Module 2: Cellular organisation and Stem Cells Flashcards
What is the order of the levels of organisation in multicellular organisms
specialised cells
tissues
organs
organ systems
organism
What is a tissue
What is an organ
What is an organ system
a group of specialised cells that all have the purpose of performing a particular function
a group of tissues that work to perform a wider function
a group of organs that work together to perform an essential life function
What are the 2 tissue types commonly found in plants
xylem tissue and phloem tissue
What is the function of xylem tissue
What is its structure 3
Where is xylem tissue produced
to transport water and minerals as well as providing structural support
they are long cylinders made of dead tissue with open ends , they are thickened by a tough substance called lignin
produced by meristem cells
What is the phloem tissue involved in?
Where and how is it produced
3
its involved in translocation
it is produced by meristem tissue , it produces cells that elongate and line up end to end to form a long tube
their ends produce perforated structures called sieve plates and metabolically active companion cells are found next to the plates and help to mediate the movement of photosynthesis products in the tubes
What is translocation
the movement of food substances and nutrients from leaves to storage organs and growing parts of the plant
What is the composition of epithelial tissue
What are the 2 types
a sheet of cells that lines or covers a surface
squamous and ciliated
What is the composition of squamous epithelial tissue and where is an example of its location
-cells produce a very smooth , flat and thin surface where they are packed tightly together
EG-lining of blood vessels and cheeks
What is the composition of ciliated epithelial tissue and where is an example of its location
-composed of column shaped cells containing cilia which form from the lining
-the trachea and bronchi
What are the 4 main tissue types in animals and how are they specialised
nervous-adapted to support transmission of electrical impulses
epithelial-adapted to cover a body surface
muscle-adapted for movement through contraction
connective-adapted to hold other tissues together or to act as a transport medium
What is a stem cell
an undifferentiated cell that has the ability to specialise and become any type of cell
What is the process by which stem cells specialise called and what happens to them once they become specialised
differentiation
they become adapted to their role and lose their ability to divide
What are the 3 different types of stem cell
totipotent
pluripotent
multipotent
What can a totipitent stem cell do
differentiate into any type of cell including placental cells , they have the ability to form an entire organism
What can pluripotent stem cells do
differentiate into any type of cell excluding placental cells so they cant form an entire organism
