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Chapter 9 Test Study Guide: Cell Reproduction
Abdulaziz AlObaidi
Test date: Thursday Nov 17
Format: MCQ, Labeling, Short Answers, Matching
Chapter 9 Section 1: Cell Size
Notes Link Powerpoint Link Surface Area To Volume Notes
Vocabulary: Quizlet
Cell Size: smaller cells are more efficient than large ones. Surface Area: measurement of the outer surface of an object Volume: amount of space an object takes up Surface area to volume ratio: ratio of cell’s outside area to internal volume. Cell Division: process by which a cell divides into 2 new daughter cells Binary Fission: a form of asexual reproduction in which one cell divides into 2. ( prokaryotic cells) Cell Cycle: sequence of events in which a cell grows, prepares for division, and divides to form 2 daughter cells. Daughter Cells: cells that are produced as a result of mitosis, are identical, and original to parent cell. Parent Cell: original cell before division. Mitosis: when the cell nucleus divides in somatic cells. Somatic Cells: body cells Meiosis: cell division that results in cells with half of the chromosomes; in reproductive cells. Interphase: Cell grows, performs its normal functions, and prepares for division; consists of G1, S, and G phases Gap 1 Phase: stage of interphase in which cell grows and performs its normal functions Synthesis Phase: DNA replication.
Gap 2 Phase: duplicates its cytosol and organelles Cytokinesis: division of cytoplasm in cell division Chromosomes: bodies in nucleus made from DNA and proteins (histones) used to store genetic info. Chromatin: uncoiled form of DNA. Chromatid: half of chromosome. Centromere: area where chromatids are attached. Cleavage Furrow: draws plasma membrane toward cell center pinching the cytoplasm into two lobes. ( animal) Cell Plate: in plant midline of dividing cells, becomes the cell wall. Topics To Know
- Why are cells small? ● Cells are small for two reasons: Substance Transport:
- Not enough material will be able to cross fast to accommodate cell volume.
- Transport of nutrients & waste by diffusion slows down
- Small cells maintain more efficient transport systems Cell Communication:
- Signaling proteins need to move around
- Affects the ability of the cell to communicate instructions to cellular functions.
- Why small cell are more effective in transporting nutrients and removing waste (surface area to volume ratio) As a cell increases in size, both surface area and volume increase but the volume increase at a faster rate, this means that the big cell might have difficulty supplying nutrients and getting rid of waste, while the smaller easier.
- What is the difference between prokaryotic cell division and eukaryotic cell division
Notes Link Powerpoint Link
Vocabulary: Quizlet
Mitosis: Cell division when nucleus divides into two nuclei containing the same number of chromosomes ending in 2 identical cells Meiosis: Prophase: Mitosis begins; centrioles that contain spindle fibers appear and begin to move to opposite ends of cell. The DNA condenses and becomes more visible. The Nucleus begins to disappear Metaphase: “Middle” Spindle Fibers attach to chromosomes from the centromere and line up in the middle of the cell Anaphase: “Away” Chromatids separate, begin to move to opposite ends, pulled by the spindle fibers Telophase: “ Twin” Cell membrane pinches inward to create two daughter cells - each with own nucleus with identical genetic information Spindle Fibers: String like structures that connect to centromeres and pull apart chromosomes: Spider-Man Webs" Centrioles: organelles that produce spindle fibers. Chromosomes: coiled and packed DNA Chromatin: uncoiled form of DNA. Sister Chromatids: half of a chromosome. Nuclear Envelope: membrane that surrounds the nucleus. Cleavage Furrow: forms in animal cell to split the cell Cell Plate: forms in a plant cell to split the plant cell Parent Cell: original cell Centromere: thing that connects chromatids.
Topics To Know
- Understand the importance of mitosis
- Growth : increases the number of cells
- Repair : heals and repairs damaged tissue
- Maintain Cell size
- Understand the steps of mitosis Prophase:
- DNA thickens; becomes chromosomes
- Nucleus begins to disappear
- Centrioles move to opposite side
- Spindle fiber forms and attach to chromosome at centromere Metaphase:
- Chromosomes line up along the middle of the cell
- Pulled to the middle by the movement of spindle fibers Anaphase:
- Centromeres divide chromatids move to opposite sides
- Cell stretches out bcz of chromatids moving Telophase:
- Nuclear envelope forms at each pole
- Chromosomes become chromatin
- Spindle fibers dissolve
- Cell pinches forming a cleavage furrow in animals and cell plate in plant cell
- Cytokinesis begins
- Know what happens in each stage as well as drawing the stages and labeling them
Topics To Know
1. Why cell regulation is important during cell division?
Cell regulation is important to cell division
- it can catch mistakes in duplication that can lead to mutations that
ultimately lead to cancer.
- Check whether the cell is big enough and has enough proteins and nutrients
for the next phase
- Check to see if DNA is duplicated
- Check to see if the spindle fiber is attached to chromosome
2. The three different types of checkpoints and what they do
1. G1 Checkpoint : checks for DNA integrity, Cell size, nutrients, and
growth factors.
2. G2 Checkpoint : checks for DNA damage, and allows for repair of
DNA.
3. Spindle Assembly Checkpoint : checks for chromosome attachment to
mitotic spindle.
3. What is cancer?
- A disease in which cells divide uncontrollably
- damaging cells by overcrowding
- Interrupts cell cycle
- Spend less time in interphase causing them to grow and divide more
quickly
4. What are the causes of cancer ( including environmental and
non-environmental)?
Non-environmental causes: Age and genetics.
Environmental causes: UV light, tobacco, radiation, pollution, processed food,
and alcohol.
5. Why does a cell go through apoptosis? Give an example of how apoptosis can
be important.
- Apoptosis is programmed cell death;
- happens to get rid of damaged (abnormal) cells that lead to cancer.
- E.g: the separation of fingers and toes in the human embryo.
6. What are stems cells and why are they important
Stem cells are unspecialized cells that can develop into specialized cells under the
right conditions. They are important because of their potential to repair, restore,
and regenerate cells.
7. Know the difference between embryonic stem cells and adult stem cells
Embryonic Stem Cells Adult Stem Cells
- Found from cells found in
embryos
- Found from cells found in
specific tissues
- Can be differentiated in any
specialized cell
- Cannot be differentiated into
any specialized cell
- Can be made to be used in any
type of specialized cell
- Can only be used in cells from
the same type of tissue
- Can be divided many times. - Decrease in number and activity
as one ages.
Cytokinesis 1: Cytoplasm splits, resulting in 2 cells that must divide again Prophase 2 : Chromosomes condense, spindles form in each new cell, and spindle fibers attach to chromosomes. Metaphase 2 : Centromeres of chromosomes line up randomly at the equator of each cell. Anaphase 2 : sister chromatids separate and move to opposite poles Telophase 2: A nuclear membrane forms around the chromosomes in each of the 4 new cells. Cytokinesis 2 : Cytokinesis splits the chromosome sets into new cells, forming the final products of meiosis: four haploid cells in which each chromosome has just one chromatid. In humans, the products of meiosis are sperm or egg cells. Sperm Cell: male reproductive cell Egg Cell: The female reproductive cell. Plural of ovum = ova Spores: Produced by meiosis of plant cells. Grow into haploid organisms by mitosis.
Topics To Know
1. Understand the purpose of meiosis
Meiosis provides Genetic variation:
- Depending on how chromosomes are lined up, 4 gametes get different
combinations of chromosomes.
- Genetic variation allows for the organism to adapt to the environment and
gives a better chance of survival, (Allows for organisms to be different)
2. What is crossing over and why is it important?
Crossing over is when homologous chromosomes exchnage portions of DNA (
chromatids) ; this is important as it allows for genetic variation.
3. Why does meiosis produce 4 different daughter cells?
Meiosis produce 4 different daughter cells to allow the gametes to have genetic
variation. These new combinations result from the exchange of DNA between
paired chromosomes.
4. Understand the difference between the stages of meiosis and mitosis
( next page)
5. What are traits and how are they important?
Traits are characteristics inherited from parent to offspring. They are
important as they play a role in determining an organism’s characteristics
and cell functions.
6. How does meiosis help in explaining the genetic diversity found in living
organisms?
Meiosis explains genetic variation found in living organisms by two processes:
Crossing Over: when homologous chromosomes exchange portions of DNA
- This allows for genetic variation by altering the original DNA and
changing it to a new form of DNA.
9. Know the stages of meiosis ( what happens in each stage and how to identify the
stages in an image)
Prophase I:
- Chromosomes begin to condense and pair up
- homologous chromosomes match up (synapsis)
- Crossing over in homologous pairs occurs
- Nuclear membrane disappears
- Spindle fibers appear( centrioles) & attach to
centromere of homologous chromosomes
Metaphase I:
- Spindle fiber attach to the centromere of
homologous chromosomes and moves them to the
middle of the cell.
- Independent assortment occurs in the randomness
of the order of chromosomes
Anaphase I:
- Homologus chromosomes separate and move to the
opposite poles
- sister chromatids stay together ( different from
mitosis)
Telophase I:
- 2 non-identical daughter cells are formed ( each
daughter has one chromosome of the homologous)
- nuclear membrane and nuclei form around
chromosomes
- Clevage furrow/cell plate forms
- DNA uncoils
Cytokinesis I:
- Cytoplasm splits
- Resulting in 2 ( SEPERATE) cells that must divide
again
Prophase II:
- Chromatin condenses to chromosomes
- Nuclear envelope dissolves
- Centrioles move to opposite poles and spindle fibers
form
Metaphase II:
- Chromosomes line up in the middle
- Meiotic spindle fibres at each pole of the cell attach to
each of the sister chromatids.
Anaphase II:
- Sister chromatids separate and move to opposite poles
