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Flashcards in Cell functions Deck (43)
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1
Q

Enzymes

A

Functional proteins. Chemical catalysts reducingactivation energy needed fro a reaction. Regulate metabolic pathways - specific to one substance - inhibited or activated by various physical and chemical agents

2
Q

Cellular respiration review

A

1 glucose (C6H12C6) — glycolysis in cytosol
—>
2 pyruvic acid + oxygen — citric acid cycle and ETC in mitochondrion
—>
CO2 + H2O + 36 or 38 ATP

3
Q

Anabolism

A

Protein synthesis - begins with genetic master code in cell’s DNA - influences all cell structures and functions

4
Q

Cell reproduction

A

Mitosis: Cell reproduce by splitting themselves into two smaller daughter cells - each cell must contain sufficient cytoplasm (including mitochondria and other organelles) as well as complete set of genetic information

5
Q

Allosteric effector

A

Alters enzyme function by changing its shape - may inhibit or activate enzymes by altering shape of active site - includes antibiotic drugs, changes in pH, changes in temperature, and cofactors

6
Q

Glycolysis without oxygen

A

Pyruvate acid molecules will follow the anaerobic pathway to form lactic acid - as oxygen becomes available, lactate converts back to pyruvate or even glucose

7
Q

Glycolysis

A

Glucose break down to form 2 Peruvian acid molecules - occurs in cytosol, outside of any organelle - anaerobic reaction - produces 2 ATP

8
Q

Sodium-potassium pump

A
  • 3 Na+ in cytosol bind to pump proteins, which triggers ATP ydrolysis
  • shape of protein changes and 3 Na+ are deported into ECF
  • 2 K+ then bind, trigger ATP hydrolysis, protein changes shape and 2K+ desposited into cell, protein shape now ready for 3Na+
9
Q

Active transport

A

Requires expenditure of metabolic energy by the cell. Transport by pumps and vesicles. Moves up concentration gradient

10
Q

Exocytosis

A

Processs by which large molecules (proteins) can leave the cell when they are too large to move out throug the cell membrane. Also provides a way to add new plasma membrane

11
Q

Meiosis

A

Cell division that occurs only in primitive sex cells during the process of becoming mature sex cells with 23 chromosomes

12
Q

Isotonic solution

A

Cell stays the same size because there is no net movement of H2O into or out of the cell

13
Q

End product inhibition

A

When a chemical product at the end of a metabolic pathway binds to the allosteric site of one or more enzymes along the pathway that produce it in order to inhibit synthesis of more product (negative feedback)

14
Q

Coenzyme

A

Organic non protein molecule that is a nonprotein cofactors.

15
Q

Diffusion

A

Movement of solute down concentrartion or electrical gradient. Stops when reaches equilibrium

16
Q

Osmosis

A

Movement of water through a semi-permeable membrane down concentration gradient. Particle movement is limited, so water moves. Aquaporins allow movement through phospholipid membranes

17
Q

Passive transport

A

Does not require energy expenditure or activity from membrane. Stuff moves down a concentration or electrical gradient
- diffusion - osmosis - osmotic pressure - channel mediated passive - carrier mediated transport

18
Q

Hypotonic solution

A

Causes the cell to swell as H2O moves into it. Cell may burst (lyse)

19
Q

Carrier mediated transport

A

Facilitated diffusion of solute through a membrane by a carrier. Open on one side, solute enters and binds, it closes and opens the other side. Can be reversible.

20
Q

Transport by pumps

A

Driven by energy from hydrolysis of ATP and energy stored in an ionic concentration gradient - utilizes carrier proteins - most prevelant is sodium-potassium pump.

21
Q

Metabolic pathways

A

Chemical reactions that occur in a sequence of reactions, requires enzymes

22
Q

Hypertonic solution

A

Causes cell to shrink as H2O moves out. Cell may be permanently damaged and die.

23
Q

Receptor-mediated endocytosis

A

Receptors in plasma membrane bind to specific molecules in ECF, which triggers endocytosis

24
Q

Cell metabolism

A

Set of chemical reactions of a cell

25
Q

Phagcytosis

A

Cell engulfs large solid particles (whole bacteria, viruses, worn out cells) and the vesicles fuse with lysosomes that break down unwanted material - undigested materials are secreted by exocytosis or reside within the cell in a residual body

26
Q

Citric acid cycle

A

Pyruvate acid from glucose is converted to acetyl coenzyme A (CoA) - occurs in the mitochondria of the cell (where enzymes are located) - produces CO2 + energy in the form of energized electrons

27
Q

Transport by vesicles

A

Substances dont actually go through the plasma membrane

28
Q

Genetic code

A

Dictates structures of each protein produced by the cell

29
Q

Pinocytosis

A

Cell drinking. ECF enters cell. Cell ingests fluid and solutes and then removes material from plasma membrane (receptors and channels). Cell can regulate membrane this way.

30
Q

Channel mediated transport

A

Facilitated diffusion of solute through a membrane channel. Gated channels open/close by various triggering mechanisms. Protein tunnels. Solute specific.

31
Q

Cell growth

A

Depends on using genetic info in DNA to make the structural and functional proteins needed for cell survival - Newly formed cell synthesize new molecules and organelles, including an extran set of DNA molecules in anticipation of reproduction

32
Q

Active site

A

Chemically fits the substrate on the enzyme. Thats where the magic happens

33
Q

Endocytosis

A

Traps extracellular material and brings it into the cell. Cytoskeleton forms vesicle. 3 types: receptor-mediated endocytosis, phagcytosis, and pinocytosis

34
Q

Equilibrium

A

Equal concentration. Not a static state without movement but a balanced state stat in which the number of molecules crossing the membrane is equal in both directions.

35
Q

Catabolism

A

Protein breakdown

36
Q

Osmotic pressure:

A

Water pressure that results from osmosis. Osmotic pressure is higher in the solution with higher concentration and this drives the water out.

37
Q

Catalysts

A

Participate in chemical reactions but are not themselves changed by a reaction

38
Q

Cellular respiration

A

Glucose —> CO2 + H2O + energy

Glycolysis + citric acid cycle + electron transport chain

39
Q

Electron transport chain

A

Energized e- are carried to specialized molecules embedded in the inner mitochondrial membrane - e- are shuttled along a chain of specialized molecules and cause protons to be pumped into intermembrane space - protons (H+) cross back through the inner mitochndrial membrane into inner chamber by way of reverse pump carriers - ATP synthase carriers convert the energy of passive proton flow into chemical energy which is transferred to ATP molecules - produces 34 ATP (along with citric acid cycle)

40
Q

Glycolysis with oxygen

A

Pyruvate acid molecules will follow the aerobic pathway and enter the citric acid cycle

41
Q

Kinases

A

Active enzymes, which are naturally inactive because they are synthesized as inactive proenzymes

42
Q

Transcription

A

Gene code in DNA is copied to messenger RNA (mRNA) in the cell nuclus - mRNA separates from the DNA strand and carries a “message” of gene code sequence to a ribosome in the cytoplasm - cell translates genetic code - tRNA transfers amino acids from cytoplasm to the ribosome - as amino acids are brought into place, peptide bonds join them to produce an entire protein (process of translation)

43
Q

Dynamic equilibrium

A

Condition of continual, constant diffusion