section 1: cell structure - topic 1: cells & organelles Flashcards
what are the 2 types of organism?
prokaryotes.
eukaryotes.
what organelles are found in an animal cell?
cell surface membrane.
RER.
nucleus.
nucleolus.
SER.
lysosome.
ribosome.
nuclear envelope.
golgi apparatus.
cytoplasm.
mitochondrion.
what organelles are found in a plant cell?
cell surface membrane.
RER.
nucleus.
nucleolus.
SER.
lysosome.
ribosome.
nuclear envelope.
golgi apparatus.
cytoplasm.
mitochondrion.
cell wall with plasmodesmata (‘channels’ for exchanging substances between adjacent cells).
vacuole (compartment that contains cell sap).
chloroplasts (organelles involved in photosynthesis)
what is the cell surface membrane?
the membrane found on the surface of animal cells & just inside the cell wall of plant cells & prokaryotic cells.
mainly made of lipids and proteins.
what is the function of the cell surface membrane?
regulates the movement of substances into and out of the cell.
has receptor molecules on it, which allow it to respond to chemicals like hormones.
what is the cell wall?
a rigid structure that surrounds plant cells.
mainly made of cellulose (carbohydrate).
what is the function of the cell wall?
supports plant cells.
what is the nucleus?
a large organelle surrounded by a nuclear envelope (double membrane) which contains many pores.
the nucleus contains chromatin (which is made from DNA & protein) & often a structure called the nucleolus.
what is the function of the nucleus?
controls the cells activities (by controlling the transcription of DNA).
DNA contains instructions to make proteins.
the pores allow substances (i.e. RNA) to move between the nucleus & the cytoplasm.
the nucleolus makes ribosomes.
what is a lysosome?
a round organelle surrounded by a membrane with no clear internal structure.
what is the function of a lysosome?
contains digestive enzymes - these are kept separate from the cytoplasm by the surrounding membrane, and can be used to digest invading cells or to break down worn out components of the cell.
what is a ribosome?
a very small organelle that either floats free in the cytoplasm or is attached to the rough endoplasmic reticulum.
made up of proteins & RNA.
not surrounded by a membrane.
what is the function of a ribosome?
the site where proteins are made.
what is the RER?
a system of membranes enclosing a fluid-filled space.
surface is covered with ribosomes.
what is the function of the RER?
folds & processes proteins that have been made at the ribosomes.