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1

Key factor limiting maximal cell size

Surface area to vol ratio

2

Differences betweeen prokaryotic and eukaryotic cell

prokaryotic cells do not have membrane-enclosed organelles

3

common feature between prokaryotic and eukaryotic cell

plasma membrane, DNA, ribosomes

4

Why does rough ER appear 'rough'

presence of ribosomes on ER membrane surface

5

What is stored in animal nucleus

Chromosomal DNA

6

Order of compartments in endomembrane system

ER → golgi →lysosome

7

Organelle where lipids are synthesised

smooth ER

8

Golgi functions

- sort and distribute cargo derived from the ER
- both absorb/merge with and release transport vesicles
- process sugars added to proteins and lipids added in the ER

9

Vesicles leaving transface of Golgi may go to:

the plasma membrane, vacuoles, lysosomes

10

function of nucleolus

site of ribosome synthesis and assembly

11

Shape of inner membrane of mitochondria

inc. surface area to volume ratio →more energy

12

A cells plasma membrane

- is selectively permeable
- flexible
- fluidity

13

define - Selectively permeable

allows some molecules through by passive or active transport

14

phospholipid

polar head group and non polar fatty acid rail

15

increasing level on unsaturated fatty acids in phospholipids

- increase membrane fluidity
- decrease viscosity

16

Organism membranes at colder temps

more phospholipids with unsaturated fatty acid tails

17

Facilitated diffusion does not require

energy expenditure

18

What molecules are most likely to diffuse through a cells plasma membrane

Small non-polar

19

Active transport

- can move molecules against their concentration gradient
- requires energy to be expended

20

osmosis

when water molecules move from high to low concentration across a plasma membrane

21

Hypertonic

solute concentration outside a cell is higher than inside.

22

exocytosis

Form of active transport where eukaryotic cells transport proteins out of the cell

23

phagocytosis

form of active transport which amoeba ingests a bacterial cell such as paramecium

24

forms of potential energy

- chemical bond energy
- ion gradient across a membrane
- ATP

25

1st law of thermodynamics

energy is never created or destroyed but can change forms

26

exergonic

reactions that are spontaneous in living systems

27

spontaneous reactions may not by instantaneous

bc even exergonic reactions may require activation energy

28

activation energy

initial energy needed to start a chemical reaction

29

enzymes

- biological catalysts
- specific for their substrates
- are proteins

30

competitive inhibitors of biochemical reactions bind to an enzymes

active site