B1: Cells Flashcards
(47 cards)
cell membrane euk
structure + description
A partially permeable layer that forms a boundary around the cytoplasm of the cell.
cell membrane euk
function
Contains the cell contents and controls the movement of some substances into and out of the cell.
It allows H20, 02 and nutrients to enter and allows waste products (e.g. carbon dioxide) to leave.
chromosomal DNA euk
structure + description
One or more
linear pieces of
double-stranded DNA
chromosomal DNA euk
function
Stores the genetic material
required for the various cell processes.
cytoplasm euk
structure+ description
A jelly-like region, surrounded by the cell membrane.
Salt ions and sugar molecules are dissolved in it.
Fat molecules and proteins, e.g. enzymes, are suspended in it.
Also contains food reserves (e.g. glycogen in some animal cells, starch in some plant cells) and organelles such as the nucleus and mitochondria.
Chloroplasts are present in the cytoplasm of photosynthetic plant cells
cytoplasm euk
function
Is the site of chemical reactions
contains enzymes that control these reactions.
`It holds the cell organelles.
nucleus
structure+ description
Usually round or oval,
contained by two nuclear membranes and containing DNA in the form of chromosomes.
It is found inside the cytoplasm.
nucleus
function
Regulation of cell functions through directing the production of RNA and protein required for all cell processes,
including cell division, cell differentiation (specialisation) and cell metabolism (chemical reactions).
mitochondrion
structure + description
A small organelle
(can be viewed using an electron microscope)
with an inner and outer membrane.
The inner membrane has many inward-pointing folds.
mitochondrion
function
Controls the production and release of ATP
(usable energy)
from aerobic respiration.
cell wall euk
structure +description
A tough, rigid layer
surrounding the cell membrane
made primarily of cellulose.
It is freely permeable to water and salts.
cell wall euk
function
Provides a rigid external coat to plant cells,
providing mechanical strength which allows cells to resist bursting when the cell is turgid.
chloroplast
structure+ description
A small organelle
with its own double membrane,
found in the cytoplasm of photosynthetic plants,
containing chlorophyll and other pigments.
chloroplast
function
Traps (absorbs) light energy
converts it to chemical energy
by the process of photosynthesis.
vacuole
structure + function
A fluid-filled space surrounded by a membrane in plant cells.
It is found inside the cytoplasm.
The fluid is called sap- watery solution of sugars and salts, can be coloured.
vacuole
function
Stores water-soluble chemicals and ions
helps to keep plant cells and tissues firm.
cell membrane prok
structure+ description
A partially permeable layer
that forms a boundary between the cytoplasm and the cell wall.
Functions as a boundary to restrict materials moving between the inside and outside of a cell.
cell membrane prok
function
Contains the cell contents and controls the movement of some molecules into and out of the cell.
cytoplasm prok
structure + description
Is the site of chemical reactions
contains enzymes that control these reactions.
It holds the cell’s DNA.
cell wall prok
structure + description
A tough, rigid external coat that surrounds the cell membrane.
It is made of a complex mixture of proteins, lipids (fats) and sugars.
This makes it different from plant cell walls, which are made of cellulose.
Some bacterial cells have a slime capsule surrounding the cell wall.
cell wall prok
function
Provides structural support and protection to bacteria. freely permeable to small molecules, so does not control the intake or loss of materials.
chromosomal DNA bacteria
structure + descriptio
A large closed circular coiled molecule of double-stranded strand DNA
located within the bacterial cytoplasm (no nucleus or enclosing membrane).
chromsomal DNA bacteria
function
Carries genetic information that regulates most bacterial cell processes.
Plasmid DNA
structure + descriptipn
A small molecule of closed double-stranded circular DNA,
usually present in multiple copies per cell.
