Cell Division , Cell Diversity and Cell differentiation Flashcards
What phases does the cell cycle consist of? and what occurs in each of them
M phase - mitosis occurs after cell growth stops.
G0 phase - This is a resting phase after the completion of cell division. During this the cell may be differentiated or terminated depending on the bodies needs.
G1 - this is the growth phase , organelles duplicate, transcription and proteinsynthesis are performed.
S phase - DNA rapid replicates as the exposed base pairs are more susceptible to the mutagenic changes that may occur that are very dangerous for the organism.
G2 phase - preparation for the next mitosis to occur, cell growth.
What are the 4 stages of mitosis
Prophase - Chromosomes condense , nuclear envelope breaks down and the centriols go to opposite sides.
Metaphase - all the condensed chromatids line up along the equator of the cell and are attached to spindle fibres from opposite ends of the cell from the centrioles.
Anophase - Motor proteins shorten the spindle fibres causing the siste chromatids to pull apart to the poles of the cell.
Telophase - The 2 sets of chromatids uncoil and thin to normal size and a nuclear envelope is formed around each set.
Cytokinesis - the cell is in the final phase where the cellsplits in two creating 2 daughter cells that are identical.
Why is mitosis needed
Growth , repair , asexual reproduction
Why is mieosis needed
variation in gametes by the creation of new alleles from both parents ,male and female. this origneates from the homologuos pairs
What is the definition of a tissue
This is a group of cells that are working together to perform the same function
What are the characteristics of the epithelium tissue
They are made up nearly entirely of cells / the cells are close together and form continuous sheets . they receive nutrients by diffusion and have a smooth surface such as the the squamous that line the capillaries. Also in the cilia they act as one wave wafting mucus. they have short life cycle
what are the 3 types of cartilage:
hyaline - this covers long bones in adults , joins the ribs to the sternum also in the nose, trachea, voice box
fibrous - backbone and knee joint
elastic - arteries
Muscle tissue
They are well vasculaised , made of myofilaments and elongated. the functions are skeletal , cardia, smooth muscle.
what is the key tissue in plants and what is the need for it
The vascular tissue is used to carry water and minerals from the root from the xylem and used to carry minerals and products of photosynthesis that of places of no photosynthesis.
What is the characteristics of meristem cells
They contain stem cells the contents of the cells are that they have thin walls due to the low cellulose no chloroplast small vacuole mitotic and different
What are the functions of the different plant organs
Leaf - photosynthesis
Root - anchor , absorption of minerals and water in the soil , storageof carbon
Stem - structural support , hold the leaves up , contain the xylena and the phloem , storage
flower - sexual repoduction
What are stem cells and what can they do
The stem cells are undifferentiated and then can be used to form any adult cell due to the pluriputency They can also turn on or off all genes, The cell can also be used to produce new cells such as skin and tissue.
How is are these stem cell scourced
they are scourced by embroyonic stem cells , the umbilical cord blood , adukt stem cells are found in decekiped tissue
Stem cells have many potential uses what are some of these
They can be used to treat diseases and to conquer immune differences
Also inside of drug research as drugs can be tested on stem cells as a whole tissue could be developed to test them
they can learn and study about the cell functionality of they can see how the growth occurs and how the cells work
