Term 1 Flashcards
(89 cards)
1
Q
biological science
A
observation, identification, experimental investigation and theoretical explanation of natural phenomena
2
Q
the cell theory
A
- all living things are composed of cells and substances produced by cells or developed out of cells
- basic functional units of organisms
- must be in a constant environment to efficiently obtain nutrients and excrete wastes
- all cells come from pre existing cells
- all cells contain genetic material which is passed on to daughter cells
3
Q
labelled microscope
A
check book
4
Q
total magnification formula
A
eye piece magnification x objective lens magnification
5
Q
field of view
A
the area you see > the diameter of the area you will see with no objective lens
6
Q
10x/22?
A
10 = eye piece magnification 22 = field number
7
Q
how many micrometres in a millimetre
A
1000
8
Q
millimetres
A
10^-3
9
Q
micrometres
A
10^6
10
Q
field of view under high power formula
A
diameter (HP) = [diameter (LP) x magnification (LP)]/ magnification (HP)
11
Q
the higher the magnification, the ___ (higher/lower) the field of view
A
lower
12
Q
cell membrane
A
- selectively permeable barrier that controls movement in and out of the cell
- 7.5 nm in width
- bilipid (two sheets of polar phospholipids)
13
Q
some substances pass through easier than others because they are ____ (larger/smaller)
A
smaller
14
Q
the cell membrane has phospholipids with hydro___ heads and hydro___ tails
A
philic
phobic
15
Q
diffusion
A
- passive transport
- the process by which substances move from an area of high concentration to low, down the concentration gradient (the difference in the concentrations)
- no energy used
16
Q
equilibrium (diffusion)
A
when substances are equally distributed
17
Q
simple diffusion
A
free and unaided movement of molecules through the cell membrane down their concentration gradient
18
Q
facilitated diffusion
A
globular proteins move molecules through the cell membrane down their concentration gradient
19
Q
osmosis
A
the diffusion of water across a semi-permeable membrane down its concentration gradient
20
Q
active transport
A
cellular energy is used to move molecules against their concentration gradient
21
Q
exocytosis
A
active transport out of the cell
22
Q
endocytosis
A
active transport into the cell
23
Q
two types of endocytosis
A
phagocytosis and pinocytosis
24
Q
phagocytosis
A
takes in larger substances (e.g. bacteria)
25
pinocytosis
takes in fluids and solute
26
surface area
the area of outer surface on an object
27
volume
3D space inside an object
28
as an object gets larger, SA:V gets ____ (larger/smaller)
smaller
29
the bigger the cell, the ____ (bigger/smaller) the volume and the ____ (more/less) nutrients needed and wastes produced
bigger
| more
30
a ____ (larger/smaller) SA:V ratio is more desirable (and why)
larger
| - allow enough nutrients and wastes through the membrane and keep it functioning efficiently
31
when a cell grows, its volume increases at a ____ (greater/less) rate than its surface area and so the SA:V ____ (decreases/increases)
greater
| decreases
32
cells
- basic building blocks of all living things
- provide structure for the body
- take in nutrients and convert them into energy
- carry out specialized functions
33
prokaryotes
unicellular organisms (microorganisms)
34
e.g. of prokaryotic cells
amoeba, unicellular fungi, bacteria, protozoa, unicellular yeasts, unicellular algae, paramecium
35
eukaryotes
multicellular organisms
| - all organisms are made of 2 or more cells and they need all parts to survive
36
levels of organisation
cells > tissues > organs > organ systems > organisms
37
features of a prokaryotic cell
- pre nucleus
- most primitive cells- smallest and simplest
- neither nucleus nor membrane bound organelles (but has a cell membrane)
- single cell with DNA
- lacks a nucleus and organelles
- smaller (0.5-2um)
- the only organisms for 2 billion years)
- have a cell wall covered by a capsule
- frail cytoskeleton that aides movement
- some have a flagella and pilus
- only organelle is ribosomes in cytoplasm
- unicellular
38
features of a eukaryotic cell
- true nucleus
- first cells to appear on Earth with internal compartments (organelles)
- nucleus surrounded by cytosol (cytoplasm)
- complex cytoskeleton
- larger (10um) and more complex
- contains nucleus and membrane-bound organelles
39
organelles
- minute subcellular structures with particular functions
| - organs of cells
40
e.g. of eukaryotic cells
animals cells, plant cells, and some protists
41
cell wall
- protects the cell and gives it shape
- made of cellulose
- found in plants, algae, fungi, and most bacteria
42
cell membrane
- outer covering, protective layer around all cells
- for cells with cell walls, the membrane is inside
- allows food, oxygen and water into the cell and waste products out of the cell
43
cytoplasm
- gelatin-like inside cell membrane that constantly flows
| - aka protoplasm
44
chloroplasts
- convert light energy of the Sun into sugars to be used by cells
- photosynthesis depends on the chlorophyll (green pigment) molecules in the chloroplasts
- two membranes
45
vacuoles
temporary storage spaces for food, water and waste
46
nucleus
- directs all cell activities and contains instructions for everything the cell does
- these instructions are found on DNA (hereditary material)
- usually the largest organelle
47
mitochondria
- double membrane celled organelles that release energy from food by breaking down food into carbon dioxide
- metabolize or breakdown carbohydrates and fatty acids to generate energy
- eukaryotic cells use energy in the form of a chemical molecule called ATP (adenosine triphosphate)
- the powerhouse because they release energy from food
- double membrane celled organelle
- synthesize proteins for their own use
- inner membrane is folded to form a series of cristae (shelves) which increases the SA of the membrane
- spherical - high SA:V ratio for the efficient uptake and release of materials
48
endoplasmic reticulum
- series of folded membranes that move proteins around in a cell
- like a conveyor belt
- two types - smooth and rough
- flattened membrane bound sacs called cisternae
49
smooth ER
- responsible for the synthesis and transport of lipids and steroids
- ribosomes not attached
50
rough ER
- ribosomes attached
| - responsible for the synthesis of proteins
51
golgi bodies
- stacked flattened membranes
| - sort and package proteins
52
lysosomes
- the purpose is to digest things - food or breaking down the cell when it dies
- break down food molecules, cell wastes, and worn out cell parts
53
nucleolus
makes ribosomes > make proteins
54
which organelle contains its own DNA?
nucleus
55
what is the relationship between the ER and golgi apparatus?
the golgi sorts and packages proteins and the ER moves them
56
what structures are found in plants but not animal cells
cell wall, central vacuole, chloroplasts
57
enzyme
- produced in living cells
| - catalysts that speed up reactions in organisms
58
active site
- portion of an enzyme in contact with substrate
59
substrate
- a substance that attaches to enzyme active site
60
catalyst
a chemical that causes a chemical change (but isn't altered by the reaction) and speeds up the reaction
61
lock and key model
- at active sites, enzyme has specific geometric shape and orientation that a complementary substrate fits into perfectly
62
induced fit model
when an enzyme binds to appropriate substrate, subtle changes in the active site occur- enhances catalysis as the enzyme converts substrate to product
63
photosynthesis
the method by which most autotrophs make their food i.e. obtain energy and store it as chemical energy
the process whereby radiant energy from the Sun is converted to the chemical bond energy of glucose
64
photosynthesis formula (word form)
carbon dioxide + water > glucose + oxygen
| arrow = sunlight + chlorophyll
65
photosynthesis formula
6CO2 + 6H20 > C6H12O6 + 6O2
66
stoma
open space inside a chloroplast
67
thylakoid
contains green chlorophyll, that absorbs light
68
grana
stacks of thylakoid
69
two types of photosynthesis reactions
light and dark
70
photosynthesis process
- light hits chlorophyll and an electron from the molecule gets excited
- chloroplast holds chlorophyll in a protein complex called the reaction centre, allows the electron to be ejected and used to drive photosynthesis
71
factors affecting photosynthesis
- light
- temperature
- CO2
- chlorophyll
- H2O
72
when a process depends on more than one factor...
the rate of that process is limited by the factor that is in the shortest supply
73
as the intensity of the light or carbon dioxide increases (individually), the rate of photosynthesis ___ (increases/decreases), until _ ___ __ ____. At this point it is further limited by other factors.
increases
| it reaches its limit
74
as the temperature increases, the rate of photosynthesis ____ (increases/decreases), until the _____. From that point, when temperature increases, rate ____ (increases/decreases), until it eventually ___.
increases
maximum
decreases
stops
75
what happens during a light reaction
ADP + light energy > ATP
| H2O > H + O2
76
what happens during a dark reaction
CO2 + H > sugars
| ATP > ADP + energy
77
in which part of the cell does glycolysis occur?
cytoplasm
78
in which part of the cell does Kreb's cycle occur?
mitochondria
79
in which part of the cell does electron transport chain occur?
mitochondria
80
how many molecules of ATP are produced during glycolysis?
2
81
the absence or presence of which substance determines what pathway the molecule pyruvate proceeds down?
oxygen
82
aerobic respiration
efficient production of energy, requiring oxygen to occur
- involves Kreb's Cycle and ETC
- produces large amounts of ATP (34-36) from each glucose molecule
- mitochondria
- products = waste products and water
83
anaerobic respiration
not as efficient method of producing small amounts of energy, without the involvement of oxygen
- involves glycolysis (splitting of glucose)
- occurs in cytoplasm
- for each molecule of glucose, 2 ATP are produced rapidly
- followed by fermentation into either lactic acid or ethanol
- used only if there is not enough O2 for aerobic respiration
- can be useful for rapid rate of release of energy
84
waste products produced during cellular respiration
lactic acid, ethanol, CO2, H2O
85
overview of cellular respiration
1. a glucose molecule enters cell
2. glycolysis > produces 2 molecules of ATP and 2 of CO2
3. forms pyruvate - different paths based on presence of oxygen
```
anaerobic: pyruvate undergoes process of fermentation
forms ethanol (in plants and fungi)
forms lactic (in animals) ENDS HERE
```
aerobic: pyruvate is converted to Acetyl CoA
86
overview of cellular respiration
1. a glucose molecule enters cell
2. glycolysis > produces 2 molecules of ATP and 2 of CO2
3. forms pyruvate - different paths based on presence of oxygen
```
anaerobic: pyruvate undergoes process of fermentation
forms ethanol (in plants and fungi)
forms lactic (in animals) ENDS HERE
```
aerobic: pyruvate is converted to Acetyl CoA
4. Kreb's Cycle > produces 2 molecules of ATP and 4 of CO2
5. Electron Transport Chain > produces 32-34 molecules of ATP
6. H2O + waste products
87
overview of cellular respiration
1. a glucose molecule enters cell
(in cytoplasm)
2. glycolysis > produces 2 molecules of ATP and 2 of CO2
3. forms pyruvate - different paths based on presence of oxygen
```
anaerobic: pyruvate undergoes process of fermentation
forms ethanol (in plants and fungi)
forms lactic (in animals) ENDS HERE
```
(in mitochondria)
aerobic: pyruvate is converted to Acetyl CoA
4. Kreb's Cycle > produces 2 molecules of ATP and 4 of CO2
5. Electron Transport Chain > produces 32-34 molecules of ATP
(out)
6. H2O + waste products
88
cellular respiration
process of turning glucose into energy rich ATP molecules, that occur at any set time
89
cellular respiration
1. glycolysis
2. kreb's cycle
3. electron chain transport
