Cell structures Flashcards
spell out in your head the 2 basic types of cells
prokaryotic cells and eukaryotic cells
what is an example of a prokaryotic cell?
bacteria
what are eukaryotic cells?
plants, animals, fungi and protoctista
important features of prokaryotic cells
- small and unicellular
- has a peptidoglycan cell wall
- does not have membrane-bound organelles
- nucleoid contains DNA
- does not have a nucleus
what are the structures present in prokaryotic cells?
important 1. peptidoglycan cell wall 2. cell surface membrane 3. nucleoid 4. ribosomes 5. cytoplasm unimportant 5. pili (pilus for singular) 6. flagella (flagellum for singular) 7. food granule 8. plasmid 9. mesosome
differences between plant and animal cells
A plant cell has a cellulose cell wall but an animal cell does not.
A plant cell has a large permanent vacuole but an animal cell has small temporary vacuoles.
A plant cell has chloroplast but an animal cell does not.
similarities between plant and animal cells
both of them have cell surface membrane, golgi apparatus, mitochondrion, ribosomes, smooth and rough endoplasmic reticulums, nucleus, nucleolus, nuclear envelope
what is the role of a cell surface membrane?
it is an extremely thin structure that consists of lipid bilayer in which proteins are embedded.
can form vesicles.
functions:
retains cytosol
forms a barrier across which all substances entering and leaving the cell must pass.
what is the role of a nucleus?
largest organelle
it contains chromosomes that are made up of DNA and protein.
function:
involved in cell management and its behaviour when cell divides
what is the role of a nuclear envelope?
the nucleus is surrounded by a double membrane, known as nuclear envelope.
function:
the nuclear envelope contains many pores that allow movement of molecules between nucleus and cytoplasm.
what is the role of a nucleolus?
a tiny, rounded, darkly-staining body.
function:
it is the site where ribosomes are synthesized.
what is the role of rough endoplasmic reticulum?
has ribosomes attached to the outer surface
function:
ribosomes on the rER are the sites of synthesis of proteins that are packaged into vesicles.
what is the role of smooth endoplasmic reticulum?
no ribosomes
function:
site of synthesis of lipids and steroids, and the reproductive hormones
site of storage of calcium ions in muscle fibres
role of Golgi apparatus?
functions:
site of synthesis of specific biochemicals, such as hormones and enzymes
activates proteins by adding sugars or removing amino acid
role of mitochondrion?
has a double membrane
contains ribosomes
function: site of aerobic respiration and the synthesis of adenosine triphosphate (ATP)
spell out the full spelling of ATP in your head
adenosine triphosphate
role of ribosomes?
found free in the cytosol or bound to the ER
function:
sites where proteins are synthesised in cells
role of vesicles?
they store and transport substances around the cells.
role of chloroplasts?
large organelle occur only in plant cells has a double membrane function: site of photosynthesis by which light is used as the energy source in carbohydrate and adenosine triphosphate (ATP) synthesis.
role of cellulose cell wall?
fully permeable
occur only in plant cells
function:
enclose, support and protect cells
role of large, permanent vacuole?
stores nutrients, absorbs water
role of small, temporary vacuole?
temporary stores of food/water
role of cytoplasm?
site where substances are formed and used in chemical reactions of life
differentiate cell, tissue, organ, system
a group of cells work together to form a tissue.
different tissues combine to form an organ.
several organs work together to make up an organ system.
various organ systems work together to make up an organism.
