Cells Flashcards
(45 cards)
what do cells do?
takes nutrients
expel waste
grow and repair themselves
Nucleus
brain of the cell
contains chromosomes
What does chromosomes do?
they contain DNA and this tells the cell how to function. it carries instructions on how to behave and information for protein synthesis
what chemical is the nucleus made up of and what does it produce?
it is made up of RNA (Ribonucleic Acid).
The nucleolus also produces ribosomes used in protein synthesis
cell membrane
also known as the plasma membrane
covered with carbs and these are believed to help the cell recognise other cells.
What is diffusion
particles moving from an area of high concentration > low concentration particles “spreading out”
Simple diffusion
Oxygen and water enter the cell in this way.
Molecules that are soluble in lipids will passively dissolve in the lipid part of the cell membrane and diffuse across it.
Facilitated diffusion
A type of passive diffusion, this is where the substance attaches to a carrier protein to help it cross the cell membrane. this occurs through pores in the cell membrane - these are pores along the membrane that allow small molecules to pass through
Active transport
this form of transport requires a carrier and requires energy to enter the cell as it is moving against the concentration gradient. the energy of the carrier cell(ATP) is used. sodium enters the cell in this way
endocytosis and exocytosis and phagocytosis
cells can ingest materials by engulfing them
endocytosis - engulfed in membrane - particles enter the cell
exocytosis - particles expelled from the cell
phagocytosis - without membrane
what is cytoplasm
fluid that fills inside of the cell. this provides the cell with support
contains glucose, protiens and ions
what is the mitochondria
responsible for cellular respiration
energy extraction from food and the energy is stored as ATP
Lysosomes
they digest material taken in by the cell during phagocytosis and endocytosis
ribosomes
protein synthesis
float freely in the cytoplasm and attach themselves to the endoplasmic reticulum
rough endoplasmic reticulum
transports and adds structure to proteins that have been synthesised by ribosomes
Golgi body
modification of proteins for their final destination
helps in the formation of lysosomes
smooth endoplasmic reticulum
synthesis and transport of lipids and steroids
organelles peroxisomes
bound by a single membrane and they contain enzymes
active process of detoxification
Vacuole
they are filled with cell sap or food
particles, air or water/fluid
its function is to maintain pressure within a plant cell
hold waste and other material
Flagella
an extension of the cell membrane on certain cells to allow propelling moving for example spermatozoa
Cilia
an extension of the cell membrane and allow smaller wavelike movements over the cell surface to move debris and fluid
chromosomes
thread like structure of nucleic acids and protein found in the nucleus, carrying genetic information in the form of genes
Chromatid
each of the two thread like strands into which a chromosome divides during cell division
Centromere
the point on a chromosome by which it is attached
