Cells and their functions Flashcards
functions of nucleus?
contains genetic information (DNA OR RNA) and controls cell activities
characteristic of plasma membrane? (3 points)
allows only some substances to pass through it (controls movement of substances in and out the cell)
surrounds the cytoplasm of the cell
separates the cell from external environment
functions of cell wall? (2 points)
protect cell from injury
gives it fixed shape
functions of cytoplasm
contains organelles, jelly like (where most cell activities occur)
describe rough endoplasmic reticulum 2 (points)
flattened spaces lined with a membrane
outer surface of RER is continuous with the nucleus membrane
why is the RER rough?
small particles, ribosomes, are attached to its outer surface
where can ribosomes be found?
attached to the RER or lie freely in the cytoplasm
functions of ribosomes in RER?
Transport proteins made by the ribosomes to the Golgi Body (for secretion out the cell)
functions of ribosomes lying freely in the cytoplasm?
make proteins that are used within the cytoplasm of the cell
functions of smooth endoplasmic reticulum?
(2 points)
synthesises substances such as fats and steroids
purify harmful substances into harmless substances through detoxification
functions of golgi body? (2 points)
chemically modifies substances made by the endoplasmic reticulum
stores and packages substances in vesicles for secretion out the cell
what takes place in mitochondria?
aerobic respiration occurs in the mitochondria.
functions of aerobic respiration?
food substances are broken down to produce Adenosine Triphosphate (ATP) —> for cell’s growth and reproduction (cell division)
more folds in the mitochondria…
more fold, more surface area, increase rate of aerobic respiration and the production of ATP
characteristic of chloroplast? (plant cell)
contains chlorophyll for photosynthesis
vacuoles contains…. and is surrounded…
contains substances (sugar, mineral, amino acids for plant cell and water, food substances for animal cell)
surrounded by a single membrane known as tonoplast which is partially permeable
define selectively permeable membrane
it allows SOME substances to pass through it (allows substances that the cell need –> not size based)
define partially permeable membrane
It allows substances THAT IS ABLE TO pass through it MORE EASILY than other (size based)
list the level of organisation
cells –> …….
cells —> tissues —> organs —> organ systems (e.g. digestive system) —> organism (chicken, pig etc)
functions of the chromatin
made of DNA and proteins
during cell division, will split up and form CHROMOSOMES that will CONDENSE into tightly coil structures
list three double bound membrane
nucleus, mitochondria, chloroplast
