Unit 3: Mitosis and Meiosis

Question

1. Draw a diagram of Mitosis with labels

2. Draw-a-diagram of Meiosis with labels

3. Create a T-chart to compare/contrast Mitosis and Meiosis

4. Define Diploid and Haploid.

Create a word problem for each scenario: diploid to diploid, diploid to haploid, and haploid to diploid

5. Why is crossing over important?

6. Draw a diagram of the cell cycle and describe each step

7. Explain in a paragraph how mitosis and meiosis maintain genetic continuity?

Unit 4: DNA, RNA, DNA Replication, Protein Synthesis

1. Create a Venn Diagram to Compare and Contrast DNA and RNA

2. Draw a picture to represent DNA Replication.

Why is this process important?

What enzymes are involved?

• Explain what semiconservative means.

3. What is the purpose of Transcription? Where does it take place in the cell?

4. What is the purpose of Translation? Where does it take place in the cell?

5. Describe the 3 types of RNA

6. Determine the sequence of amino acids produced by this DNA sequence: CATGGACGC

Make it seem like a 9th grader wrote it

Answer 1

Unit 3: Mitosis and Meiosis

1. Diagram of Mitosis with Labels

(Since I can't draw, imagine a circle representing a cell nucleus.)

1. Prophase: Chromosomes condense and become visible.
2. Metaphase: Chromosomes line up in the middle of the cell.
3. Anaphase: Sister chromatids separate and move to opposite ends.
4. Telophase: Nuclear membranes reform around the two sets of chromosomes.
5. Cytokinesis: The cell membrane pinches in and two identical daughter cells are formed.

2. Diagram of Meiosis with Labels

(Picture two rounds of division with some crossing over happening between homologous chromosomes.)

1. Prophase I: Homologous chromosomes pair up and exchange segments (crossing over).
2. Metaphase I: Paired chromosomes line up in the center.
3. Anaphase I: Homologous chromosomes are pulled apart to opposite sides.
4. Telophase I: Two nuclei form, and cytokinesis occurs.
5. Prophase II: A new set of spindle fibers forms.
6. Metaphase II: Chromosomes line up in the center again.
7. Anaphase II: Sister chromatids are pulled apart.
8. Telophase II: Nuclei form around each set of chromosomes, resulting in four haploid cells.

3. T-Chart to Compare/Contrast Mitosis and Meiosis

| Mitosis | Meiosis | |-----------------------------------------|----------------------------------------| | Produces 2 identical diploid cells | Produces 4 unique haploid cells | | One round of cell division | Two rounds of cell division | | Involves one division of the nucleus | Involves two divisions of the nucleus | | Used for growth and repair | Used for producing gametes | | No crossing over occurs | Crossing over occurs |

4. Define Diploid and Haploid

• Diploid (2n): A cell that contains two complete sets of chromosomes, one from each parent. For example, human cells (except gametes) have 46 chromosomes, which is diploid.

• Haploid (n): A cell that has only one set of chromosomes. Gametes, like sperm and eggs, are haploid and have 23 chromosomes.

Word Problems:

1. Diploid to Diploid: A skin cell in your body undergoes mitosis. If it starts with 46 chromosomes, how many chromosomes will each new skin cell have after division?

   Answer: Each new skin cell will have 46 chromosomes.

2. Diploid to Haploid: In a human male, a cell undergoes meiosis to produce sperm. If the original cell has 46 chromosomes, how many chromosomes will each sperm cell have?

   Answer: Each sperm cell will have 23 chromosomes.

3. Haploid to Diploid: During fertilization, a sperm cell (23 chromosomes) and an egg cell (23 chromosomes) combine. What is the total number of chromosomes in the new zygote?

   Answer: The zygote will have 46 chromosomes.

5. Why is Crossing Over Important?

Crossing over is important because it increases genetic diversity. It occurs during Prophase I of meiosis, where homologous chromosomes exchange segments. This process creates new combinations of genes, which can lead to a greater variety of traits in the offspring. Genetic diversity is essential for evolution and species adaptation.

6. Diagram of the Cell Cycle and Describe Each Step

(Picture a big circle with labeled sections for each phase.)

1. G1 Phase (First Gap): The cell grows and carries out normal functions.
2. S Phase (Synthesis): DNA is replicated, so the cell now has two copies of each chromosome.
3. G2 Phase (Second Gap): The cell continues to grow and prepares for mitosis.
4. M Phase (Mitosis): The cell divides its copied DNA and cytoplasm to form two new cells.

7. Explain How Mitosis and Meiosis Maintain Genetic Continuity

Mitosis and meiosis are critical for maintaining genetic continuity in living organisms. Mitosis creates two identical diploid cells, ensuring that each new cell has the same genetic material as the original cell. This is essential for growth and repair. On the other hand, meiosis produces haploid gametes that contain half the chromosome number, and when fertilization occurs, these gametes combine to restore the diploid chromosome number. This process promotes genetic variation through recombination and crossovers during meiosis, which also helps ensure that the next generation has a mix of traits, supporting adaptation and evolution.

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Unit 4: DNA, RNA, DNA Replication, Protein Synthesis

1. Venn Diagram to Compare and Contrast DNA and RNA

(Imagine two overlapping circles.)

• DNA:

  • Double-stranded
  • Deoxyribonucleic acid
  • Contains thymine
  • Stores genetic information

• RNA:

  • Single-stranded
  • Ribonucleic acid
  • Contains uracil instead of thymine
  • Involved in protein synthesis

• Both:

  • Made of nucleotides
  • Contain adenine, guanine, and cytosine

2. Picture to Represent DNA Replication

(Imagine a DNA helix unwinding and each strand serving as a template for a new strand.)

Why is this process important? DNA replication is essential because it ensures that when cells divide, each new cell has an exact copy of the DNA. This is crucial for growth and maintaining functions in living organisms.

Enzymes Involved:

• Helicase: Unwinds the DNA double helix.
• DNA Polymerase: Synthesizes new strands by adding complementary nucleotides.

Explain what semiconservative means: Semiconservative means that when DNA replicates, each new double helix consists of one original strand and one newly synthesized strand. This method helps preserve the genetic information.

3. What is the purpose of Transcription? Where does it take place in the cell?

The purpose of transcription is to create a complementary RNA copy of a segment of DNA. This RNA copy, called messenger RNA (mRNA), carries the genetic instructions from the DNA to the ribosomes where proteins are made. Transcription takes place in the cell nucleus.

4. What is the purpose of Translation? Where does it take place in the cell?

The purpose of translation is to decode the mRNA sequence to synthesize proteins. Ribosomes read the mRNA and use transfer RNA (tRNA) to bring the right amino acids together to form proteins. Translation occurs in the cytoplasm at the ribosomes.

5. Describe the 3 Types of RNA

1. mRNA (messenger RNA): Carries the genetic blueprint from DNA in the nucleus to the ribosomes in the cytoplasm for protein synthesis.

2. tRNA (transfer RNA): Brings the appropriate amino acids to the ribosome as specified by the mRNA sequence during protein synthesis.

3. rRNA (ribosomal RNA): Combines with proteins to form ribosomes, the site of protein synthesis, and helps facilitate the translation process.

6. Determine the Sequence of Amino Acids Produced by This DNA Sequence: CATGGACGC

To find the amino acid sequence, first, transcribe the DNA to mRNA:

• DNA: CATGGACGC
• mRNA: GUACCUCGC

Now, using the codon chart, we translate the mRNA:

• GUA → Valine (Val)
• CCU → Proline (Pro)
• CGC → Arginine (Arg)

So, the sequence of amino acids produced is Val-Pro-Arg.

Answer 2

Can you shorten 5 and 6 for unit 4? Like summarize?

Answer 3

Sure! Here’s a summarized version of 5 and 6 for Unit 4:

5. Why is Crossing Over Important?

Crossing over is crucial because it increases genetic diversity during meiosis. It occurs when homologous chromosomes exchange segments of DNA, creating new combinations of genes. This variation is vital for evolution and can lead to better adaptation of species over time.

6. Determine the Sequence of Amino Acids Produced by This DNA Sequence: CATGGACGC

To translate the DNA sequence CATGGACGC into amino acids:

1. Transcribe to mRNA: GUACCUCGC
2. Use a codon chart to find corresponding amino acids:
   • GUA → Valine (Val)
   • CCU → Proline (Pro)
   • CGC → Arginine (Arg)

So, the resulting amino acid sequence is Val-Pro-Arg.