cells Flashcards
what is the cell cycle?
set of steps that take place in cell division
what is an organelle?
part of a cell and they all take part in the cell cycle
what cells have a fast cell cycle?
hair, blood, skin, digestive cells
what are the 3 stages of the cell cycle?
interphase
mitosis
cytokinesis
what is a cell?
the smallest functional unit of life that can function on its own
what does semi-permeable mean?
only lets certain things through into the cell (oxygen and carbon dioxide)
what is the cell membrane?
semi-permeable boundary between a cell
control of substance in and out of the cell
site of antigens
what is a lipid bilayer?
allows small molecules through large molecules
what is transcription?
a specific section of the cells DNA is ‘copied’ using a molecule of mRNA
what is translation?
ribosomes take mRNA and use it as a blueprint to create a new molecule
what are rough endoplasmic reticulums?
covered in ribosomes; sends proteins to destination
what are smooth endoplasmic reticulums?
lacks ribosomes; detoxify cells and transport proteins
what are golgi apparatus?
protein received from the ER are further processed to their destination
what is exocytosis?
contents of a cells vacuole are released into the exterior
what are lysosomes?
specialised vesicles that contain powerful enzymes
what do mitochondria do?
generate energy for their host cell using the process of aerobic respiration
what does aerobic respiration produce?
uses glucose molecules and oxygen to generate ATP
what are 4 types of filament in the cytoskeleton?
actin, intermediate, microtubles, centrioles
what are actin/microfilaments?
fine thread like structures allowing the cell to change shape and contract
what are intermediate filaments?
slightly thicker and provide tensile strength
what are microtubules?
hollow tubes act as a scaffold for the cell and provide sets of ‘tracks’ for organelles and vesicles to move along
what are centrioles?
organise the cells microbes and also produce the cilia and flagella in cells which feature them
what is diffusion?
the movement of particles from an area of high to low concentration
what is osmosis?
the net movement of water from an area of high to low water potential
what is facilitated diffusion?
happens by channel or carrier proteins
what is a eukaryotic cell?
plant, yeast, animal
what is a prokaryotic cell?
bacteria
what is the specialised function of the ova?
Cytoplasm contains nutrients for growth of the developing embryo.
Zona pellucidia (barrier to prevent sperm)
Corona Radiata (supply nutrients to cell)
what is the specialised function of sperm cells?
fertilisation of the female egg
what is the specialised function of neurone cells?
responsible for transmitting electrical and chemical signals in the nervous system
what are the specialised function of squamous epithelial cells?
boundary cells
single layer (capillaries) or multiple layers (skin)
flat, scale shaped
what is the specialised function of striated muscle cells?
long multi-nucleated cells
attached to bone by tendons
under conscious control
contract
what is chromatin?
long entangled structures of chromosomes
what are chromosomes?
chromatin condenses to make chromosomes which consist of DNA
why do cells need to divide?
to replace dead cells for growth and repair
