D2.1 Cell cycle and control Flashcards
What is cell proliferation?
rapid increase in the number of cells
What is apical meristems?
stem cell tissue in roots and shoots of plants
What’s the longest phase in cell cycle?
Interphase
What’s happens in G1 phase?
Prepare for S phase: cell grows in size and
mitochondria and chloroplast replicate
What happens in S phase?
DNA replication
What happens in G2 phase?
Cell prepares for mitosis: synthesis of microtubules, enzymes and other proteins required for division
Mention two ways that organelles for replication are made
- made by ribosomes
- mitochondria and chloroplast replicate themselves
What are cyclins?
proteins that control the cell cycle
What if the function of cyclins?
Cell must produce cyclins to proceed to another stage of the cell cycle
How cyclins work?
They bind to and activate cyclin-dependent kinases (CDKs), which are enzymes that phosphorylate proteins to produce energy
What is a tumour?
uncontrolled cell division caused by mutation in division controlling genes
What are the division-controlling genes?
-proto-oncogenes
-tumour-suppressor genes
In what ways can mutation of division-controlling genes occur?
- random
- heritable
- mutagenes (toxins, radiation)
What’s the name for proto-oncogenes after mutation?
Oncogenes
What oncogenes do?
are genetically dominant and actively promote cell division
What’s the function of tumour-suppressor genes
they prevent cell proliferation and correct errors due to DNA damage
What’s the result of tumour-suppressor genes mutation?
short, genetically recessive protein
What’s the difference between primary and secondary tumour?
Primary tumours stay in one place, while secondary migrate to other places
What the name for the process of spreading tumour cells?
Metastasis
What are malignant tumour?
tumour capable of metastasising
