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BIO 100 General Biology > Unit 2: Ch 3, 5 > Flashcards

Unit 2: Ch 3, 5 Flashcards

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1
Q

Anaphase

A
  • 3rd phase of mitosis
    • Sister chromatids are cleaved apart by microtubules and become daughter chromosomes
    • Daughter chromosomes begin moving to opposite sides of the cell
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2
Q
A
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3
Q

Apoptosis

A

Programmed cell death

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4
Q

Are the daughter cells formed at the end of Telophase II diploid or haploid?

A

Haploid

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5
Q

Are the two daughter cells formed at the end of Telophase I diploid or haploid?

A

Haploid

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6
Q

Blastopore

A
  • Opening into the primitive gut formed at gastrulation
  • Becomes the anus
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7
Q

What happens during blastula embryonic formation?

A
  • Cells of the morula rearrange to form a hollow ball of cells
    • Creates 2 different areas:
      • Inner cell mass
      • Trophoblast
  • Blastula migrates into the uterus, where it burrows into the endometrial lining and latches on (implementation)
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8
Q

Blastula embryonic stage

A
  • 3rd embryonic development stage
    • Occurs ~ 5 days after fertilization
    • Occurs in oviduct, but ends in uterus
    • Creates hollow, fluid-filled ball of cells
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9
Q

Phases of the Cell Cycle

A
  1. Interphase
    1. G1
    2. S
    3. G2
  2. Mitosis
    1. Prophase
    2. Metaphase
    3. Anaphase
    4. Telophase
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10
Q

Cell development requirements

A
  • Cellular differentiation
    • When cells become specialized in structure and function
  • Morphogenesis
    • Produces the shape in tissues, organs, or the entire embryo during development
    • Process of pattern formation, which directs how tissues and organs are arranged in the body
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11
Q

Cell Division

A
  • Mitosis
    • Nuclear division
    • Parent nucleus produces two daughter nuclei, each having the same number and kinds of chromosomes as the parent nucleus
  • Cytokinesis
    • Division of the cytoplasm
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12
Q

Cell Theory

A
  • All organisms are made up of cells
  • Cells are capable of self-reproduction
  • Cells come only from preexisting cells
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13
Q

Types of Cells

A
  • Prokaryotic Cells (non-membranous):
    • Bacteria & Archaea domains
  • Eukaryotic Cells (membranous):
    • Eukarya domain
      • Protists
      • Animals
      • Fungi
      • Plants
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14
Q

Cellular Respiration

A
  • Occurs in both plant and animals
  • It is the process by which cells convert ADP into ATP
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15
Q

Cellular Respiration Formula

A

carbohydrate + oxygen →

carbon dioxide + water + energy

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16
Q

Centrioles

A
  • Occurs in the centrosome
  • Help organize a miotic spindle for chromosome movement during animal cell division
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17
Q

Centromere

A
  • The center of a chromosome
  • Where sister chromatids of a chromosome are held together
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18
Q

Cervix

A
  • Opening to uterus where sperm is deposited
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19
Q

Chloroplasts

A
  • Double-walled
  • Membrane-bound organelle in algae and plants with chlorophyll-containing membranous thylakoids
  • Where photosynthesis takes place
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20
Q

Chromatin

A
  • Contains DNA and proteins (histones)
  • Description
    • Loose, tangled, unorganized mass
    • Too small to be seen with the light microscope, need an electron microscope to view
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21
Q

Chromosome

A
  • Contains DNA and proteins (histones)
  • Description
    • Forms when the chromatin condenses into compact structures
    • Compact rod-like structure
    • Easily seen with a light microscope
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22
Q

Why do the cells at the end of Meiosis (I) not have the correct chromosome configuration?

A
  • The two haploid daughter cells have the incorrect chromosome configuration
  • Each chromosome should be made of only one chromatid
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23
Q

Cilia & Flagella

  • Composition
  • Function
A
  • Microtubules
  • Movement of cell
  • 9 + 2 pattern of microtubules
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24
Q

Cleavage stage of embryonic development

A
  • First stage of embryonic development
    • Occurs immediately after fertilization
    • Occurs in the oviduct
    • A series of rapid mitosis without an increase in the size of the cells
      • Increases the number of cells in the zygote
      • Cell division without cytoplasmic addition or enlargement
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25
Q

Cristae

A
  • The inner membrane of mitochondrion
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26
Q

Cytokinesis

A
  • May overlap with anaphase and telophase, but does not reach completion until just before the next interphase
  • Animal cells
    • Forms between the two daughter nuclei
    • Separates the cytoplasm to create two daughter cells
  • Plant cells
    • The rigid cell wall does not permit cytokinesis by furrowing
    • Involves building new cell walls between the daughter cells
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27
Q

Cytoplasm

A
  • The material inside the cell
  • 2 parts:
    • Cytosol: the fluid part; mostly water
    • Organelles: “little organs” inside the cell
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28
Q

Cytoskeleton

A
  • Forms the shape of a cell and the movement of its parts. Often compared with the bones and muscles of an animal
  • Non-membranous
  • Components
    • Microtubules
    • Intermediate filaments
    • Actin filaments
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29
Q

Differences between plant cells and animal cells

A
  • Plants
    • Have a cell wall located outside the membrane that is made of cellulose
    • Have chloroplasts
    • Have a large vacuole to store material
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30
Q

Diploid (2n)

A
  • The number of chromosomes, where two of each type of chromosome are present, in a species
    • Humans have 46 diploids (23 homologous pairs of chromosomes)
  • The correct diploid number is necessary for the correct function of an organism
  • Abbreviated 2n
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31
Q

DNA

  • Conformations
  • DNA Nucleotides
A
  • DNA is a nucleic acid polymer with 2 conformations
    • Chromatin
    • Chromosome
  • DNA nucleotides
    • Adenine
    • Thymine
    • Cytosine
    • Guanine
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32
Q

Does DNA replication take place in preparation for Meiosis I?

A

Yes

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33
Q

Does DNA replication take place in prior to Meiosis II?

A

No

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34
Q

Electron Microscope

A
  • Invented in 1950s
  • Magnifies 500k
  • The illumination source is electrons
  • Very expensive ($1M)
  • Cannot view living specimens. This is because the specimen is placed in a vacuum chamber
  • Can view thick or thin specimens
  • 2 types
    • Scanning electron microscope: used to view surfaces (such as the surface of a cell)
    • Transmission electron microscope: used to see inside an object (such as inside a cell)
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35
Q

Embryonic Development: 1st Week

A
  • Fertilization occurs
  • Cleavage begins
  • The morula is transformed into the blastocyst
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36
Q

Embryonic Development: 2nd Week

A
  • Embryo begins the process of implanting in the wall of the uterus
  • It is about the size of a period
  • The trophoblast begins to secrete the hormone human chorionic gonadotropin (HGP), which is the basis for the pregnancy test
  • Yolk sac/amniotic fluid forms
  • Gastrulation occurs
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37
Q

Embryonic Development: 3rd Week

A
  • Two important organ systems appear:
    • Nervous system
    • Heart
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38
Q

Embryonic Development: 4th & 5th Week

A
  • Body stalk connects the tail end of the embryo with the chorion
  • The umbilical cord is fully formed
  • Limb buds appear
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39
Q

Embryonic Development: 6th - 8th Week

A
  • The head achieves its normal relationship with the body as a neck region develops
  • All organ systems have been established
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40
Q

5 stages of embryonic development

A
  1. Cleavage
  2. Morula
  3. Blastula (blastocyst)
  4. Gastrula
  5. Neurula
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41
Q

Endoplasmic Reticulum (ER)

A
  • An interconnected system of membranous channels and sacs (flattened vesicles) that is physically continuous with the outer membrane of the nuclear envelope
  • 2 types:
    • Rough ER: Has ribosomes attached
    • Smooth ER: No ribosomes attached
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42
Q

Energy-Related Organelles

A
  • Chloroplasts use solar energy to synthesize carbs, which are broken down by the mitochondria to produce ATP molecules
  • When cells use ATP as an energy source, energy dissipates as heat
  • Nearly all organisms use the carbs produced by photosynthesizers as an energy source
  • Many organisms carry on cellular respiration
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43
Q

Epididymis

A
  • Location of sperm maturation in an adult human male
  • Sperm storage
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44
Q

Explain what is wrong with the chromosome configuration of the cells at the end of telophase I

A

The two haploid daughter cells have the incorrect chromosome configuration. Each chromosome should be made of only one chromatid

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45
Q

Explain why the cells at the end of Telophase II have the correct haploid configuration.

A

Daughter cells have the correct chromosome configuration because each chromosome is made of only one chromatid.

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46
Q

Fertilization Events

A
  • Sperm deposited at cervix
  • Sperm swim through the uterus to reach the oviduct
  • There are two oviducts, but oocyte is in one of them
  • Some sperm will find oocyte and squeeze through the corona radiata
  • Sperm must bind to the zona pellucida
  • Acrosome reaction occurs
  • Sperm binds to oocyte receptor
  • Membrane of sperm and egg cell fuse
  • Nucleus of the sperm enters the egg cell
  • Two nuclei fuse together, restoring the diploid chromosome number, and creating one zygote
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47
Q

2 events preventing the egg from being fertilized by more than one sperm

A
  1. Changes to the egg cell membrane
  2. Zona pellucida detaches from the egg and lifts off the egg, physically pushing the other sperm away from the egg
    • Exception:
      • If two sperm fuse with the egg cell at the EXACT same time (polyspermy)
      • Results in zygote having too many chromosomes
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48
Q

Follicles

A
  • Follicles are cavities in the ovary
    • Primary follicle: contains the primary oocyte; is the smallest follicle
    • Secondary follicle: contains the secondary oocyte; is bigger than primary because it fills with fluid
    • Graafian follicle: contains the secondary oocyte
      • The difference between secondary & Graafian follicle is just size
      • Graafian is larger
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49
Q

G0

A
  • Cells continue to perform normal processes, but no preparations are being made for cell division
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50
Q

G1

A
  • Cell cycle main checkpoint
    • Allows the cell to determine whether conditions are favorable to begin the cell cycle
    • Occurs before DNA replication
  • Organelles replicate
  • Some cells exit G1 to enter G0
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51
Q

G2

A
  • Checkpoint after DNA replication (S phase)
    • Cell cycle stops if the chromosomes are not going to be distributed accurately to the daughter cells
    • If DNA is damaged, this stage allows time for it to be repaired
  • Growth and final preparation for division
52
Q

Gamete cell

A
  • Cell used for reproduction
    • Oocyte: female gamete
    • Spermatocyte: male gamete
53
Q

Gastrula stage of embryonic development

A
  • 4th stage of embryonic development
    • Occurs ~ 7-10 days after fertilization
    • Occurs in uterus
    • Cells of the blastula rearrange
    • Rearrangement creates 3 regions of cells
      • Endoderm
      • Ectoderm
      • Mesoderm
    • Rearrangement “commits” the cells to form certain structures in the embryo (no longer capable of forming any cell type)
54
Q

Meiosis I events that ensure genetic variation in gamete cells

A
  • Crossing over
    • Non-sister chromatids exchange segments of DNA
  • Independent assortment at the metaphase plate
    • More than 1 way in which chromosomes can line up at the metaphase plate and separate
    • Many different combinations of chromosomes in the gamete cells
      • For humans: 223 = over 8M different combinations in the gamete cells
55
Q

Golgi Apparatus

A
  • Consists of a stack of between 3 and 20 slightly curved sacs whose appearance can be compared to a stack of pancakes
  • Referred to as the shipping center of the cell because it collects, sorts, packages, and distributes materials such as proteins and lipids
  • Forms the lysosome
56
Q

Haploid (n)

A
  • Cell condition in which only one of each type of chromosome is present
  • In humans, only sperm and eggs have the haploid number of chromosomes
57
Q

Homologous Chromosomes

A
  • Form during meiosis I
    • A set of 1 maternal and 1 paternal chromosome that pair up
    • They have the same genes in the same location where they provide points along each chromosome which enable a pair of chromosomes to align correctly with each other before separating during meiosis
58
Q

If a species has 14 pairs of homologous chromosomes, how many chromosomes would be present in a gamete cell from this species.

A

Fourteen pairs = 28 chromosomes total. A gamete has half that number which would be 14.

59
Q

Implantation

A
  • Blastula migrates into the uterus, where it burrows into the endometrial lining and latches on (implementation)
    • Occurs ~ 7 days after fertilization
    • Stays in the lining until development is completed
    • Burrowing can produce slight bleeding which can be incorrectly interpreted as a menstrual cycle
60
Q

Inner Cell Mass

A
  • Inner cell mass
    • Cells on the inner cell mass are called stem cells since they can form any cell in an organism
    • Form the organism
61
Q

Interkinesis

A
  • The period of time between meiosis I and meiosis II during which no DNA replication takes place
  • The daughter cells of meiosis I proceed directly into meiosis II
62
Q

Is a cell in Metaphase II diploid or haploid?

A

Haploid

63
Q

Is the mother cell diploid or haploid?

A

Diploid

64
Q

Light Microscope

A
  • Invented in 1600s
  • Magnifies 1000x
  • Illumination source is light
  • Features:
    • Can only view thin specimen
    • Can view dead or living specimens
    • Relatively inexpensive
65
Q

Lysosomes

A
  • Membrane-bound vesicles produced by the Golgi apparatus
  • Contain hydrolytic digestive enzymes and act as the garbage disposals of the cellular factory
66
Q

Meiosis

A
  • Occurs in any life cycle that involves sexual reproduction
  • Produces gamete cells
    • 2 rounds of nuclear division of 1 mother cell forming 4 haploid daughter cells (reduces the chromosome number from 2n to n)
    • Daughter cells are genetically identical to the parent
67
Q

Importance of Meiosis

A
  • Produces haploid cells that are genetically different than the original diploid parent cell
  • Important to the long-term survival of a species because it increases genetic variation within a population
68
Q

Meristematic tissue

A
  • Undifferentiated embryonic tissue in the active growth regions of plants
  • Plant tissue that retains the ability to divide throughout its life
69
Q

Metaphase

A
  • 2nd phase of mitosis
    • Fully formed mitotic spindle
    • Spindle fibers attach to the centromere of each sister chromatid
    • Asters develop to anchor assembly within the cell
    • Chromosomes are aligned at the metaphase plate
70
Q
A
71
Q

Microtubules

A
  • Helps maintain the shape of the cell and acts as tracks so that organelles can move
  • Organizing center is in the centrosome
72
Q

Mitochondria

A
  • Membrane-bound organelle in which ATP molecules are produced during the process of cellular respiration
    • The “power plant” of the cell
    • Contains its own DNA
    • Involved in cellular differentiation, cell death, and the aging process
73
Q

Mitosis

A
  • Nuclear cell division
  • Occurs when tissues grow or when repair occurs
  • Cannot be used to create gamete cells
  • At the completion, each of the chromosomes in the daughter cells consists of a single chromatid
  • Stages
    • Prophase
    • Metaphase
    • Anaphase
    • Telophase
74
Q

Mitosis & Meiosis Comparison

A
75
Q

Mitosis external controls

A
  • Density dependent inhibition: Cells will stop dividing when they physically touch another cell
  • Hormones: Communication chemicals. Hormones are how cells and organs communicate with each other. Some hormones tell a cell to divide by mitosis.
    • Ex: growth and sex hormones
  • Growth factors: Proteins secreted by a cell under specific circumstances. They tell the other cells immediately surrounding it to divide.
    • Ex: epidermal growth factor. It is secreted by injured cells to tell cells around it to divide so the injury can be healed. It is also naturally found in the saliva of animals and is why animals will lick their wounds. Doing so distributes the EGF to the cells
76
Q

Internal Controls of Mitosis

A
  • Proto-oncogene
    • Encode proteins that promote the cell cycle and prevent apoptosis
  • Growth factor
    • Hormones that deliver a signal to the plasma membrane of target cells
  • Tumor suppressor gene
    • Encode proteins that slow the cell cycle
77
Q

Frequency of Mitosis

A
  • Cells experience cell division at different times
    • Some don’t divide after birth (ie nerve cells & muscle cells enter G0)
    • Some lose the ability to do mitosis as they age (bones cells enter G0)
    • Some constantly perform mitosis (skin and blood cells)
78
Q

Mitosis in Plants

A
  • Same phases occur in plant cells as in animal cells
  • Plant cells have a centrosome and spindle, but they do not have centrioles or asters that form during cell division
79
Q

Morula stage in embryonic development

A
  • 2nd stage in embryonic development
    • Occurs 4 days after fertilization
    • Occurs in the oviduct
    • Due to cleavage, a solid ball of cells are formed
80
Q

Neurula stage of embryonic development

A
  • Stage 5 of embryonic development
    • Occurs ~ 1 month after fertilization
    • Occurs in uterus
  • Gastrula cells rearrange
  • Key formations:
    • Nervous system
    • Neural tube (neural tube becomes the spinal cord)
    • Notochord (vertebra)
    • Hollow regions: Gut & Coelom
81
Q

Non-disjunction

A
  • When chromosomes fail to separate properly during meiosis I or II
  • Creates gametes with an incorrect chromosome #
  • Results in chromosome disorders such as Down’s syndrome
  • Occurs most often in oogenesis, but can also occur in spermatogenesis
82
Q

Nuclear Envelope

A
  • Double layer membrane surrounding the nucleus
  • Separates the nucleus
  • Continuous with the ER
  • Has nuclear pores to permit the bidirectional transport of proteins and ribosomal subunits
83
Q

Nucleoli

  • Composition
  • Function
A
  • Concentrated area of chromatin, RNA, and proteins
  • Ribosomal subunit formation
84
Q

Nucleoplasm

A

Watery material inside the nucleus, containing chromatin

85
Q

Nucleus

  • Composition
  • Function
A
  • Membrane-bound organelle within a eukaryotic cell that contains chromosomes and controls the structure and function of the cell
    • Storage of genetic information
    • Synthesis of DNA and RNA
  • Structure
    • Nuclear envelope
    • Nucleoplasm
    • Nucleolus
86
Q

Oncogenes

A
  • Cancer-causing gene formed by a mutation in a proto-oncogene
  • Codes for proteins that stimulate the cell cycle and inhibit apoptosis
87
Q

Oocyte

A
  • Upon completion of meiosis, the oocyte becomes an egg
  • Oocyte types:
    • Primary oocyte: diploid mother cell that begins meiosis
    • Secondary oocyte: haploid daughter cell formed at the end of meiosis I
88
Q

Oogenesis

A
  • Following puberty and the initiation of the menstrual cycle, one primary oocyte begins to complete meiosis. It finishes the first meiotic division as two cells, each of which is haploid, although the chromosomes are still duplicating
89
Q

Oviduct

A

Tube connecting ovary and uterus.

Site of fertilization.

90
Q

Ovulation

A
  • Release of a secondary oocyte from Graafian follicle into the oviduct
  • Viable for 18-24 hours
91
Q

Peroxisomes

A
  • Membranous, enzyme-filled vesicle in which fatty acids and amino acids are metabolized to hydrogen peroxide that is broken down into harmless products
  • Contain an enzyme called catalase that breaks down H2O2 to water
92
Q

Photosynthesis Formula

A

Sunlight + CO2 + H2O →

Glucose + O2

93
Q

Plasma Membrane

A
  • Regulates the entrance and exit of molecules into and out of the cytoplasm
  • Phospholipid bilayer with embedded proteins
  • 2 regions
    • Intracellular region: inside the cell
    • Extracellular region: outside the cell
94
Q

Polar Body Oocyte

A
  • Nonfunctional product of oogenesis
  • Produced by the unequal division of cytoplasm in females during meiosis
  • In humans, 3 of the 4 cells produced by meiosis are polar bodies
95
Q

Polyspermy

A
  • When more than one sperm enters an oocyte
  • Results in the zygote having too many chromosomes, and development would be abnormal
96
Q

2 stages of prenatal development

A
  • Embryonic
    • An embryo from implantation to 3 months of development
    • Creates the pattern formations for organs to form
  • Fetal
    • 3 months from implantation to birth
    • Fetal development based on the pattern formation created to form the correct structure
97
Q

Primary and secondary spermatocytes

A
  • Primary: Consist of only one chromatid
  • Secondary: Duplicated and consist of two chromatids
98
Q

Prometaphase

A
  • Phase of cell division that occurs between prophase and metaphase
  • Characterized by attachment of the spindle fibers to the kinetochores of each sister chromatid
99
Q

Prophase

A
  • 1st phase of mitosis
    • Starts the process of nuclear division
    • Nuclear envelope begins to disintegrate
    • Spindle fibers begin to form
    • Chromatin condenses and the chromosomes are now visible
100
Q
A
101
Q

Function of Proteins

A
  • Regulate import and export of material
  • Communication between cells
  • Cell identification
    • Type of cell
    • Species
    • Individual within the species
102
Q

Proto-oncogenes

A
  • Gene that promotes the cell cycle and prevents apoptosis
  • May become an oncogene through mutation
  • Likened to the gas pedal of a car because they cause cells to continue through the cell cycle
103
Q

Ribosomes

A
  • Site of protein synthesis in a cell
  • Composed of proteins and ribosomal RNA
  • Smallest organelle in the cell. Can only be seen with the electron microscope
  • No membrane
104
Q

Rough ER

A
  • Studded with ribosomes on the side of the membrane that faces the cytoplasm
  • Modifies and processes newly made proteins
  • As proteins are synthesized on these ribosomes, they pass into the interior of the ER, where processing and modification begin
  • Proteins synthesized here are destined for the membrane of the cell or to be secreted from the cell
105
Q

Synthesis (S) Phase

A
  • DNA replication/duplication
  • At the beginning, each chromosome is composed of one chromatid
  • At the end, each chromosome consists of 2 sister chromatids that have identical DNA
106
Q

Secondary Oocytes

A
  • Receives almost all of the cytoplasm
  • If fertilized by a sperm, it completes meiosis II
    • Cytoplasm divides unequally
    • Forming an egg and a second polar body
  • The chromosomes of the egg and sperm nuclei then join to form the 2n zygote
  • If the secondary oocyte is not fertilized by a sperm, it disintegrates and passes out of the body with the menstrual flow
107
Q

Sister Chromatids

A
  • One of two genetically identical chromosomal units that are the result of DNA replication and are attached to each other at the centromere
108
Q

Smooth ER

A
  • Is continuous with rough ER but does not have attached ribosomes
  • Synthesizes the phospholipids found in cell membranes, as well as those that perform other functions
  • Stores calcium ions
  • Forms vesicles in which products are transported to the Golgi apparatus
109
Q

What is a somatic cell

A

Any non-gamete body cell

110
Q

Sperm

A
  • 3 parts to a sperm:
    • Head: Contains the haploid nucleus and is capped by a membrane-bound acrosome
    • Midpiece: Contains hundreds of mitochondria to produce the energy necessary to swim
    • Tail: a flagella used for swimming
  • ~100M released at the cervix, less than 10% reach the oocyte
  • The binding of sperm is specific
    • Prevents gametes of opposite species from fertilizing
    • Some exceptions
111
Q

Spermatogenesis

A
  • Production of sperm in males by the process of meiosis and maturation
112
Q

Suppose an error occurred in production of a sperm cell. Rather than having the correct haploid number of chromosomes which is 10, this sperm cell had 11. What would happen if this abnormal sperm cell fertilized a normal egg cell from this species?

A

It may be miscarried or develop a disorder.

The zygote would have an extra chromosome.

113
Q

Telophase

A
  • 4th phase of mitosis
    • Daughter chromosomes are at opposite sides of the cell
    • Cleavage furrow appears at the middle of the cell which will divide the cell in two
  • Many events in telophase are the “undoing” of prophase: spindle disappears, chromosomes de-condense to form chromatin, nucleus reforms, and centrosomes move next to the nucleus
  • Each daughter nucleus contains the same number and kinds of chromosomes as the original parental cell
114
Q

Testis

A
  • Site of spermatogenesis
  • Testes made of tubules are called seminiferous tubules
115
Q

Timing of Oogenesis

A
  • At birth: all primary oocytes are present in the ovary and have begun meiosis I, but paused in prophase I
  • At puberty until menopause: once a month, one primary oocyte completes meiosis I
    • Forms secondary oocyte
    • Begins meiosis II but pauses in prophase II
  • If fertilization occurs: secondary oocyte completes meiosis II to form the gamete
116
Q

Timing of spermatogenesis

A
  • At puberty until death
    • Primary spermatocytes are constantly formed from cells called a spermatogonium
    • Primary spermatocytes constantly undergo meiosis I and II to produce spermatocytes (sperm cells)
      • Rate of 300k sperm per minute or 40M per day
  • Notes
    • Unlimited number of gamete cells
    • There are no pauses in meisosis. Once it is started, it immediately finishes
117
Q

Trophoblast

A
  • Form embryonic structures that are not part of the organism (ie placenta and amniotic fluid)
  • Secretes HCG, which is detected by a urine pregnancy test
118
Q

Unequal cytokinesis

A
  • Takes place in oogenesis
    • Each time cytokinesis takes place, there is an unequal division of the cytoplasm
    • The large cell is the primary or secondary oocyte
    • The small cell is the polar body
      • The last polar body at the end of oogenesis is non-function (is not likely to be fertilized, and if it were, it would not develop into a viable zygote)
119
Q

Uterus

A

Site of embryonic and fetal development

120
Q

Vacuoles and Vesicles

A
  • Membranous sacs of various sizes
  • Storage of substances
121
Q

Vas deferens

A

Storage location for mature sperm before they pass into the ejaculatory duct

122
Q

What is the function of Meiosis?

A

Produce gamete cells

123
Q

When you were drawing each stage in Meiosis II there were two cells present. Why are there two cells in Meiosis II?

A

Because the sister chromatids within the two daughter cells separate and form four new haploid gametes.

124
Q

Why is mitosis important?

A

Without mitosis, cancer results

125
Q

Zygote

A
  • A diploid cell formed by the union of two gametes; the product of fertilization

BIO 100 General Biology (5 decks)

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