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Flashcards in 5. Cell Organisation Deck (26):
1

Amphipathic

Molecules with both hydrophilic and hydrophobic regions

2

Fluidity of phospholipids

Depend on length of the tail: 1. the longer, the tighter the less degree of saturation 2. double bonds (unsaturated) reduce tightness of packing > more fluid

3

Cholesterol effect on fluidity

standard cell temps: cholesterol decreases membrane fluidity --> ring structure interaction with fatty acid tails reduces mobility
low temps: increases membrane fluidity --> prevents tight packing of phospholipids

4

Functions of proteins (5)

Antibody; Enzyme; Messenger; Structural; Transport/Storage

5

Transmembrane proteins

Span entire lipid bilayer

6

Integral membrane proteins

permanently associated with cell membranes, cannot be separated

7

Peripheral membrane proteins

Temporarily associated with lipid bilayer, easily separated

8

Fluid Mosaic Model

Lipid bilayer is a fluid structure within which molecules move laterally

9

Prokaryotic vs Eukaryotic Cells

Prokaryotic cells do not have nuclei

10

Endoplasmic Reticulum

Organelle in which proteins and lipids are synthesized

11

Golgi apparatus

Modifies proteins and lipids from Endoplasmic Reticulum and acts as a sorting station

12

Lysosomes

Contain enzymes that break down macromolecules

13

Peroxisomes

Involved in important metabolic reactions

14

Mitochondria

Harnesses energy for the cell

15

Cytoskeleton

the protein scaffold

16

Cytoplasm

entire contents of a cell other than the nucleus

17

Cytosol

jelly-like internal environment

18

What do plant cells have but not animal cells?

Cell wall
Vacuoles
Chloroplasts

19

Homeostasis

the active maintenance of a constant environment

20

Permeability of ions, polar molecules and non polar molecules (most to least)

non-polar molecules --> small polar molecules --> large polar molecules --> ions

21

Passive Transport

(facilitated) Diffusion

22

Primary Active Transport

Movement of molecules against conc. gradient
Uses ATP

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Secondary Active Transport

Movement of molecules against conc. gradient driven by movement of protons down conc. gradient
Uses potential energy of electrochemical gradient

24

Hypertonic

the ion concentration in the cell/system is MORE THAN that of the system/cell

25

Isotonic

Equal ion concentration

26

Hypotonic

the ion concentration in the cell/system is LESS THAN that of the system/cell