Activities Key Terms Quizzes Art Chapter 8 Self-Quiz
Unit 2: Cell: The Basic Units of Life Photosynthesis and Respiration Review
  1. Photosynthesis is the metabolic process in plants and algae that captures energy and uses it to turn CO2 and H2O into sugars (glucose). The process is compartmentalized in the and produces as a by-product.
  2. Respiration is the series of reactions that uses the O2 and glucose made during photosynthesis to manufacture for cellular work, with and produced as by-products of the process. The breakdown of food molecules in this process is called aerobic . Many of the reactions of respiration are compartmentalized in .
  3. The temporary storage and transfer of energy in both photosynthesis and respiration require the use of reduced electron carriers such as and .
  4. Photosynthesis occurs in the chloroplast in two stages.
  5. The reactions occur on the membranes which separate the from the .
    • Pigments such as and , and (ETCs) are used to capture solar energy, excite electrons, and manufacture NADPH and .
    • The "excited" electrons are captured by the complex and are transferred from the chlorophyll to the ETC in Photosystem .
    • Photosystem receives the excess electrons and forms NADPH. A channel protein pumps protons into the space, and are moved into the by ATP synthase, producing .
  6. The reactions of photosynthesis occur in the of the chloroplast.
    • Products of the light reactions are used to energize CO2 and make the sugar monomer in a process known as carbon .
    • is the source of energy, while is the source of high-energy electrons.
    • Other products of the dark reaction include the sugar polymers and .
  7. Respiration occurs in three stages.
  8. First, glycolysis takes place in the and begins the breakdown of to produce and small amounts of and . In the absence of O2, the pyruvate made during glycolysis enters the anaerobic respiration of fermentation, which produces and either or acid.
  9. Next, if O2 is present, aerobic respiration takes place. Pyruvate is directed to the inner matrix of the , where it enters the citric acid cycle. is released as the pyruvate is degraded, yielding a few additional ATP and numerous molecules of NADH.
  10. Finally, the electrons in NADH and O2 are used during oxidative phosphorylation (which occurs on the mitochondrial inner membrane) to manufacture more than 30 molecules of ATP, again through the and using . In this process is required and is released.

Activities Key Terms Quizzes Art Chapter 10 Self-Quiz
Unit 2: Cell: The Basic Units of Life Cell Division Review
  1. Eukaryotic cells multiply by dividing to form cells in a process called the division cycle. An undifferentiated cell that can divide to produce one or more cell types is called a cell.
  2. In the nucleus, DNA is packed with protein in strands called . During cell division, chromatin is condensed into visible bodies called . Each species has a unique of specific number and shape of chromosomes. Humans have 46 chromosomes consisting of 22 pairs and 2 chromosomes.
  3. In cells, the actively dividing state is , while the period between mitotic division is . Each daughter cell receives the full complement of DNA of the parent cell and is genetically identical to the parent; this is called DNA and requires DNA .
  4. Interphase prepares the cell for division and is composed of 4 sub phases.
    • In the phase, the cell prepares for the DNA synthesis by producing necessary and and growing in size.
    • In the phase DNA synthesis occurs to prepare for DNA . Each strand of DNA is duplicated to form the two arms of of the chromosomes, held together by , each of which has two .
    • In the phase, the cell prepares for mitosis by producing another set of proteins.
    • The phase is a resting alternative to the G1 stage where cells do not prepare for mitosis. Most somatic cells are in this phase when they reach maturity.
  5. Mitosis is composed of 5 sub phases.
    • In , chromatins condense into , move toward , and microtubules form the mitotic .
    • In , the nuclear breaks down, and the spindle microtubules connect kinetochores to opposing .
    • In , chromosomes line up in the middle of the cell called the metaphase , or equatorial plate.
    • In , DNA occurs when sister separate at the kinetochore and the daughter move toward the centrosomes at the poles.
    • In , spindle microtubules break down, nuclear form around the new chromosomes, and the chromosomes unfold to their interphase state. In plants, vesicles fuse to form a new cell . In , actin filaments divide the cell in two. In plants, new cell formation is completed.
  6. Germline cells in undergo ; each diploid parent cell yields four haploid . The union of a male gamete called a and a female gamete called an results in a diploid . This process of sexual reproduction is called . The gender of a human zygote is determined by the .
  7. Meiosis consists of two nuclear divisions, meiosis I and meiosis II.
    • In meiosis I, homologous chromosomes form pairs of . Microtubules from only one pole attach to each chromosome of a homologous pair, and each daughter cell receives only one of the pair. This division produces two haploid cells, each with two chromatids on each chromosome.
    • In meiosis II, the two in each daughter cell separate. The result is four haploid gametes.
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