Biology Flashcards
Eukaryotic DNA?
Eukaryotes are organisms made up of a cell or cells containing DNA inside a recognisable nucleus. The DNA is present in the form of one or more linear chromosomes within the nucleus.
Plant cells tend to be ? than animal cells?
Plant cells tend to be larger than animal cells.
All eukaryotic cells have?
a cell membrane and cytoplasm, most have nucleus
mitochondria are not visible using a ?
light microscope
Most eukaryotic cells have ?
a nucleus. Exceptions are mature red blood cells in mammals.
plant cells have?
- cytoplasm
- cell wall
- sap vacuole
- cell membrane
- nucleus
- photosynthetic ones have chloroplasts
CM structure and description?
A partially permeable layer that forms a boundary around the cytoplasm of the cell
Chromosomal DNA structure + description?
One or more linear pieces of double-stranded DNA.
cytoplasm 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.
- 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.
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.
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.
plant only components are?
- cell wall
- chloroplast
- vacuole
structure +description cell wall?
A tough, rigid layer surrounding the cell membrane made primarily of cellulose. It is freely permeable to water and salts.
chloroplast structure + description?
A small organelle with its own double membrane, found in the cytoplasm of photosynthetic plants, containing chlorophyll and other pigments
vacuole structure + description?
A fluid-filled space surrounded by a membrane in plant cells. It is found inside the cytoplasm. The fluid is called sap, which is a watery solution of sugars and salts. In some cells, e.g. rhubarb, it is also coloured.
CM function?
- Contains the cell contents - - controls the movement of some substances into and out of the cell.
- It allows water, oxygen and nutrients to enter and allows waste products (e.g. carbon dioxide) to leave.
Chromosomal DNA function?
Stores the genetic material required for the various cell processes.
Cytoplasm function?
Is the site of chemical reactions and contains enzymes that control these reactions. It holds the cell organelles.
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 function?
Controls the production and release of ATP (usable energy) from aerobic respiration.
Cell wall function?
Provides a rigid external coat to plant cells, providing mechanical strength which allows cells to resist bursting when the cell is turgid.
Chloroplast function?
Traps (absorbs) light energy and converts it to chemical energy by the process of photosynthesis.