Biology: Reproduction and Biodiversity

Biological Diversity

• Biological diversity relates to the number and variety of organisms.
• Different characteristics within species are variations.
• Variations can be environmental or genetic and are important for biological diversity.

Biodiversity Importance

• Biodiversity is critical for the survival of life on Earth.
• The removal of one species can collapse a food web.
• Medicines and food are sourced from plants, highlighting the importance of biodiversity.

Understanding Species

• Individuals of the same species can mate and produce fertile offspring.
• Lions and tigers are examples of distinct species
• Ligers are a fertile hybrid, whereas mules are not.

Classification

• Animals are classified and grouped based on common characteristics.
• Classification examples Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Carnivora, Family Ursidae, Genus Ursus, and Species Ursus arctos.

Speciation

• Speciation is the process by which new plant or animal species are created.
• Many animals share a common ancestor, over time they evolve into a separate species.
• Darwin's finches of the Galapagos are a famous example of speciation.

Variation Among Species

• Some species exhibit similar characteristics.
• Insects have 6 legs, while birds have feathers.
• Speciation leads to different species due to the evolution from a common ancestor based on environmental conditions.

Variations for Survival

• Adaptations enable organisms to survive and reproduce in their environment.
• Structural/Physical Adaptations; inherited physical characteristics that aid survival
• Behavioural Adaptations; learned or innate behaviours that aid survival

Value of Variation

• Areas with greater biodiversity can often tolerate changes in the environment.
• For instance, lodgepole pines are vulnerable to pine beetles, whereas forests with various trees are more resilient.

Measuring Biological Diversity

• A diversity index is a tool used to measure the amount of diversity in an area.
• It compares diversity of species to the total number of organisms.
• Areas with higher biodiversity tend to have healthier ecosystems.

Topic 1 Review

• Biological diversity, its importance, and its measurement through indexes.
• Variety within and among species, adaptations, and the critical relationship to survival.

Types of Data

• Discrete data consists of integers and countable, numerical values.
• Continuous data involves a range and measurable values, including fractions.
• Examples include height, weight difference, wind speed, volts etc.

Histograms vs. Bar Graphs

• Histograms display continuous data broken into ranges without spaces between bars.
• Bar graphs are used to display discrete data.
• Importantly bar graphs contain gaps between the bars.

Variation and Survival

• Variation extends beyond physical appearance, encompassing behavioral characteristics.
• Variations enable organisms to survive efficiently within ecosystems.

Niche

• Adaptations empower organisms to fulfill a specific role within ecosystems, helping them to compete for resources.
• A Niche is an organism's role in the ecosystem, encompassing where it lives and what it does.

Variation and Competition

• When resources are abundant, many species can share them.
• When one of those resources becomes scarce organisms will compete for it
• Competition occurs between members of the same species and/or members of different species.

Avoiding Competition

• Animals avoid competition by adapting behaviours like switching food preferences or hunting times.
• Warblers, which live across Canada and the US, avoid competition by eating insects and having different eating habits.

Broad Niche

• Canada has low biodiversity but supports large populations of individuals.
• A Broad Niche involves Roles/characteristics filled by a generalist organism.
• Generalist organisms have flexible requirements and can survive under variable conditions, relying on a variety of foods.

Narrow Niche

• Areas with relatively stable environmental conditions often support specialists.
• Narrow Niche; These organisms generally do not adapt well to environmental change.
• Specialization allows many species to inhabit a single area, but it prevents the individual species from spreading over a wide area.

Symbiosis

• Symbiosis is a type of interdependence between 2 species.
• Commensalism when one member benefits and the other neither benefits nor is harmed.
• Mutualism is where both members benefit.
• Parasitism when one member benefits and the other is harmed.

Topic 2 Review

• The meaning of niche, the differences in characteristics between generalists and specialists, and the pros and cons each.
• What symbiosis means, different types, and examples.

Traits are Passed On

• Characteristics are passed from parent to offspring, whether humans, plants, or bacteria.
• Heritable traits, characterized as those traits passed on from parent to offspring.

Reproductive Strategies

• Living organisms display various reproductive strategies.
• Asexual Reproduction: reproductive when one parent supplies genetic information, and the offspring has the exact same genetic information.
• Sexual Reproduction: reproduction occurs when two parents supply the genetic material for the offspring, which will not be exactly like either parent, rather it will be a new combination.

Asexual Reproduction

• This type of reproduction is common bacteria and fungi.
• No need for the organism to find a mate
• Reproduction can occur very quickly.
• Offspring in stable environments can survive and reproduce similar like their parents.

Types of Asexual Reproduction: Binary Fission

• This type of reproduction is used by a lot of unicellular, one cell, organisms.
• Binary Fission: a form of cell division when the cell duplicates its contents including its nucleus and organelles, then it will divide itself in 2.
• In binary fission, the split cells have a full copy of the genetic information.
• The offspring of binary fission will be identical.

Types of Asexual Reproduction: Asexual Spores

• Asexual Spores are a common fungi and mushroom reproduction
• Asexual spores take the form single-celled reproductive structures called spores, spores containing solely one parent's genetic material
• Asexual spores can produce many spores so that the odds are at least some of them will survive.

Asexual Reproduction in Plants

• Plants continue to grow throughout their lives.
• Asexual reproduction occurs in plants without the formation of special cells like spores.
• Plants produce a meristem, which can then specialize into roots/leaves/etc
• The meristem propagates new plants with cuttings, creating clones (exact copies) of the parent plant

Asexual Reproduction: Budding

• Budding is common in animals like sponges and hydra (very small), and yeast
• In budding, a bud forms, usually at the base of the organism. When the bud completely develops it will detach itself and becomes independent

Best of Both Worlds

• Bacteria can transfer genetic material directly from one cell to another, and is capable of reproducing sexually and asexually.
• Bacterial Conjugation is not reproduction since there are no new organisms.

Sexual Reproduction In Plants

• Angiosperms: flowering plants.
• Gymnosperms: plants that form seeds inside of cones.
• Fertilization occurs when egg and sperm cells (gametes) join to form a new cell, a zygote

Sexual Reproduction in Plants (Parts)

• Pistil: stigma, style, ovary, ovule.
• Stamen: anther, filament.

Sexual Reproduction in Plants (Functions)

• Pistil is the female reproductive part.
• Stamen is the male reproductive part.
• Pollen grains, containing a sperm nucleus, leave the anther, pollination occurs when reaching the pistil of a flower.
• Pistils grow a pollen tube allowing sperm to travel down and fertilize the egg. The zygote develops into a multicellular embryo.

Sexual Reproduction in Animals

• Both male & female gametes must arrive in the same place at the same time.
• Fertilization can occur outside or inside of the body.
• Specific conditions are required for the zygote to develop, nutrients and moisture, or warmth and protection.

Sexual Reproduction: Internal vs External

• Mammals are able to carry out internal fertilization.
• Internal Fertilization: High success rates for fertilization/reproductive success, egg is protected inside of the body, sperm deposited moves directly toward egg reducing risk to gametes
• External Fertilization: Low success rates for fertilization/reproductive success, male fish waits to spread sperm over eggs as female lays eggs to fertilize reducing risk by making lots of offspring

Topic 3 Review

• The definition of budding and binary fission,
• Organism examples that reproduce asexually versus sexually,
• The benefits and drawbacks of asexual and sexual reproduction, as well as both those of internal/external fertilization.

DNA

• DNA, or Deoxyribonucleic Acid, stores genetic information for heritable traits, directs structure/function of cells
• Chromosome is tightly packed strands of DNA that holds part part or all genetic information for cells; humans have 23 pairs of chromosomes.
• Gene: A section of DNA on a chromosome that codes for a specific proten and function.
• Allele: The variant of a gene that carry to dominant or recessive alleles
• Homozygoous: having two of the same allele of a gene, 2 dominant or two recessive.
• Heterozygous: Having one copy of each allele, 1 dominant or 1 recessive.
• Heredity, or genetics, passes characteristics and traits from parent to child, including hair color, eye size, or height.

Variation

• Discrete Variation: Traits with a limited number of possibilities, such as blood type, ear lobe attachment, or tongue rolling
• Continuous Variation: Traits with a a wider and larger range of possibilities, such as height, leaf length, or skin color.

Types of Traits

• A human will receive code in two copies per gene, one from each parent, coding for a specific set of traits.
• In some genes, traits will be dominant versus recessive, indicating the likelihood of the trait being passed on, with dominant traits being more common that recessive traits.
• Dominant Traits include dark hair over blonder hair, curly hair over straighter hair, baldness, widow’s peak hairline over regular hairline, and type A blood being dominant over type O blood.
• Recessive are traits that are unlikely to be passed on given dominant genes from other parent, for instance when type O blood that does not dominate any other blood types is passed.

Mutations

• Mutations are changes to genetic material, DNA, caused by mutagens, with possible harmful or beneficial effects.
• Radiation (X rays, UV, Cosmic rays) or carcinogenic materials (Tabasco, Asbestos, Formaldehyde, Alcohol, Radon, Benzene) are possible sources of mutations.
• Mutation examples; cystic fibrosis, sickle cells, Huntington’s, Turner syndrome, Klinefelter syndrome, or Cri Du Chat mutations, depending if mutation was chromosomal or at single-gene level.
• Body part mutation affects offsprings, versus mutations in gamete egg and sperm cells that affect offsprings.

Nature vs. Nurture

• Argument focuses on the question between characteristics from nature, and genetic, versus nurture and environment on individual genetics.
• Study identical twins separated at birth to see effects of both on genetically identical individuals.

DNA and Genetic Code

• DNA is in the shape of a coiled ladder shape called a double helix made of alternating sugars and phosphates.
• DNA has nitrogen base pairs of adenine and thymine, and guanine and cytosine, holding sequences of bases in a blueprint cell known as a gene.
• Body cells copy cells, then divided in a process known as 1 mitosis, creating a mother cell, cloning the data and the cell creating “daughter” cells with copies of genetic information. In human somatic cells, each has somatic pairs, genetic variation exists within and among traits of genes.

Sex Cells, Genetics and Genetic Engineering.

• Some genetic variations depend on sex/gamete cell type (Meisosis.)
• Genetic engineering then leads to more pieces of DNA from one cell or to the next, raising questions about the impact of nature. Moving human genes versus natural genes.
• • Biotech has developed the ability to move human genes (transgenic animals) for insulin producing to bacterial sources.
• Genetical modified traits that can be produced in large quantities. As well as “modified” forms of natural fishes, crops and animals that are part of common aquaculture today.

Domestication

• Over time through breeding positive qualities are paired together.
• Breeding in animal and crop raising have led to favourable traits, and has created unique breeds/hybrids from other breeds.
• Dairy animals are able to create higher milk production.
• Domestic animals are raised for meat and dairy production.

Selective Breeding

• Selective breeding allows you to bring positive qualities together.
• Selective breeding allows a wide range of genetic manipulation.

Theory of Natural Selection

• Charles Darwin’s observations and experiments have shown species traits passing down to offspring.
• Darwin explains that with more birth offsprings at a much faster rate that survival rate allows only the strong ones to reproduce, this is possible with gene variety among spices, which allows future population to change and genetic traits passing along, leading to survival.

Rate of Extinction

• Species are lost at alarming rates every year.
• Close to 70 species today.
• Biodiversity loss, as well as human impact has negative effects as the result of destruction, climate, and general overuse. and destruction of important natural resources.

Preservation of Biodiversity

• Some living organisms are indicators of particular environments and natural habitat.
• Some animals are indicators of certain environmental damage, and conditions within environment.

Roles of Zoos

• Sanctuaries allows animal populations to get protected by humans that can assist wildlife in need of resources, medical support, or gene diversity in mating.
• Zoos can have animals, plants, and seed-banks with rare species that they can assist in maintaining in population rates, or genetic variety.

Global treaties for global change

• Global treaties have drawn out of the desire to assist in the protection of animals, endangered ones primarily or plant species.
• Assist in the preservation of resources, prevent overuse and habitat destruction, and assist in the relocation and population management.

Explore asexual and sexual reproduction methods. Understand spores, budding, and plant propagation. Examine biodiversity's importance and the role of species in geographical isolation.