Biology Taxonomy and Classification

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Questions and Answers

What is the main purpose of taxonomy in biology?

To describe the physical appearance of organisms

To analyze the behavior of different animals

To classify and organize living organisms (correct)

To study the geographical distribution of species

Who is credited with developing the modern system of classification?

Gregor Mendel

Carl Linnaeus (correct)

Charles Darwin

Jean-Baptiste Lamarck

Which of the following best describes binomial nomenclature?

An ancient naming system used for extinct species

A system that categorizes organisms based on their habitat

A classification method focusing solely on physical traits

A two-term naming system for organisms (correct)

What do phylogenetic trees illustrate?

The evolutionary relationships among various organisms Signup and view all the answers

Which term refers to a scientist who studies taxonomy?

Taxonomist Signup and view all the answers

Which of the following is NOT a benefit of understanding phylogeny?

Understanding the reproductive cycles of organisms Signup and view all the answers

How many kingdoms of life are recognized in the six-kingdom system?

Six Signup and view all the answers

Which two components make up the scientific name in binomial nomenclature?

Species name and genus name Signup and view all the answers

What is the primary component that viruses consist of?

A core of nucleic acids and a protein coat Signup and view all the answers

Which of the following is true regarding viruses' signs of life?

Viruses exhibit no signs of life when isolated Signup and view all the answers

What type of cells do bacteriophages attack?

Bacterial cells Signup and view all the answers

In what form does viral genetic material exist?

Linear or circular form, not in a nucleus Signup and view all the answers

What process describes the immediate symptom-producing cycle of viral reproduction?

Lytic cycle Signup and view all the answers

What distinguishes the lytic cycle from the lysogenic cycle?

The timing of symptom appearance Signup and view all the answers

Which of the following best describes the nature of viral genomes?

Small, coding only for a few proteins Signup and view all the answers

What type of viral reproduction leads to a parasitic partnership with the host cell?

Lysogenic cycle Signup and view all the answers

What does the term biodiversity primarily refer to?

The variety of life forms and their interactions Signup and view all the answers

Why is genetic diversity crucial for a population?

It provides resistance to diseases and environmental changes. Signup and view all the answers

What happens to biodiversity when a keystone species is removed from an ecosystem?

The ecosystem may collapse or drastically change. Signup and view all the answers

Which of the following accurately describes ecosystem diversity?

The variety of habitats and ecological processes in an area. Signup and view all the answers

What would likely be a consequence of using broad-spectrum pesticides in agriculture?

Non-target species and overall biodiversity would decline. Signup and view all the answers

What is a primary advantage of species diversity?

It allows ecosystems to withstand environmental fluctuations. Signup and view all the answers

How many species have scientists identified, according to current estimates?

2 million Signup and view all the answers

What describes the interdependence of species in an ecosystem?

Species rely on each other for survival and stability. Signup and view all the answers

Which characteristic is true for organisms in Kingdom Protista?

They are eukaryotes. Signup and view all the answers

What distinguishes protozoans from algae within Kingdom Protista?

Protozoans ingest other organisms. Signup and view all the answers

What is a notable feature of slime molds?

They have a complex life cycle. Signup and view all the answers

What is the primary role of algae in aquatic ecosystems?

To serve as the main source of biological energy. Signup and view all the answers

Which of the following aptly describes the variability within Kingdom Protista?

Protists can obtain energy through different means. Signup and view all the answers

Which of the following statements about protists is accurate?

They do not have a consistent classification. Signup and view all the answers

How many species of protists have been identified to date?

Over 100,000 species. Signup and view all the answers

Which mode of locomotion is not associated with protists?

Wings. Signup and view all the answers

Which characteristic is used to classify animals based on their complexity?

Body structure Signup and view all the answers

What percentage of all animal species are vertebrates?

Less than 10% Signup and view all the answers

Which of the following is NOT a typical characteristic of animals?

Cell walls Signup and view all the answers

In animals with bilateral symmetry, what does cephalization involve?

Concentration of sensory organs at the body’s front end Signup and view all the answers

Which of the following types of body symmetry can divide an animal into two identical halves?

Bilateral Signup and view all the answers

What is primarily stored in the form of glycogen in animals?

Carbohydrates Signup and view all the answers

Which of the following best describes animals that exhibit radial symmetry?

They have a central point with body parts arranged around it. Signup and view all the answers

What type of tissues are responsible for movement and impulse conduction in animals?

Muscle and nervous Signup and view all the answers

Study Notes

Taxonomy

Science of classifying organisms
Two main purposes:
- To organize information about organisms
- To understand relationships between organisms
Taxonomists study this subject
Uses a system for classifying different organisms

Binomial Nomenclature

Two terms:
- Genus
- Species
Both terms are in Latin and genus name is capitalized

Taxonomic Levels (8 Taxa)

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

Phylogenetic Tree

The history of the evolution of organisms is called phylogeny.
Shows the evolutionary relationships among various biological organisms
Based on similarities and differences in their DNA and/or physical structures

Value of Phylogeny

Solving scientific and practical problems
Honeybees and pesticide resistance
Development of drugs
Saving endangered species

The Six Kingdoms of Life

Organisms in each kingdom are similar in their cellular structure, methods of obtaining nutrients, and metabolism

Biodiversity

Variety of life on Earth
Essential interdependence of all living things
Scientists have identified more than 2 million species, however tens of millions are not identified.
Complex interactions among all living things

Three Components of Biodiversity

Diversity of Genes
- Example: different breeds of dogs
- Genetic diversity is important because it allows populations to adapt to changing environments
- Advantages: Resistance to disease, pests, and environmental changes
Diversity of Species
- Example: Different types of trees in a forest
- Species diversity allows for ecosystem resilience
Diversity of Ecosystems
- Example: Different types of habitats in a region
- Ecosystem diversity allows for a wide range of resources and services

Keystone Species

Species that have a disproportionately large effect on their environment.
Removing a keystone species can have dramatic consequences for the ecosystem.

Viruses

Acellular particles
Found everywhere
Consists of a core of genetic material and a protein coat (capsid)
Can only reproduce within a host cell
Show a sign of life: Ability to reproduce
Attack bacteria (bacteriophages) or eukaryotes
Invade cells and use the host cell's machinery to synthesize more of their own macromolecules.

Viral Reproduction

Lytic Cycle: Immediate disease symptoms
- Attachment
- Entry
Lysogenic Cycle: Parasitic type of partnership with the cell

Viral Genome

Consists of either DNA or RNA not contained in a nucleus.
Can be single-stranded or double-stranded.
Can be linear or circular.
Very small = codes only for a few proteins

Kingdom Protista

Made up of algae, protozoans, slime molds
Eukaryotes and obtain energy in a variety of ways
Most are unicellular
Various modes of reproduction
Over 100,000 species identified
Most famous example: Amoeba

Protozoans

Some resemble animals
Ingestion of other organisms or absorption of nutrients from the environment
Others are photosynthetic
No cell wall
Modes of locomotion: cilia, flagella, pseudopodia
Some of the most common parasites in the world

Algae

Some resemble plants
Presence of chlorophyll
No roots, stems, leaves
Mainly unicellular
The source of biological energy - aquatic food webs
Biologists believe that plants evolved from green algae.

Slime Moulds

Some resemble fungi
Complex life cycle
Absorbing nutrients from the environment
Decomposers
Reproduce both sexually and asexually (spores, hyphae)

Animal Kingdom

Most diverse in appearances
Essential functions:
- Respiration
- Digestion
- Excretion
- Movement
- Reproduction
- Response to stimuli
Vertebrates make up less than 5% of all animal species.
95% of all animal species are invertebrates.

What is an Animal?

Multicellular
Heterotrophic
Eukaryotic
Store their energy reserves as glycogen
Animal cells lack cell walls
Reproduce sexually (most)
Two types of tissues responsible for impulse conduction and movement: nervous, muscle

Complexity and Advancement

Classified based on:
- Level of organization and specialization
- Body symmetry
- Germ layers

Body Symmetry

Radial symmetry
Bilateral symmetry

Cephalization

Concentration of sense organs and nervous tissue at the front end of the body.
Animals with bilateral symmetry usually display cephalization.

Body Cavity Formation

Most animals have a body cavity (coelom)
Fluid-filled space between the body wall and the digestive tract.

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Description

Explore the fascinating world of biological taxonomy, which involves the classification of organisms into various categories. This quiz covers key concepts such as binomial nomenclature, taxonomic levels, and the importance of phylogeny in understanding evolutionary relationships. Test your knowledge on how these classifications help address scientific challenges and protect endangered species.