Cell Cycle Phases: G1 and S Phase

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What is the purpose of the metaphase checkpoint in the cell cycle?

To signal the start of mitosis

To initiate DNA replication

To ensure that the spindle has formed and all chromosomes are aligned at the equator (correct)

To check for mutations in the DNA

Which molecule is highlighted as the major player in the cell cycle control?

Cyclin (correct)

CDKs

Frequency of cell division

Timothy Hunt

Why do mature nerve cells and muscle cells not divide after maturity?

Due to their high metabolic rate

To conserve energy for other cellular functions

They permanently enter G0 phase (correct)

Because they lack the necessary organelles for division

What happens in malignant tumors?

They metastasize and spread to other parts of the body Signup and view all the answers

In which phase of the cell cycle do skin cells divide frequently throughout life?

S phase Signup and view all the answers

What is the primary reason cells need to divide when they become too large?

To maintain a balance between volume and surface area Signup and view all the answers

Which of the following cells retain the ability to divide but keep it reserved for specific occasions?

Liver cells Signup and view all the answers

What is a characteristic feature of benign tumors?

They are clumped together and can usually be removed Signup and view all the answers

Which step is crucial for almost all transformation efforts?

Selection of efficient transformation techniques Signup and view all the answers

Which technique involves using a gene gun for transformation?

Biolistic - gene gun Signup and view all the answers

Which vector is commonly used in genetic engineering for plant transformation?

Agrobacterium tumefaciens Signup and view all the answers

What is the purpose of evaluating transgenic plants for their effectiveness in alleviating stresses?

To assess their ability to lessen biotic and abiotic stresses Signup and view all the answers

Which method involves the direct transfer of genes into protoplasts?

Protoplast Signup and view all the answers

What is the key process for the development of reliable tissue culture regeneration systems?

Preparation of gene constructs Signup and view all the answers

Which method is NOT commonly used for plant transformation?

Virus vectors Signup and view all the answers

What is the last step mentioned in the text for plant transformation?

Seed infection with Agrobacterium Signup and view all the answers

What is the primary focus of evaluating transgenic plants?

To assess gene expression efficiency Signup and view all the answers

What does the evaluation of transgenic plants aim to avoid in environmental terms?

Being an environmental biohazard Signup and view all the answers