Module 5 - IQ1

• Asexual reproduction


  offspring arise from a single organism, and inherit the genes of that parent only

  offspring are genetically identical to original parent.
• sexual reproduction


  combines the genetic information from two gametes

  involves gamete production -> fertilization -> differentiation -> growth
• Advantages of asexual reproduction

  Time Efficient; no need to search for mate, requires less energy
• Advantages of sexual reproduction

  genetic variation, long term evolutionary potential
• Disadvantages of asexual reproduction

  no genetic variation, population numbers difficult to control
• Disadvantages of sexual reproduction

  slower process, less population growth, requires long-term energy use
• 6 ways to asexually reproduce

  1. Binary fission

  2. Budding

  3. Fragmentation and regeneration

  4. Vegetation propegation

  5. Fungi - budding or producing spores

  6. Parthenogenisis
• Process of binary fission

  one prokaryotic cell divides into two

  
• Process of budding


  when a new individual develops on the side of the parent, can stay attached or fall off
• Process of fragmentation and regeneration

  when an organism is split and each part develops into a new individual by re-growing parts
• Process of vegetative propagation

  when a plants roots, runners, rhizomes, suckers, bulbs, corms or tubers are able to grow multiple plants that are genetically identical, even growing more parts so multiple ca grow (bulbs)
• Process that fungi use for reproduction


  by budding or producing spores

  Somatic cells in yeast form buds. During budding bulge forms on the side of the cell, the nucleus divides mitotically, and the bud ultimately detaches itself from the mother cell.

  Spores are produced by one parent only by mitosis so they are genetically identical to that parent.

  Spores allow fungi to expand their distribution and colonize new environments.
• What is Parthenogenesis


  parthenogenesis is the development of an egg into an embryo without fertilization ie. no males
• Where are gametes produced and by what process

  ovaries and testes via meiosis
• gametes are ...


  haploid (half the number of chromosomes - 23 in humans)
• zygotes are...


  diploid (46 chromosomes in humans)
• Define gamete


  a mature haploid male or female germ cell which is able to unite with another of the opposite sex in sexual reproduction to form a zygote.
• Define fertilization


  the action or process of fertilizing an egg, female animal, or plant, involving the fusion of male and female gametes to form a zygote.
• Define haploid


  describes a condition, a cell, or an organism that contains half of the set of homologous chromosomes present in the somatic cell
• Define diploid


  refers to the cell containing two sets of homologous chromosomes wherein each chromosome in a set is obtained from each of the two parent cells
• Define zygote


  fertilized egg cell that results from the union of a female gamete (egg, or ovum) with a male gamete (sperm)
• Define embryo


  an organism in early stages of development, before hatching from an egg or being born
• Mitosis - simple


  a process of cell duplication, or reproduction, during which one cell gives rise to two genetically identical daughter cells, often through splitting
• Meiosis - simple


  division of a germ cell involving two fissions of the nucleus and giving rise to four gametes, or sex cells, each possessing half the number of chromosomes of the original cell.
• What are flowing plants

  angiosperms
• Where are the reproductive centres of the plant?

  the flower
• What are the reproductive parts of plants

  
• What are the female parts of a plant

  Carpel (stigma, style, and ovary [and ovule])
• What are the male parts of a plant

  stamen (filament, anther)
• Function of the ovary and how its structure allows function


  Protects the ovules and seeds

  When turned into fruit, help with the dispersion of the seeds

  
  

  Enclosed structure allows for protection of the seeds

  Flesh tissue that develops in fruit attracts animals to eat it and its seeds
• Function of the ovule and how its structure allows function


  Develop embryos and contain and make the female reproductive cells

  
  

  Location at the bottom of the carpel allows for the embryos to be protected and the ovules to be fertilised
• Function of the stigma and how its structure allows function


  The stigma is a specially adapted portion of the pistil modified for the reception of pollen.

  The top of the female part of the flower which collects pollen grains

  
  

  Its structure relates to the fertilisation it relies on. If compact and sticky, it allows for pollinators to land on them and stick the pollen to them, not requiring a higher SA. If branched and elongated, it allows for pollen to more easily attach itself when blown by wind
• Function of the style and how its structure allows function

  Transports pollen from stigma to the ovary

  
  

  The style acts as a buffer against pollen contamination, since only compatible pollen is able to grow a pollen tube and travel through it

  It also transports only from the stigma
• Function of the anther and how its structure allows function

  Produces pollen for transportation, making it easier

  
  

  Allows for pollen to easily attach to pollinators or blow away

  Often attached to long filaments and being on the ends (often most exposed part)

  Numerous, so high change of reproducing
• Function of the filament and how its structure allows function

  Helps with the transportation of pollen

  
  

  Allows for the anther to extend as far as possible, therefore becoming more accessible for pollination
• Process of seed development

  1. pollination, the transfer of pollen

  2. pollen lands on the stigma

  3. a pollen tube grows from the pollen grain to an ovule.

  4. fertilisation. A nucleus then pass through the pollen tube and unites with the egg nucleus to produces a zygote.

  5. The zygote develops into a seed

  6. The ovule and ovary develop into a fruit around the zygote

  
• What is the difference between angiosperms and gymnosperms

  angiosperms develop in the ovaries of flowers and are surrounded by a protective fruit.

  
  

  gymnosperm seeds are usually formed in unisexual (all genders) cones, known as strobili, and the plants lack fruits and flowers.
• Sexual reproduction in gymnosperms


  -the cones of gymnosperms usually contain the gametophytes, the sporophyte is the rest of the plant.

  
  

  -inside the cones, male gametophytes are the pollen. Pollen holds the sperm cells

  
  

  -when pollen is carried by wind and lands on the female reproductive structure, it releases sperm and forms a zygote which becomes an embryo

  
  

  -sperm is transported through apollen tube

  
  

  -embryo encased with a supply of food becomes a seed

  
  

  -seed stays in female reproductive structure until mature, in which then it will travel to new areas if conditions are favourable
• Why is plant and animal sexual reproduction different?

  animals can move, plants can't (non-sessile and sessile)
• Define external fertilisation


  The uniting of sperm and egg outside of female body