls cells

Have a specialized membrane (tonoplast)

Question 15

Merge Vacuole

Answer 15

Merge with lysosomes which break down food

Question 16

Storage vacuole

Answer 16

Plants store starch, pigments, and toxic substances (i..e nicotine)

Question 17

Contractile vacuoles

Answer 17

In single celled organisms that collect and pump excess water out of the cell

Utilizes active transport

Found in protista (amoeba, paramecia) and organisms in a hypotonic environment

Question 18

Cell Wall in Plants

Answer 18

Cellulose

Question 19

Cell Wall in Fungi

Answer 19

Chitin

Question 20

Cell Wall in Bacteria

Answer 20

Peptidoglycans

Question 21

Cell Wall in Archea

Answer 21

Polysaccharides

Question 22

Extracellular Matrix

Answer 22

Animal cells secrete collagen to form ECM

Found in area between adjacent cells

Fibrous structural proteins, adhesion proteins, polysaccharides

Made of collagen mainly
Also see integrin+fibronectin, laminin

Question 23

Function of ECM

Answer 23

Provides mechanical support

Helps binds adjacent cells

Question 24

Integrin+Fibronectin

Answer 24

Network of collagen and proteoglycans (glycosylated proteins) connected to integrins ( TM protein) in the cell membrane via fibronectin (glycoprotein)

Question 25

Laminin

Answer 25

Also seen in ECM | Acts similar to fibronectin (adhesion protein, anchors cell to collagen or proteoglycans)

Question 26

Focal Adhesions

Answer 26

Connection of ECM to actin filaments in cell

Question 27

Hemidesmosomes

Answer 27

Connect 1 cell to basal membrane | Connection of ECM to intermediate filaments (i..e keratin)

Question 28

Plastids

Answer 28

Found in plant cells Chloroplasts Leucoplasts Chromoplasts

Question 29

Leucoplasts

Answer 29

Can specialize to store starch/lipid/protein as amyloplasts/elaioplasts,proteinoplasts Can also serve general biosynthetic functions

Question 30

Chromoplasts

Answer 30

Store carotenoids

Question 31

Microtubules

Answer 31

Made of tubulin | Found in flagella, cilia, spindle fibers during division

Question 32

Microfilaments

Answer 32

Made of actin | Used for cellmovement and muscle contraction

Question 33

Intermediate Filaments

Answer 33

Maintains and supports cells | i.e. Keratin found in hair

Question 34

Types of Active Transport

Answer 34

``` Exocytosis Endocytosis (phagocytosis, pinocytosis, receptor mediated endocytosis) ```

Question 35

Phagocytosis

Answer 35

Engulfing of particles (i..e white blood cells)

Question 36

Pinocytosis

Answer 36

Uptake of dissolved particles | Cell drinking

Question 37

Receptor mediated encodytosis

Answer 37

Form of pinocytosis | Specific molecules in the fluid around the cell binds to receptors

Question 38

Aquoaporin

Answer 38

Type of porin found in plant roots and kidneys, allowing water to flow more rapidly than diffusion

Question 39

Plasmolysis

Answer 39

MOvement of water out of a cell resulting in the collapse of the cell

Question 40

Dialysis

Answer 40

Diffusion of solutes across a selective membrane

Question 41

Bulk Flow

Answer 41

Movement of a fluid in one direction in an organism Always from one source i.e. Blood flow around the body

Question 42

Cell Junctions

Answer 42

Anchor cells to each other or provide passageways for exchange of materials

Question 43

Desmosomes

Answer 43

Anchoring junction Connects 2 cells together Provides stability and holds things together

Question 44

Tight Junction

Answer 44

Seal, prevents things from passing from cell to cell | Found in digestive tract to get things into bloodstream

Question 45

Gap Junctions

Answer 45

Allows ions and small molecules to pass from cell to cell | How the heart cells coordinate together to contract in unison

Question 46

Plasmodesmata

Answer 46

Gap junctions of plant cells

Question 47

Quorum Sensing

Answer 47

Bacteria secrete molecules ot communicate

Question 48

Paracrine Siganlling

Answer 48

Local messages/signals are released (i.e. GF) | Includes synaptic signalling (NT release)

Question 49

Long Distance Siganling

Answer 49

Endocrine system

Question 50

Hydrophilic Messengers

Answer 50

First messenger or ligand Binds to receptor Message carried on inside by second messenger

Question 51

Cytoplasmic receptor

Answer 51

Receptors inside cell that bind to smaller, nonpolar hydrophobic ligands that can diffuse through PM i.e. Steroids, thyroid hormone, NO

Question 52

Tonicity

Answer 52

Ability of an extracellular solution to make water move into or out of a cell by osmosis Solution's tonicity is related to its osmolarity

Question 53

Osmolarity

Answer 53

Total concentration of all solutes in the solution

Question 54

Plasmyolysis

Answer 54

Cell membrane shrinks and detaches from cell wall Occurs when plant cells are in hypertonic solution (high concentration of solute outside cell)

Question 55

Plant Cells in Hypotonic Solution

Answer 55

Water moves into cell | Cell wall counteracts osmotic pressure to prevent swelling and lysis

Question 56

Golgi

Answer 56

Packages and modifies proteins Transports lipids around cell Produces lysosomes

Question 57

Structure of Eukaryotic Ribosome

Answer 57

60S + 40S= 80 S

Question 58

Structure of Prokaryotic Ribosome

Answer 58

50S + 30S= 70 S

Question 59

Polar Microtubules

Answer 59

Nuclear division Connect to push MTOC to opposite ends of cell

Question 60

Astral Microtubules

Answer 60

Extend to cell membrane Involved in spindle apparatus orientation

Question 61

Facultative Aerobes

Answer 61

Can switch to aerobic respiration but prefer anaerobic environments

Question 62

Microphiles

Answer 62

Organisms that need oxygen but are poisoned by high concentrations

Question 63

Facultative Psychophiles

Answer 63

Organisms that will survive at temperatures below 20°C but will only grow at temperatures above 20°C.

Question 64

Aerotolerant

Answer 64

Do not require oxygen to survive, but are not poisoned by it (unlike obligate anaerobes)