Biology Final Exam Outline

 Monocots vs Dicots

Monocots: Seed leaves have ONE cotyledon, Leaf veins usually parallel, Stems vascular bundles in scattered arrangement, Pollen grain with ONE opening, Floral parts usually in multiples of THREE, Fibrous root systems. Dicots: Seed leaves have TWO cotyledons, Leaf veins usually branched, Stems vascular bundles arranged in a ring, pollen grain with THREE opening, Floral parts usually in multiples of FIVE, Taproot usually present.

Anatomy of an angiosperm

o Male and female flower parts

A. Sepals enclose and protect the flower bud B. Petals are often colorful and fragrant, may serve to advertise flower to insects and other pollinators C. Stamen (Male flower part) consists of a stalk tipped by anther, where meiosis occurs and pollen grains develop D. Carpel (Female flower part) with a long slender neck (style) with sticky stigma at tip, for pollen grains to stick.

Leaf Adaptions

1. Tendrils - For climbing 2. Spines - Defense and capturing water 3. Bracts - Attract pollinators

Life Cycle of a flowering plant

Embryo (Seed) -> Germinating Seed -> Seedling -> Mature plant with flowers, where fertilization occurs -> Fruit (mature ovary) containing seed

 Main components of Natural Selection

1) Variation—individuals vary in physical characteristics which can be passed on. 2) Competition— Limited availability of resources needed for survival. 3) Adaptation—individuals that are able to collect more resources are more likely to reproduce

The Environment Selects the BEST Traits

Darwin vs. Lamarck 

Lamarck believed organisms pass on traits they acquire during life, while Darwin believed natural selection acts on inherited variations already present in a population.

Evidence of Evolution as discussed in lecture

Fossils—one of the best sources of evidence for evolution. Transitional fossils—characteristics of two different groups. Fossils show things like how whales had terrestrial ancestors.

Case of Peppered Moth

Industrial revolution in England saw increase in pollution. Wild type was white-speckled. Melanistic mutation led to adaptation in changing environment

3 Mechanism for evolution other than natural selection

1. Genetic Drift - Changes in gene pool due to chance events (stochastic). 2. Gene Flow - Genetic exchange between populations. 3. Sexual Selection - Form of natural selection based on desirable traits in a mate (Intersexual and Intrasexual)

Formation of Species

Populations become isolated, then mutations create genetic variation, Natural selection acts on inherited traits, Population then becomes genetically different over generations, Reproductive isolation develops, New species are then formed. 

Sexual Selection as a form of natural selection

Form of natural selection based on desirable traits in a mate. Intersexual – generally males attracting females. Intrasexual – male to male competition for female

Biomagnification - DDT, Rat poison, bald eagles on Channel Islands

Toxins accumulate in progressively higher concentration up food chain. DDT - pesticide; caused thin eggshells in bald eagles. Rat Poison - accumulate in predators that eat poisoned rodents. Bald Eagles (Channel Islands) - harmed by biomagnified toxins, leading to reproductive problems. 

Complexity of food web

More species and feeding relationships = more stable ecosystem. If one species declines, other organisms can still find food. Complex food webs are more resistant to disturbances.

Topics in population Ecology 

Concerned with changes in population size and factors regulating populations over time. Studies: Size, Age Structure, Density, and Factors that influence changes in pop. size. Population growth is key component of research

Survivorship curves

o Type I vs Type III

Graph number of individuals alive at each age in maximum life span (Type I - most individuals die late in life) (Type III - most individuals die at a young age.)

Water and carbon cycles and how humans interfere

Humans interfere with Water cycle in three ways:

1. Taking water from aquifers. 2. Clearing vegetation from land and building roads and buildings 3. Interfering with natural processes that purify water and adding pollutants such as sewage and chemicals to water. Humans interfere with Carbon cycle: 1. Burning fossil fuels and destroying forests to make way for farmland and pasture. 2. Destroying forests reduces reservoir and loses organisms that take up excess CO2