Studied by 2 peopleReproduction
The process of producing an offspring
Offspring
The child of the parent
Sexual reproduction
The production of new organisms using two parents of different sexes
Zygote
A single cell that results from fertilization
Fertilization
The process of combining the egg cell and sperm cell
Sperm
A male sex cell
Egg
A female sex cell
Embryo
An unborn offspring that is under development
Asexual reproduction
The production of an offspring using only one parent
Fission
The original cell is copied and splits in half to form two genetically identical cells.
Ex. A bacteria divides and duplicates rapidly through fission.
Budding
A “bud”, grows and when it becomes large enough, it breaks off to form a new organism.
Ex. A small ocean organism forms a bud and the bud develops into a new small ocean organism and then it pops off.
Animal regeneration
An offspring grows from a piece of its parent.
Ex. a sea star’s leg falls off but the leg grows into a brand new sea star.
Vegetative propagation
When a part of a plant (root, stem, or leaf) grows into a brand new plant.
Ex. Strawberry plants send out “runners” that are long extensions of the roots and new strawberry plants start growing out of it.
Cloning
Humans produce identical individuals from a cell or from a cluster of cells taken from a multicellular organism.
Ex. New carrot plants can be produced from cells of a carrot root in a petri dish.
Advantages of sexual reproduction
Each offspring is unique
More genetic variation within a population
Diseases are less likely to affect individuals in a population
Population able to withstand changes to an environment
increased diversity
Disadvantages of sexual reproduction
Time & energy to find a mate is exhausting
Fewer offspring
Takes several months to develop offspring
Tends to require more parental care
Advantages of asexual reproduction
No need for a mate; one parent required
Takes less time; reproduction is very rapid
Less energy and stamina
Produces large numbers of offspring very quickly
Tends to require less parental care
Disadvantages of asexual reproduction
Very little genetic variation within a population; increased risk of extinction
Harmful mutations or diseases in parent will be passed down to all offspring
Entire population of genetically identical organisms can go extinct if there is a change in the environment.
Mitosis
One cell divides into two genetically identical daughter cells, that are also diploid cells.
Purpose of mitosis
to rebuild cells, such as skin cells, stomach cells etc.
diploid cells
A cell containing two sets of chromosomes
haploid cells
Cells containing only one set of chromosomes
Daughter cells
Cells that result from mitosis and meiosis
Meiosis
One diploid cell divides and makes four haploid cells.
Purpose of meiosis
To create sex cells which allows organisms to reproduce.
Prophase
Similar chromosomes from each parent pair up
Metaphase
Chromosomes line up in the center of the cell
Anaphase
Chromosomes are pulled to one side of the cell
Telophase
Nucleus reforms around the chromosomes and the cytoplasm and cell start to split
cytokinesis
The process of the cell beginning to split
Heredity
The passing of traits from parent to offspring
Dominant Traits
A trait that will appear in the offspring if one of the parent contributes it
Expressed when paired to a recessive trait
Recessive Traits
A trait that must be contributed by both parents in order to appear in the offspring
Only expressed when paired with another recessive trait
Alleles
The different forms of a gene
Ex. different eye color
Phenotype
How a trait is expressed
Ex. eye color, hair color
Genotype
The combination of alleles that control the phenotype
Ex. Bb, BB, bb
Homozygous
When the two alleles of a gene are the same
Ex. BB, bb, TT, tt
Heterozygous
When the two alleles of a gene are different
Ex. Bb, Tt
Homologous Pairs
Two chromosomes in a pair
Chromatids
One half of a duplicated chromosome
Locus
The location of a gene on a chromosome
Note 
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