cells and Tissues Flashcards
structure and function of the endoplasmic reticulum
continuous folds of membrane
2 types:
1. rough endoplasmic reticulum
- surface covered in ribosomes
- processes proteins made by ribsomes
2. smooth endoplasmic reticulum
- tubular appearance
- no ribosomes
- production, processing and storage of lipids,
carbs and steroids
structure of lysosomes
spherical sac surrounded by a membrane, contains hydrolytic enzymes
function of lysosomes
- destroy foreign material in or outside the cell
- breakdown material ingested by phagocytic cells
- releases enzymes
- digests worn out organelles by a process called autophagy
- breaks down cells after they died
structure and function of the golgi apparatus
flattened sacs of membrane
modifies and packages proteins into air sacs, either vesicles or lysosomes
what are microfilaments
within the cytoplasm, a network of 2 different types of protein fibres:
1. microfilaments
2. microtubules
these fibres can cause cell movement and movement of organelles within the cells by moving against each other
structure and function of centrioles
a pair of short hollow cylinders found near the nucleus. move chromosomes around by forming fibres called spindle during cell division
structure and function of flagella
tail like extention of the cell, made of longer microtubules. contract to provide cell movement
structure and function of cilia
hair like projections made from microtubules
allows for movement of substances over the cell surface
structure and function of vacuole
surrounded by a membrane, filled with clear liquid, very small in animals, bigger and permanent in plants.
for storage of nutrients, proteins or dangerous substances
structure of the cell / plasma membrane
formed from a phospholipid bilayer of phospholipids spanning a diameter of about 10nm
function of the cell / plasma membrane
selectively permanent barrier, contols the exchange of materials between the internal and external cell environment
allows for cell communication
structure and function of cytoplasm
made of cytosol, about 80% water. all organelles contained within it.
serves as a medium for chemical reactions and provides structural support for organelles
structure and function of nucleus
largest organelle, surrounded by a membrane.
control centre of cell, contains genetic material. amkes ribonucleic acid and ribosomes
structure of mitochondria
double membrane, inner membrane folded to create large surface area. contains enzymes needed for aerobic respiration and producing ATP. also contains dna and ribosomes
function of mitocondria
site of aerobic respiration, produces energy
what is ATP
adenosine triphosphate, the energy “currency” needed for all cells in the body
structure of ribosomes
consists of RNA and proteins. each ribosome is composed of 2 subunits, a larger and smaller part. found in the cytoplasm or RER
function of ribosomes
responsibe for protein synthesis by translating genetic code from the nucleus into proteins
structure of muscle cells
when the muscle contracts all of the induvidual cells also contract. muscle cells are elongated and have protein fibers shat can shorten the cell
structure of red blood cells
really small to fit through capillaries
huge sa:v
no nucleus to make more room for heamoglobin
structure of nerve cells
long cytoplasmic extention called nerve fibres to carry electrical impulses
structure of root hair cells
cytoplasmic extentions from cells to outside of root, these extentions increace the surface area for optimal absorbtion
structure of xylem cells
elongated cells placed end to end to form long tubes. no end walls. strengthened with lignin. dead cells
structure of phloem cells
living cells, consists of sieve tubes, phloem fibres and phloem parenchema cells with companion cells providing the sieve tubes with energy
