(Lesson-9)

• Life Strategy - refers to the behaviour, reproduction and growth pattern of an animal over time.
• R Strategies - tend to produce more, have shorter life span and reach maturity in a short period of time.
• K Strategies - Reproductions take more or longer time, have longer life span and reach maturity in a longer time.
• Semelparous - an organism that spend most of its life accumulating resource, preparing a single burst of reproductive output, then die shortly after.
• Iteroparous - an organism that undergo multiple reproductive cycles
• Spermatogenesis - formation of sperm cells
• Oogenesis - development of mature egg cells
• Anisogametic - the gametes are different in size
• Gametogenesis - formation/development of gametes through meosis: spermatogenesis/oogenesis
• Example of gonads

  • testes
  • ovary
• Two types of gametogenesis

  • Spermatogenesis
  • Oogenesis
• Two type of gametes

  • spermatozoa
  • ovum
• Vertebrates rely on hormones

  • progesterone
  • androgen
  • estrogen
• Steroid Hormones - regulator of animal production physiology
• Progesterone

  • produced from cholesterol in a number of steroidogenic
  • metabolized to androstenedione, exerting effect from both male and female
• Androgen

  • most common produce testosterone
• Estrogen

  • also produce in females, serves as the precursor/root for synthesis of this hormone
• Gonadotropins - control steroid hormone level
• Types of Gonadotropins

  (FSH) - follicle stimulating hormone

  (LH) - luteinizing hormone

  (CG) - chorionic hormone

  (GnRH) - gonadotropin-releasing hormone
• Two cells that control the spermatogenesis

  • Leydig Cells
  • Sertoni Cells
• Leydig Cells - found in the blood side of basal lumina, produce the testosterone that control spermatogenesis
• Sertoni Cells - are large cells that fills the gap between columns of spermatogenic cells, producing regulatory molecule, regulate testosterone-signaling pathway by producing an androgen-binding protein
• Estrous Cycle - reproductive behaviour of female mammals, closely linked to ovulatory cycle.
• Monoestrous - mammals differ in the number of training of estrous cycle
• Polyestrous - under go estrous cycle every year/end of the year, human and other primates are polyestrous animals, estrous cycle is commonly knowm as thr mestrual cycle.