Biology Unit 2 Flashcards
(79 cards)
1
Q
Cell Theory
A
- All organisms have 1+ cells
- Cells come from division of preexisting cells
- Cells pass heredity material to offspring
- Cell is structural and functional unit of all organisms
2
Q
ALL cells have…
A
Plasma membrane
Cytoplasm
DNA
3
Q
Plasma membrane
A
- Outermost membrane of a cell
- Encloses a jellylike mixture called cytoplasm
- Suspended in the cytoplasm are specialized organelles
4
Q
All cells start out life with DNA
A
In eukaryotic cells, DNA is contained within the nucleus
5
Q
Lipid bilayer
A
Composition of nearly all cell membranes that’s a double layered sheet
6
Q
Cell membrane
A
Regulates what enters and leaves the cells and provides protection and support
7
Q
Cell
A
- Every living cell exists in a liquid environment
- Cells=10-20 micrometers in diameter
- Cell size is limited by surface-to-volume ratio
- Volume increases with the cube of the diameter
- Surface area increases with the square
- When cell expands in diameter, it’s volume increases faster then it’s surface area
8
Q
Soltion
A
Mixture of two or more substances
9
Q
Solutes
A
Dissolved in solution
10
Q
Solvent
A
The dissolvent
11
Q
Concentration
A
The mass of solute in a given volume of solution, or mass/volume
12
Q
Diffusion
A
- Particles in a solution tend to move from an area where they are more concentrated to an area where they are less concentrated
- Spontaneous spreading of molecules or ions
- Essential for substances to move into, through, and out of cells
13
Q
Equilibrium
A
The concentration of the solute is the same throughout a system
14
Q
Fluid mosaic
A
Model of a cell membrane as a 2-dimensional fluid of mixed composition
15
Q
Types of proteins
A
Adhesion, recognition, receptor, & transport
16
Q
Adhesion proteins
A
Helps cells stick together
17
Q
Recognition proteins
A
Identifies “self” cells
18
Q
Receptor proteins
A
Triggers a change in cell activity
19
Q
Transport proteins
A
Assists the movement of ions or molecules across the membrane
20
Q
Nucleus
A
Protects DNA from the metabolic process of the cell
21
Q
Nuclear envelope
A
Outer boundary of the nucleus; controls access to DNA
22
Q
Nucleoplasm
A
Viscous fluid enclosed by the nuclear envelope
23
Q
Nucleuolus
A
Dense, irregularly shaped region where ribosomal subunits are assembled
24
Q
Nuclear pore
A
Pores in our envelope responsible for mRNA
25
Endomembrane system
- Series of interacting organelles between nucleus and plasma membrane
- Endoplasmic reticulum, Golgi bodies, vesicles
- Produces lipids and proteins
26
Vesicles
- Small, membrane enclosed organelle
- Transports substances
- Collects and disposes of waste, debris, or toxins
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Peroxisome
Breaks down amino acids, fatty acids, and toxic substances
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Lysosomes
Breaks down cellular wastes and debris
29
Vacuoles
Fluid filled; isolates or disposes of waste, debris, or toxic materials
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Central Vacuole
Fluid filled vesicle in many plant cells
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Endoplasmic Reticulum
A continuous system of sacs and tubes extending from the nuclear envelope
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Smooth ER
Makes lipids and breaks down carbohydrates and fatty acids
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Rough ER
Ribosomes on the surface synthesize proteins
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Golgi body
- Modifies proteins
- Packages the finished products into vesicles
- Some of the vesicles deliver their cargo to the plasma membrane; others become lysosomes
35
Mitochondria
- Double-membrane organelle that produces ATP by aerobic respiration in eukaryotes
- Nearly all eukaryotic cells have mitochondria (including plant cells)
36
Plastids
Double-membranes organelles that function in photosynthesis, storage, or pigmentation in plant and algal cells
37
Chloroplasts
Specialized plastid for photosynthesis in some protists and plant cells
38
What affects the rate of diffusion?
Size, temperature, concentration, charge, and pressure
39
Lipid bilayers are selectively permeable
-Water can cross, but ions and polar molecules cannot
40
Juror pressure/Jurgor?
- Stiff cell walls keep plant cells from expanding very much
| - Inflow of water causes pressure to build up
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Turgor
Pressure that a fluid exerts against a structure
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Osmotic pressure
Amount of Turgor that prevents osmosis into cytoplasm or other hypertonic fluid
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Transport proteins
Allow only specific substances to cross the cell membrane
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Passive transport
Solutes move through membrane; requires no energy
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Active transport
Transport protein pumps a solute against its concentration gradient; requires energy
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Active transport: Vesicle movement
Exocytosis, endocytosiss, phagocytosis
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Exocytosis
Cell expels a vesicles contents to extracellular fluid
48
Endocytosis
Cell takes in a small amount of extracellular fluid by the ballooning inward of the plasma membrane
49
Phagocytosis
"Cell eating" and endocytic pathway by which a cell engulfs particles such as microbes or cellular debris
50
Membrane proteins and lipids are made:
In the ER and move to the Golgi bodies for final modification
51
Exocytosis and endocytosis
Continually replace and withdraw membrane patches
52
In order to use the energy stored in sugars, cells must 1st...
Transfer the sugar to ATP
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Energy transfer occurs when...
The bonds of a sugars carbon backbone are broken, driving ATP synthesis
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2 main mechanisms break down sugars to make ATP:
Aerobic Respiration and Fermentation
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Aerobic Resperation
- Requires oxygen to break down sugars to make ATP
- Releasing pathway in nearly all eukaryotes and some bacteria
- Occurs in the mitochondria of a cell
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3 stages of aerobic relegation produce 36 ATP:
Glycolysis, Krebs, ETP
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Glycolysis
- Occurs in the cytoplasm; net yield is 2 ATP
| - Taking a sugar and breaking it in half
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Krebs cycle
Occurs in the mitochondria; net yield is 2 ATP
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ETP/Electron transfer phosphorylation
Occurs in the mitochondria; net yield is 32 ATP
60
Fermentation
- Sugar breakdown pathway that does not require oxygen to make ATP
- Begins with glycolysis in the cytoplasm
- Occurs entirely in the cytoplasm and does not include electron transfer chains
- Net yield is 2 ATP, which provides enough ATP to sustain many single-celled species
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Cellular respiration and mitochondria
- Cells require a constant source of energy for life process
| - Respiration occurs in ALL cells and can take place either with or without oxygen
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Aerobic respiration formula:
C6⃣H1⃣2⃣O6⃣+6O2⃣ to 6CO2⃣+6H2⃣O+36ATP
| Glucose+Oxygen to Carbon Dioxide+Water+Energy
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Explain Krebs cycle
Explain Krebs cycle
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Explain electron transport chain
Explain electron transport chain
65
Energy
Energy for living things come from food, originally, they come from the sun
66
Autotrophs
Organism that use LIGHT ENERGY from the sun to produce food
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Heterotrophs
Organisms that CANNOT use the Suns every to make food
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Cell energy
- Cells usable source of energy called ATP
- All energy is stored in the bonds of compounds, breaking the bond, releases the energy
- When a cell has energy available, it can store this energy by adding a phosphate group to ADP, producing ATP
- ATP is converted into ADP by breaking the bond between the 2nd and 3rd phosphate groups and releasing energy for cellular process
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ATP stands for...
Adenosine Triphosphate
70
Photosynthesis
- The energy of sunlight is converted into the energy of glucose
- Occurs in chloroplasts of plants
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Pigment
- Light absorbing compound
| - Absorb some wavelengths of light and reflect others(the color our eyes see is the color that the pigment reflects)
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Chlorophyll
The pigment inside the chloroplast that absorbs light for photosynthesis
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Photosynthesis formula
6CO2⃣+6H2⃣O+light to C6⃣H1⃣2⃣O6⃣+6O2⃣
| Carbon dioxide+water+light to glucose+oxygen
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Light dependent reaction
H2⃣O is broken down and light energy is stored temporarily in inorganic energy carries, ATP and NADPH
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Calvin Cycle
Energy is transferred from ATP and NADPH to the organic compound glucose
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Osmosis
Diffusion of water across a permeable membrane
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Hypotonic
A fluid that has a low solute concentration
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Hypertonic
A fluid that has a high concentration
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Isotonic
2 fluids with identical solute concentrations
