Chapter 2 Flashcards
3 major cellular components
plasma membrane
nucleus
cytoplasm
cells
basic unit of structure and function
plasma membrane - structure
-phospholipid bilayer
-cholesterol - lot of strength
Proteins
-transmembrane - go all the way through bilayer, act as channels or gateways
- peripheral - on the outside or surface, act as little feelers
plasma membrane - function
separates ICF and ECF
selectively permeable
controls composition of ICF
nucleus
contains cells genetic material
nucleus - structure
- largest organelle
- enclosed by a double layer nuclear envelope with nuclear pores
- contains DNA - organized into chromosomes
DNA
- double helix
- made of sugars, phosphates, and bases
- bases - thymine, adenine, guanine, cytosine
functions of DNA
- directs protein synthesis: making of proteins
- holds genetic blueprint/code during cell replication
RNA
single helix made of bases
mRNA
complimentary copy of DNA that travels out of nucleus
tRNA
gathers the correct amino acids and brings to the ribosome
- taxi - out in the cytoplasm
rRNA
component of ribosomes
protein synthesis
the production of proteins using codes (genes) from DNA
protein synthesis involves transcription and __________
translation
transcription
- the formation of mRNA from DNA via RNA polymerase
- mRNA carries instructions from the nucleus to the cytoplasm (ribosome)
Translation
- of mRNA into a protein
cytoplasm
portion of cell interior not occupied by the nucleus
cytoplasm - structure
- organelles “little organs” - distinct, highly organized, membrane-enclosed structures
- cytosol - complex, gel like mass in which the cytoskeleton is found
organelles:
Endoplasmic Reticulum
- elaborate fluid-filled membranous system distributed throughout the cytosol
- subway (transport) system
Rough Endoplasmic Reticulum
- protein synthesis
- surface has attached ribosomes - protein factories
- a.k.a. granular
Smooth Endoplasmic Reticulum
- lipid synthesis
- no ribosomes
- agranular
- liver SER = detoxifies
Golgi apparatus
- stack of flattened membrane-enclosed sacs called CISTERNAE
- post office
- one side faces rough ER
- packages raw materials into finished products
lysosomes
- membranous sacs containing digestive enzymes
- intracellular digestive cell
- suicide cells
perioxisomes
- house oxidative enzymes that detoxify various waste products
- forms H2O2 -> catalase -> H2O+O2
- creates bubbling effect when peroxide is poured onto a cut
ribosomes
- sites of protein synthesis
- found either attached to rough ER or free in the cytoplasm
- protein factory
mitochondria
- energy organelle
- powerhouse
- contains enzymes for citric acid cycle and ETC
- enclosed by a double membrane
- inner fold membrane = cristae
ATP
- cash of the cell
- cellular energy
- energy storage molecule
- ADP + Pi ATP (making of energy)
ATP generation: Glycolysis
where does it occur
in cytosol (liquid portion)
ATP generation: Krebs
Where does it occur?
in mitochondria
ATP generation: ETC
where does it occur?
in mitochondria (where energy payoff happens)
Glucose
nutrient contains energy
ATP - _______ molecule
energy
H - can be used to make ______
ATP
NAD and FAD carry _______
H ( hydrogen transporters; trucks)
NADH and FADH2 travel to ______
ETC
NADH = ___ ATP
3
FADH2 = ____ ATP
2
glycolysis
chemical process involving 10 separate sequential reactions that break down GLUCOSE into two pyruvic acid molecules
is glycolysis anaerobic or aerobic?
anaerobic
net gain from glycolysis
2 ATP
2 NADH
If no oxygen is present for glycolysis, what happens?
2 NADH are added to pyruvic acid = lactic acid
- muscle pain
- fatigue
- decrease pH
citric acid cycle/Krebs cycle
- pyruvic acid from glycolysis is converted to acetyl CoA which enters CAC = 2 NADH
- consists of 8 separate biochemical responses that are directed by enzymes of mitochondrial matrix
- important in preparing hydrogen carrier molecules for entry into electron transport chain
- requires oxygen
does CAC requires oxygen?
Yes
The CAC is important for preparing ____ carrier molecules for entry into ETC
hydrogen
Payoff from CAC
3 NADH
1 FADH2
1 ATP HAVE TWO CYCLES PER GLUCOSE MOLECULE
ETC
series of reactions that occur on the inner mitochondrial membrane
- major source of ATP
- requires oxygen as the FINAL ELECTRON ACCEPTOR
Oxygen in the __________
final electron acceptor
Does ETC require oxygen?
yes
The ETC produces ATP by ____________
oxidative phosphorylation
Alternate fuel sources - lipids
fatty acids -> enter krebs through beta oxidation
- really concentrated
alternate fuel sources - proteins
amino acids -> enter Krebs through deamination
- dont want to burn them for ATP, can burn them through starvation mode
Aerobic exercise
lots of ATP needed
- with oxygen
- can get to ETC
- long, low intensity
Anaerobic Exercise
- short duration, high intensity (power lifting, sprinting)
the term we use to describe the structure of the cell membrane is ___________
phospholipid bilayer
phosphate heads are arranged so they are in contact with
water
ECF
ICF
this bilayer arrangement allows the cell membrane to be
selectively permeable
phosphate heads are polar molecules. T/F
true
polar means
charge
Things that are soluble in lipids are allowed to move freely through the cell membrane. T/F
true
The control center of the cell is the _______
nucleus
the part of the cell that contains DNA is the ______
nucleus
the largest organelle in the cell is the _____
nucleus
the ______ is surrounded by a double later membrane with pores
nucleus
you just made a complimentary copy of RNA from DNA, this is called _______
transcription
what can RNA do that the original DNA cant do?
travel outside of the nucleus (nuclear pores)
which type of RNA brings the appropriate amino acid to the ribosome?
tRNA
what is the function of RNA polymerase?
produces RNA (binds to DNA and transcribes sequence into RNA)
proteins are long chains of _________
amino acids
name the two parts of the cytoplasm
organelles and cytosol
just by looking at the word “glycolysis” we can figure out what it means……
break down glucose into two pyruvic acid molecules
where does glycolysis occur?
cytosol
glucose is a 6 carbon chain. When we split it we form 2 molecules of pyruvic acid that each contain _____ carbons
3
what is the good news with glycolysis? (what is produced)
2 ATP
2 NADH
what is the bad news of glycolysis? (what do we do with the NADH and pyruvic acid if no oxygen is present?)
2 NADH are added to pyruvic acid = lactic acid
Does the Citric Acid Cycle or ETC produce more ATP?
ETC
before pyruvic acid can enter the CAC, it needs to be modified into a 2 carbon molecule called _____ that joins with the 4 carbon oxaloacetic acid
acetyl CoA
how many turns of the CAC are needed for each glucose molecule
2
How many ATP, FADH2, NADH are produced for each turn?
1 ATP
1 FADH2
3 NADH
that means our total for one molecule of glucose is
ATP = 2 NADH = 6 FADH2 = 2
