cell diversity Flashcards
what is a tissue
a group of similar cells that are adapted to carry out the same function
what are the 4 main types of plant tisues
- dermal
- vascular
- ground
- meristematic
what is a dermsl tissue
a single layer of cells that surrounds the different parts of plants
an example of a dermal tisssue
epidermis
what do epidermis cells have
a waterproof layer called a cuticle on its outer surface
what is the function of a dermal tissue
is to protect the plant also to prevent water loss from thr plant
what does the vascular tissue do
transports materials around a plant
what two cells does the vascular tissue consist of
xylem and phloem
what is the structure of the xylem
consits of hollow tubes travelling continuously from the roots to the leaves
what is the main function of the xylem
to transport water and dissolved minerals
what does the phloem cosist of
a series of tube like structures found in leavesstems and roots of plants
what is the function of the phloem
to transport food from the leaves to other parts of the plant
what are the 4 main types of animal tissues
- epithelial
- connective
- muscular
- nervous
what is connective tissue
a tissue that consits of a number of diffrent types of cells spread out in a matrix
an example of a connective tissue and explain
blood because it consists of red cells, white cells and platelets suspended in a matrix called plasma
what is the function of the nervous tissue
carries messages to and from the brain and spinal cord
what are nervous tissues composed of
nerve cells called neurons
what are neurons
they are special cells that are adapted to carry electrical signals
what is tissue culture
the growth of cells in or on a sterile nutrient medium outside an organism
what is it called if it is grown in glassware
in vitro
what are the conditions needed for tissue growth (4)
1.sterile conditions
2.energy source (food)
3.growth hormones
4.optimum temperature
what are the apllications of tissue culture (3)
1.microprpagation
2.cancer research
3. skin grafts
what is microproagation
is the growth of large numbers of plants from very small plant peices eg cells or tissues
what are the benefits of micropropagation (3)
- a large number of plants are produced in a short time
- the plants are genetically identical
- there is no need for pollinators or seeds
what is skin graft
growth of new skin for patients who have been badly burned
what is an organ
a structure composed of a number of tissues that work together to carry out one or more functions
what three tissues does the leaf contain
- dermal
- vascular
- ground
what four types of tissue does the heart contain
- muscular
- epithelial
- connective
- nervous
what is an organ system
consists of a number of organs working together to carry out one or more functions
what is biological organisastion
is the way in which living things are organised
