Science 9: Biological Diversity BD1 & BD2 Vocabulary

Biological Diversity

The number and variety of organisms.

Species

A group of organisms with similar characteristics that are capable of interbreeding. The offspring have to be fertile offspring.

Variation

Any differences between living organisms caused either by genetic differences or environmental factors.

Intraspecies Variation

Variations between members of the same species.

Interspecies Variation

Variations among different species.

Natural Selection

The process by which favourable traits become more common in successive generations of a population, and unfavourable heritable traits become less common.

Structural Adaptation

A specific body part of an animal that helps an animal survive in its environment.

Behavioural Adaptation

Something an animal does to survive in its environment.

Niche

The role a species has in its environment, how it meets its needs, where it lives, and all interactions.

Specialist Species

Narrow niche, few food sources, live in small areas, do not tolerate changing conditions, intraspecies competition (some species), small populations

Generalist Species

Broad niche, eat a variety of foods, lives in many ares, tolerates changing conditions, interspecies competition (different species), larger populations

Dependency

When an organism needs to rely on something in order to survive.

Competition

Species competing for the same resources (food, space, water, sunlight, mates, etc).

Symbiosis

A close, long term relationship between species, based on dependency between organisms.

Commensalism

A relationship between two organisms where one organism benefits and the other organism is unaffected.

Mutualism

Two organisms working together in a way where both benefit from the relationship.

Parasitism

Involves one organism, a parasite, living off energy supplied by another organism, a host. Some parasites only attach themselves to feed while others are permanently attached. Some live attached to the outside of the host while others live inside of the host. The parasite benefits and the host is harmed.

Asexual Reproduction

The formation of a new individual from a single organism.

Sexual Reproduction

Creating a genetically unique offspring with 2 parents involved.

Clone

An identical copy of a molecule, gene, cell, or entire organism.

Binary Fission

Single cell organisms duplicates contents and divides, resulting in indentical daughter cells (Bacteria).

Budding

An asexual reproduction precess in which a bud forms on an organism, grows, and eventually breaks away to become a new organism independent of the plant (Hydra and Yeast).

Spores

A single-celled reproductive structure from which an individual offspring develops through mitosis (Plants, Algae, Fungi, etc.).

Vegetative Reproduction

Asexual reproduction in plants using meristems at the tips of roots and stems, which are rapidly reproducing cells (Cutting, Runners, Tubers).

Gametes

A reproductive cell (egg or sperm) containing half the number of chromosomes of a somatic cell.

Zygote

The new cell formed by the process of fertilization (Egg).

Ovule/egg

Ovule: The plant part that develops into a seed.
Egg: Female gamete, also a developing embryo enclosed in a shell or membrane and produced by animals that do not give birth to live young.

Sperm cells

Male gamete.

Fertilization

Female gamete (egg) and male gamete (sperm) combine to fertilize an egg/ovule.

Embryo

A multi-cellular organism during early development.

Pollination

After pollen reaches the pistil of a flower, the sperm nucleus travels down the pollen tube to fertilize the egg, then grows a zygote, to an embryo.

Heritable Characteristics

Passed from parent to offspring. (Hair Colour, Skin Colour, Freckle)

Non-heritable Characteristics

Not passed from parent to offspring. (Tattoos, scars, piercings)

Discrete Variation

There are a small number of variations (2-4). You cannot go in between categories. (Ability to roll tongue, blood types, sex)

Continuous Variation

There are many variations. (Eye colour, height, hair colour)

DNA (Deoxyribonucleic acid)

Molecular blueprint for living things, controls all the structures and functions of the cell, responsible for the variations between and among species

Genetic Code

Sequence of Nitrogen bases, controls production of proteins in cells

Nucleotide

A segment of DNA with one phosphate, one sugar, and a nitrogen base

Base pairs

A matching pair of nitrogen bases (adenine, thymine, guanine, cytosine)

Chromosomes

Tightly packed strands of DNA

Gene

A section of DNA that determines a specific characteristic or trait

Allele

Possible forms that a gene may take on (Black hair, tongue rolling)

Mitosis

Somatic cells (anything but gamete) have to be replaced very often, before dividing, a copy of each chromosome is made, new cell is genetically identical (same amount of chromosomes)

Meiosis

Forming new gametes by dividing cells, gametes only have 23 chromosomes

Somatic Cells

Any cell in your body that is not a gamete (sex cell)

Heritable Trait

A child receives at least one allele from each parent indicating what form of the trait the child will have

Dominant trait

The trait will always show up in the phenotype, even if only one copy is present, not always more frequent, is represented by a capital letter

Recessive Trait

The recessive trait will only show up in the phenotype if there are two copies (one from each parent)

Genotype

The genetic code for an individual’s traits (TT, tt, Tt)

Phenotype

The physical representation of the genotype (red hair, tongue rolling)

Purebred (Homozygous)

When there are two of the same version of the allele, either both dominant or both recessive

Hybrid (Heterozygous)

When there are two different versions of the allele, one dominant and one recessive

Co-domiance

Both parental traits are present in the phenotype, two versions of the same gene are expressed seperately to create a different trait

Incomplete dominance

An intermediate (mix) between the two parental traits

Chromosomal variation

Abnormalities in chromosomes when one is missing, extra, switched to another chromosome, or turned upside down, will result in disorders such as Down Syndrome

Punnett Square

A method to help figure out possible offspring combinations

GMO

Genetically modified organism that has altered genes to produce a new genotype