Cell Structure and Transport

active transport

adenosine triphosphate (ATP)

diffusion

endocytosis

ion pump

organelle

osmosis

passive transport

plasma membrane

A A partially-permeable phospholipid bilayer with embedded proteins, which forms the boundary of all cells.

B Movement of substances down a concentration gradient without energy expenditure.

C The passive movement of molecules from high to low concentration.

D A transmembrane protein that moves ions across a plasma membrane against their concentration gradient.

E A nucleotide comprising a purine base, a pentose sugar, and three phosphate groups, which acts as the cell's energy carrier.

F The energy-requiring movement of substances across a biological membrane against a concentration gradient.

G Active transport in which molecules are engulfed by the plasma membrane, forming a phagosome or food vacuole within the cell.

H Passive movement of water molecules across a partially permeable membrane down a concentration gradient.

I A structural and functional part of the cell, usually bound within its own membrane.

Examples include the mitochondria and chloroplasts.

2. (a) Identify organelle 1:

(b) The organelle is found in a plant/animal cell/plant and animal cell (delete two).

(c) Identify organelle 2:

(d) The organelle is found in a plant/animal cell/plant and animal cell (delete two).

3. Match the statements in the table below to form a complete paragraph. The left hand column is in the correct order, the right hand column is not.

(a)

(b)

1 2

Cells are the basic...

A cell is enclosed by a plasma membrane... A phospholipid is made up of a... Proteins are embedded...

Eukaryotic cells contain different types of organelle... Each organelle has a specific function in the cell... ...such as photosynthesis or respiration. ...hydrophilic head and a hydrophobic tail. ...units of life.

...in the plasma membrane. ...made of a phospholipid bilayer with embedded proteins ...some of which are composed of membranes.

Transport of molecules though the plasma membrane...

Active transport requires the input of energy... Passive transport involves the movement of molecules from...

Simple diffusion can occur... Facilitated diffusion involves proteins in the plasma membrane...

Active transport involves membrane proteins, which couple the energy provided by ATP... ....to the movement of molecules or ions against their concentration gradient. ...high concentration to low concentration (down a concentration gradient). ...can be active or passive. ...directly across the lipid bilayer of the membrane. ...which help molecules or ions to move through. ...whereas passive transport does not.