Bio Final Exam

Algae

Simple, photosynthetic organisms that live mostly in water and lack true plant structures.

Why algae lack roots/stems/leaves

Water supports them, allowing for direct nutrient absorption.

Algae unicellular or multicellular

Algae can be both unicellular and multicellular.

Three types of algae

The three main types of algae are green, brown, and red.

Where algae live in water

Algae mostly inhabit areas near the surface where sunlight is abundant.

Algal bloom

A rapid growth of algae often triggered by excess nutrients in the water.

Cause of algal blooms

Fertilizer and sewage runoff, particularly nitrogen and phosphorus, contribute to algal blooms.

Effect of algal blooms

Algal blooms can lead to oxygen depletion in water, creating dead zones where aquatic life cannot survive.

Red tide

A toxic algal bloom that can be harmful to marine life and humans.

Algae defense

Some algae produce chemical toxins to deter predators.

Lichen

A symbiotic relationship between algae and fungi, often found in various ecosystems.

Importance of lichens

Lichens play a crucial role in soil formation and have enabled life to move onto land.

First land plants

The earliest plants to colonize land were moss-like plants.

Why moss need water

Mosses require water because the sperm must swim for fertilization to occur.

Moss structures

Mosses have structures that are root-like, stem-like, and leaf-like, but they are not true roots, stems, or leaves.

Ferns advancement

Ferns are more advanced than mosses because they possess vascular tissue and true roots, stems, and leaves.

Fern reproduction

Ferns reproduce through spores.

Sporangia

Structures in ferns that produce spores.

Nonvascular plants

Mosses are classified as nonvascular plants due to their lack of vascular tissue.

Seedless vascular plants

Ferns fall under the category of seedless vascular plants.

Seeded plants

Plants that produce seeds are known as gymnosperms and angiosperms.

Gymnosperm reproduction

Gymnosperms reproduce through cones.

Male cone

The male cone produces pollen.

Female cone

The female cone contains ovules, which are the eggs.

Needle leaves

Needle-shaped leaves help gymnosperms reduce water loss.

Gymnosperm fertilization

In gymnosperms, pollen is carried by wind to fertilize ovules.

Angiosperm fertilization

Angiosperm fertilization involves pollination leading to fertilization within the ovary.

Flower function

The primary function of flowers is reproduction.

Pollinator advantage

Pollinators increase efficiency in reproduction and contribute to genetic diversity.

Population

A population is a group of individuals of the same species.

Community

A community consists of multiple populations of different species.

Ecosystem

An ecosystem includes a community of organisms and their physical environment.

Growth formula

The growth of a population can be calculated using the formula: (Births + Immigration) − (Deaths + Emigration).

J curve

The J curve represents exponential growth of a population.

S curve

The S curve indicates that growth slows as the population reaches the carrying capacity.

Carrying capacity

The carrying capacity is the maximum population size that the environment can sustainably support.

Limiting factors

Limiting factors include food, water, space, and disease, which can restrict population growth.

Human growth pre-1800s

Human population growth was slow prior to the 1800s.

Human growth post-1800s

Population growth accelerated rapidly after the 1800s.

Developed countries

Countries with low population growth often have high levels of development.

Developing countries

Countries experiencing high population growth rates are typically classified as developing.

Zero population growth

Zero population growth occurs at around two children per woman.

Fertility

Fertility refers to the average number of children born to a woman.

High fertility causes

High fertility rates may result from poverty, lack of education, and limited access to birth control.

Population pyramid wide base

A population pyramid with a wide base indicates a growing population.

Population pyramid narrow base

A narrow base in a population pyramid suggests a stable or declining population.

Habitat

A habitat is the natural environment where an organism lives.

Niche

A niche refers to the role and position a species has in its environment.

Niche overlap

Niche overlap occurs when two species compete for the same resources.

Mutualism

A mutualistic relationship benefits both species involved.

Parasitism

In parasitism, one organism benefits while the other is harmed.

Predation

Predation occurs when one organism kills and consumes another.

Competition

Competition happens when organisms vie for limited resources.

Internal parasite

An internal parasite lives within the host's body.

External parasite

An external parasite lives on the surface of the host.

Primary succession

Primary succession begins in lifeless areas, such as bare rock.

Secondary succession

Secondary succession occurs after a disturbance in an ecosystem.

Pioneer species

Pioneer species are the first organisms, such as lichens and mosses, to colonize barren environments.

Climax community

A climax community is a stable and mature ecosystem that undergoes little change.

Food chain

A food chain is a linear sequence of energy flow between organisms.

Food web

A food web consists of interconnected food chains within an ecosystem.

Producer

Producers are organisms, usually plants, that make their own food through photosynthesis.

Consumer

Consumers are organisms that obtain their energy by eating other organisms.

Decomposer

Decomposers break down dead organic matter and recycle nutrients back into the ecosystem.

Herbivore

Herbivores are animals that primarily consume plants.

Carnivore

Carnivores are animals that primarily eat other animals.

Omnivore

Omnivores eat both plants and animals.

Detritivore

Detritivores feed on dead organic material.

Energy pyramid

An energy pyramid illustrates the energy loss that occurs at each trophic level.

Biomass pyramid

A biomass pyramid displays the total mass of organisms at each trophic level.

10% rule

The 10% rule states that approximately 10% of energy is transferred from one trophic level to the next.

Biomagnification

Biomagnification refers to the process where toxins accumulate at higher trophic levels.

Most affected by biomagnification

Top predators are typically the most affected by biomagnification.