Organelle
a specialized structure within a cell that has a specific function
Cell
the smallest structural unit of an organism that is capable of independent functioning
Cell Wall
a layer that surrounds some types of cells and gives strength and support; plant cell walls are made of cellulose
Cytoplasm
all of the material, except for the nucleus, that is found within a cell
cell surface membrane
a biological membrane that separates the internal contents of a cell from its external environment
nucelus
membrane bound organelle that contains the genetic material of a cell
chloroplast
the photosynthetic organelle in eukaryotes
mitochondrion
the organelle in eukaryotes in which aerobic respiration takes place
Golgi body
cell organelle that modifies proteins
light microscopes
a type of microscope that uses visible light and glass lenses to magnify structures
electron microscope
a type of microscope that uses electrons and electromagnets to magnify structures
rough and smooth endoplasmic reticulum
a network of flattened sacs running through the cytoplasm or eukaryotic cells; molecules, particularly proteins, can be transported through the cell inside the sacs separate from the rest of the cytoplasm; ER is continuous with the outer membrane of the nuclear envelope
magnification
the process of enlarging the size of an image
resolution
the smallest distance between two points that can be detected; it is a measure of the level of detail that can be seen
wavelength
he distance between two corresponding points of a wave; different colours of light have different wavelengths
nucleoli
small circular areas inside the nucleus that produce RNA for ribosomes
Ribosomes
small organelles that are involved in the synthesis of proteins
Chromatin
DNA, RNA, and protein, located within the nucelus of cells
cisternae
flattened membranes of the Golgi body and endoplasmic reticulum
vesicle
small structures that consist of fluid surrounded by a membrane; they are used for transporting substances around cells
steroid hormones
steroid molecules that are used as hormones
oestrogen
a steroid hormone that is the primary female sex hormone
Testosterone
a steroid hormone that is the primary male sex hormone
lysosomes
membrane enclosed organelles that contain digestive enzymes
cristae
folds of the inner mitochondrial membrane; they are involved in aerobic respiration
matrix
he fluid filled space within the inner mitochondrial membrane; it contains enzymesand sugars involved with respiration
stroma
the liquid substance in the centre of chloroplasts, surrounding the thylakoid membranes; it is where the light independentstage occurs
thylakoid membranes
membrane bound structures in the stroma of chloroplasts; stacks of thylakoids are called grana; they are where the light dependent stage of photosynthesis occurs
grana
areas in the stroma of chloroplasts where thylakoid membranes containing photosynthetic pigments are stacked on top of each other
photosynthesis
the process of using light energy to synthesise glucose from carbon dioxide and water to produce chemical energy
DNA
he molecule that is used as hereditary material being passed onto subsequent generations; it contains the code for all the genes of organisms
Cellulose
an important component of plant cell walls which is made from many straight chains of glucose molecules held together by hydrogen bonds
B-glucose
an isomer of the sugar, glucose; it is the monomer that cellulose is made up of
middle lamella
The outer layer of a cell wall and is mainly composed of calcium pectate. Calcium pectate is like a glue which bonds plants cells to their neighbours. It is the substance that helps fruit jams to set.
large permanent vacuole:
a membrane bound organelle that is present in all plant and fungal cells; it contains cell sap
tonoplast
the membrane found outside a large permanent vacuole in plant and fungal cells
cell sap
the fluid located inside a large permanent vacuole
fluid mosaic model
a model that explains the properties of cell membranes
Glycerol
a simple molecule that is a constituent of triglycerides and phospholipids
nonpolar
molecules that do not have electric charge
hydrophobic
substances that will not mix with water; they will not dissolve in water
hydrophilic
substances that are attracted to water molecules; will dissolve in water
carrier proteins
membrane proteins that are involved in the transfer of substances from one side of membranes to the other; they possess a specific binding site to which substances bind and change shape as the substance is moved across the membrane
channel protein
membrane proteins that are involved in the transfer of substances from one side of membranes to the other; contain a pore through which substances will pass through