Chromosomes, Genes And Proteins (continued)
Overview
A gene is only useful if its instructions can be carried out. This Extended lesson follows how DNA, locked safely in the nucleus, actually controls a cell by directing the making of proteins, and how a messenger molecule carries the code out to where proteins are built.
You will explain how DNA controls cell function through the proteins it makes, outline how a protein is assembled using mRNA and ribosomes, see why cells with the same genes can be so different, and define the haploid and diploid numbers of chromosomes, including the 23 pairs in a human cell.
Objectives
- [Supplement] Explain that DNA controls cell function by controlling the production of proteins, including enzymes, membrane carriers and receptors for neurotransmitters
- [Supplement] Explain how a protein is made, limited to: the gene coding for the protein remains in the nucleus messenger RNA (mRNA) is a copy of a gene mRNA molecules are made in the nucleus and move to the cytoplasm the mRNA passes through ribosomes the ribosome assembles amino acids into protein molecules the specific sequence of amino acids is determined by the sequence of bases in the mRNA (knowledge of the details of transcription or translation is not required)
- [Supplement] Explain that most body cells in an organism contain the same genes, but many genes in a particular cell are not expressed because the cell only makes the specific proteins it needs
- [Supplement] Describe a haploid nucleus as a nucleus containing a single set of chromosomes
- [Supplement] Describe a diploid nucleus as a nucleus containing two sets of chromosomes
- [Supplement] State that in a diploid cell, there is a pair of each type of chromosome and in a human diploid cell there are 23 pairs
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Lesson Evaluation
Congratulations on completing the lesson on Chromosomes, Genes And Proteins (continued). Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- DNA controls the function of a cell by controlling the production of: A. water B. proteins C. carbon dioxide D. mineral ions Answer: B
- Where is mRNA made? A. in the cytoplasm B. in the ribosome C. in the nucleus D. in the cell membrane Answer: C
- Which structure assembles amino acids into a protein? A. nucleus B. ribosome C. mitochondrion D. chromosome Answer: B
- A human diploid cell contains: A. 23 chromosomes B. 23 pairs of chromosomes C. 46 pairs of chromosomes D. a single set of chromosomes Answer: B
- Two body cells contain the same genes but make different proteins because: A. they have different DNA B. only the genes they need are expressed C. they are haploid D. ribosomes differ between cells Answer: B
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