Biological Diversity - Section 2 Flashcards
What are heritable traits?
Passed down from generation to generation
Examples: eye colour, hair type, skin colour
What is discrete variation?
Differences in characteristics that have defined form
Examples: either have blue eyes or not
What are continuous variations?
Differences in characteristics that have a range in form
Example: height
Variation caused by the interactions with the environment are ______ _________.
Not heritable
What is asexual reproduction?
Involves only one parent. All the resulting offspring are genetically identical to the parent
What are some examples of asexual reproduction?
Binary fission Budding Spore production Vegetable reproduction or propagation Regeneration
What is binary fission?
A cell splits exactly in half producing two identical individuals. This is how many one-celled organisms reproduce
What is budding?
The parent produces a small bud, or a smaller version of itself. The bud eventually pinched itself off the parent.
What is spore production?
Spores are similar to seeds, but are produced by the division of cells of the parent
What is vegetable reproduction/propagation?
The reproduction of a plant that does not involve the formation of a seed. Some plants will grow “runners”, others from tubers and bulbs, and many have roots that will form suckers
What is regeneration?
The process of an organism either regrowing a missing appendage, or growing a whole new organism from its own separated body parts
What is sexual reproduction?
Usually involves two parent organisms. This reproduction occurs in both animals and flowering plants, and results in offspring that are a unique genetic combination of characteristics from both parents
What are gametes?
Specialized cells involved in the process of sexual reproduction
What is a zygote cell?
The cell created by the joining of two gametes
The first cell of a new individual
What is the process called cleavage?
When the zygote divides into two cells
What is an embryo?
Continued division of the zygote forms a multicellular life formed called an embryo
What is sexual reproduction in plants?
Requires the joining of a male and female hamate to produce a zygote and an embryo
Most plants produce both male and female gametes
What is pollen in a plant?
Pollen contains the male gametes of a plant.
Pollen is found in the stamen, or male part of the plant
What are ovules in a plant?
Ovules contain the female gametes of a plant
Ovules are found in the pistil or female part of the plant
What is pollination?
Occurs when pollen is transferred from the anther of the stamen to the stigma of the pistil
What is fertilization?
Occurs when the male or female gametes unite
What is cross-pollination?
Occurs when the pollen of one plant is carried to the stigma of another by wind, water or animals.
What is cross-fertilization?
Occurs when a grain of pollen produces a long tube that eventually grows down the style into the ovary that contains the ovules.
What is an advantage of asexual reproduction?
Can produce lots of individuals very quickly
What is a disadvantage of asexual reproduction?
Produces no variation in heritable characteristics. Variation helps species survive the environment
What is an advantage of sexual reproduction?
Provides a lot of variation to help species survive environmental changes
What is a disadvantage of sexual reproduction?
Takes a lot of energy and only reproduces a limited number of offspring
