Bio 3

• Asexual reproduction


  Mode of reproduction that does not involve the use of gametes or sex cells
• Sporulation


  • Type of asexual reproduction where a new individual forms from an aggregation of cells surrounded by a resistant capsule or spore, which later on germinates
• Fragmentation


  • Type of asexual reproduction where the body breaks into two or more parts, with each fragment capable of becoming a complete individual
• Budding


  • Type of asexual reproduction where a new individual arises as an outgrowth (bud) from its parent, develops organs like those of the parent and then detaches itself
• Fission


  • Type of asexual reproduction involving the division of body into two or more equal parts
• Isogamy


  Fusion of similar gametes which are usually motile
• Heterogamy


  Fusion of dissimilar gametes. In oogamy, a large immotile gamete, the egg is fertilized by a small motile gamete, the sperm
• Bisexual reproduction


  Type of sexual reproduction involving the union of gametes from two genetically different parents
• Hermaphrodite


  An individual with both male and female reproductive tissues. In animals "self fertilization" is not common. In worms, a hermaphrodite needs a male to donate sperms in order to fertilize the oocytes in its body
• Differences between asexual and sexual reproduction


  • Number of parents involved
  • Gametes
  • Genetic composition of offspring
• Development


  1. Formation of sex cells

  2. Zygote formation

  3. Subsequent stages in one's life span

  4. Terminated by death
• Haploid (n) condition


  When a cell has only half the chromosome number or only one set of chromosomes
• Diploid (2n) condition


  When a cell has the full chromosome number or two sets of chromosomes
• Totipotent cell


  A cell that is capable of differentiating to become any kind of cell
• Gametogenesis


  Stage of development that yields haploid gametes
• Fertilization


  Stage of development that results in a unicellular diploid zygote
• Cleavage


  Stage of development involving a series of mitotic divisions to produce a multicellular blastula from a unicellular zygote
• Gastrulation


  Stage of development involving morphogenetic movements of the cells to produce a gastrula with distinct germ cell layers; in vertebrates, this will result in three layers: the outermost ectoderm; the inner endoderm, and the middle layer, the mesoderm
• Organogenesis


  Stage of development where the different germ layers differentiate into specific organ systems
• Growth


  Stage of development characterized by an increase in size of an individual
• Monozygotic twins


  Also known as identical twins; result from the union of a sperm and egg to form a single zygote that splits up during the first cleavage stage
• Dizygotic twins


  Also known as fraternal twins; results from the development of two or more separate fertilization events where the resulting zygotes develop almost simultaneously
• Testis


  Where sperms are produced
• Epididymis


  Where sperms are temporarily stored
• scrotum

  Supports the testis and epididymis
• vasdeferens here the sperm passes through from the testis before it joins the urethra

  Where the sperm passes through from the testis before it joins the urethrahere the sperm passes through from the testis before it joins the urethra
• Urethra


  Connected to the urethra and the urinary bladder, serves as passageway of both sperm and urine and terminates in the external urinary meatus of the penis
• Seminal vesicle


  Secretes fluid that forms part of the semen; secretion gives the semen its alkaline characteristic to counteract the acidity of the vaginal tract and therefore protect the sperm; the fluid also contains sugars like fructose
• Prostate gland


  Secretes fluid that also provides alkalinity to the semen; it also contains proteolytic enzymes, citric acid, phosphatases, and lipids
• Bulbourethral glands


  Paired glands that produce clear, viscous secretion known as pre-ejaculate that helps to lubricate the urethra for sperm to pass through, neutralizing traces of acidic urine in the urethra, and helps flush out any residual urine or foreign matter
• Clitoris


  The homologue (equivalent) of the penis in females
• Vagina


  Main entrance to the female reproductive tract, receives the penis during sexual intercourse
• Uterus


  Also known as the womb, where the embryo develops; with thick muscular walls, blood vessels: and the endometrial lining
• endometrium

  Innermost lining of the uterus where the embryo implants and develop
• Fallopian tubes


  Also known as oviducts; paired tubes that are connected to the uterus and terminate near the ovaries; this is where fertilization takes place
• Ovaries


  Female gonads that release the pocytes during ovulation, which are then caught by the fimbrae of the fallopian tubes in order for the oocytes to pass on to the fallopian tubes
• Morula


  A human blastula made up of a solid ball of cells
• Blastocyst


  A human blastula composed of the inner cell mass, which becomes the embryo, and the trophoectoderm, which becomes the placenta
• Implantation


  Process where the blastocyst implants itself in the endometrium; this signals the start of pregnancy
• Gestation


  Carrying of the embryo inside the female reproductive tract, specifically the uterus; can last up to 9 months in humans