1.2 Cell Structures Flashcards
function of ribosomes
involved in protein synthesis
what are ribosomes made from
They are made of a large and a small subunit
constructed from rRNA and protein.
amounts of ribosomes in prokaryotes and eukaryotes
70s in prokaryotes
80s in eukaryotes
endoplasmic reticulum
series of flatted sacs
double membraned cisternae leading on from the nuclear envelope.
RER
covered in ribosomes for protein synthesis; cisternae then transport the protein
SER
Synthesis and transport of lipids
vacuole
Contains cell sap and is surrounded by the
tonoplast membrane.
cell wall
A structure made from cellulose microfibrils
and pectin.
* It is fully permeable for the transport of
substances.
* It provides strength to the plant.
* It communicates through the cell wall via
plasmodesmata.
golgi body
The golgi body modifies and packages
proteins. It also:
* produces secreting enzymes
* secretes carbohydrates
* produces glycoproteins
* transports and stores lipids
* forms lysosomes and digestive
enzymes.
centrioles
Only found in animal cells. They are 2
cylinders of microtubules that form the
spindle in cell division.
what is the cell theory
Cell theory states that new cells are
formed from other existing cells
what type of cells are animals and plants ?
eukaryotic
what do eukaryotic cells contain?
- membrane bound organelles
- DNA
- cell walls are made from cellulose
- ribosomes are 80s
- aerobic respiration takes place within mitochondria
nuclear envelope
A double membrane with pores that allows mRNA and ribosomes out of the nucleus.
chromatin
DNA coils bound to protein codes for
protein synthesis.
nucleolus
rRNA and ribosomes are made here
function of mitochondria
Aerobic respiration occurs in the
mitochondria.
structure of mitochondria
They are cylindrical in shape for a large surface area and reduced diffusion distance. the inner membrane is folded into cristae. The cristae have stalked particles involved in ATP synthesis. The cristae increase the surface area for ATP synthesis.
chloroplast
contain chlorophyll, a pigment that traps light energy for photosynthesis.
chlorophyll
contain chlorophyll, a pigment that traps light energy for photosynthesis.
what type of cell is bacteria ?
prokaryote
prokaryotes contain …
no membrane bound organelles
difference between prokaryotes and eukaryotes
PROKARYOTES
DNA free in the cytoplasm
Ribosomes 70s
Peptidoglycan cell wall
Mesosome for aerobic
respiration
EUKARYOTES
DNA in nucleus
Ribosomes 80s
Cellulose cell wall
Mitochondria for aerobic
respiration
virus
A virus is not a living thing; it is not a cell. It
has no cytoplasm or organelles. It injects its
genetic material into a living cell which then
creates more virus particles
what is used to view eukaryotic and prokaryotic cells ?
light microscope
define the term tissues
A group of cells with the same
structure and function working
together.
epithelial tissue
continuous layers of cells on internal and external surfaces
cuboidal tissue
simplest, one cell thick, e.g. PCT kidney
columnar tissue
elongated, can have cilia e.g. trachea
squamous tissue
flattened e.g. alveolar wall
muscle tissue
tissue that is able to contract
skeletal
striated (striped), voluntary,attached to bones
for locomotion
smooth
spindle-shaped cells, no stripes, involuntary e.g.
skin and digestive tract
smooth
spindle-shaped cells, no stripes, involuntary e.g.
skin and digestive tract
cardiac
heart muscle, striated, short fibres,
contracts without nerve stimulation.
Does not tire
connective tissue
separates tissues and organs
Elastic and collagen
Blood, bone and
cartilage
organ
A group of tissues working together to
perform a particular function.
organ system
A system of organs working together with a
particular role.
organism
All the systems working together form a
discrete individual.
