Biology

Question 1

What is classification?

Answer 1

Classification is the process of arranging similar things into groups.

It’s usually on the basis of similarities and differences in particular features (e.g. characteristics: a feature or quality of something).

Question 2

Who created the basis of the classification system that scientists use today?

Answer 2

The system is based on the classification method introduced in 1758 by Carolus Linnaeus, a Swedish botanist regarded as the founder of modern taxonomy.

Question 3

How have biological classifications have changed over time

Answer 3

Scientists use an internationally accepted system for classifying and naming organisms.

The system is based on the classification method introduced in 1758 by Carolus Linnaeus, a Swedish botanist regarded as the founder of modern taxonomy.

Over time, the Linnean classification system was expanded:
1. plants or animals.
2. first to three kingdoms and then to four

By the 1960s, scientists had organized living things into five kingdoms:
1. the Monera (bacteria),
2. Protista (protozoa and algae),
3. Fungi (mushrooms, yeasts, and moulds),
4. Plantae (plants),
5. Animalia (animals).

Carl Woese (1970s) reported on several key genetic differences he had observed in prokaryotes. Woese’s findings led scientists to split the Kingdom Monera into two kingdoms—the Bacteria and the Archaea. The six-kingdom system has been the standard used in taxonomy since the 1990s. Woese further proposed a major change in classification by placing all organisms into three domains—Eukarya, Bacteria, and Archaea—to reflect their three separate lines of evolution.

Question 4

Why is it important for scientists to use the same language of classification?

Answer 4

In science, it is important to be able to share and develop ideas with people all over the world. To do this, scientists across different fields need to create a universal language that everyone understands and agrees on.

Question 5

What are the scientific conventions for naming species?

Answer 5

Binomial nomenclature is a system of naming in which 2 names are used to identify an individual genus and species of an organism.

Scientists use Latin or Ancient Greek to name organisms.

“Genus species”

1. The first part of the name (genus) has a capital letter
2. The second part o the name (species) has a lower case letter

The Linnaean system assigns each species a two-part scientific name composed of Greek or Latin words. The

Question 6

Why do we refer to organisms by scientific names, not common names?

Answer 6

Using scientific names helps scientists avoid the confusion that can arise when referring to an organism by its common, or everyday, name.

For example, the name robin may refer to the European robin or to the American robin, or even to any of several other birds; however the robins’ scientific names—Erithacus rubecula and Turdus migratorius (European robin and American robin, respectively)—clearly identify the species being referenced.

The scientific names show that the birds are distinct species and verify that they are not closely related, since each belongs to a different genus.

Question 7

What are the 7 characteristics of living things?

Answer 7

MRS GREEN

1. MOVE by itself
2. RESPIRATE/breath in to make energy
3. SENSE/respond to environment
4. GROW
5. REPRODUCE
6. EXCRETE
7. NUTRITION

Question 8

How can you classify organisms?

Answer 8

You can classify organisms of an environment according to their position in a food chain.

Question 9

What is a dichotomous key?

Answer 9

A dichotomous key is a tool for scientists to identify an organism from a series of choices between 2 characteristics.

An organism will always be one or the other, but not both items in each level of the key (they are mutually exclusive, i.e. they are either in or out, yes or no).

Dichotomous = ‘to cut in two’.

Question 10

What are the reasons for classifying organisms?

Answer 10

The reasons for classifying include identification and communication.

1. Helps identify the relationships between organisms.
2. Clearly identify key characteristics of each organism.
3. Avoid Confusion.

Question 11

What are the 8 levels of the hierarchical system of classification?

Answer 11

Do Koalas Prefer Chocolate Or Fruit Generally Speaking?

DOMAIN (e.g. Bacteria, Archaea and Eukarya - animals, plants and fungi).

KINGDOM (e.g. plantae, fungi, animalia, bacteria, archaea, protista)

PHYLUM

Organisms are classified in a phylum or division based largely on general body plan.
E.g. Phylum Arthropoda: external skeletons, segmented bodies, and jointed legs (Insects, crabs, and arachnids).
E.g. Phylum Mollusca: A muscular foot and a soft unsegmented body that may or may not be covered with a shell (mussels, snails, and clams)
E.g. Phylum Chordata: internal skeleton and a backbone or notochord (a primitive backbone) (Fish, amphibians, reptiles, birds, and mammals including humans)

CLASS
E.g. Class Amphibia: moist, smooth skin and reproduce by laying large quantities of jellylike eggs in water (frogs, toads, salamanders)
E.g. Class Reptilia: reptiles have dry scaly skin and reproduce by laying small clutches of leathery eggs on land (snakes, lizards, turtles, tortoises)
E.g. Class Mammalia: feed milk to their young (reindeer, whales)

ORDER
E.g. Order Artiodactyla: cloven-hoofed mammals; cows, pigs, antelope, giraffes.
E.g. Order Cetacea: (whales, porpoises, dolphins).
E.g. Order Carnivora: (foxes, coyotes, lions, cats, otters, weasels)

FAMILY
E.g. family Canidae: (foxes, coyotes)
E.g. family Felidae: (Lions, cats)
E.g. family Mustelidae: (otters, weasels)

GENUS
E.g. genus Felis: (ocelots, domestic cats)
E.g. genus Panthera: (lions, tigers)
E.g. genus Lynx (lynx, bobcats)non.

SPECIES
Organisms are grouped into a species based on physical and genetic similarities. All members of a species have the same number of chromosomes.

The most important factor in species classification is the ability of members to successfully interbreed—that is, to mate and produce viable offspring (those that can in turn breed and produce more offspring.

Question 12

What are the kingdoms that contain single celled organisms?

Answer 12

1. Archaea (single celled, oldest form of life on Earth, used in treatment of sewerage, e.g. methanogen)
2. Bacteria (single celled, decomposes waste, some are harmful, e.g. penicillium)
3. Protista (single celled, e.g. algae)

Question 13

KINGDOM

Answer 13

1. PLANT
   Key features:
   - Multi-cellular
   - flowering plants
   - non-flowering plants
   compare the differences between flowering and non-flowering plants
   label the three divided parts of a plant
   plants are classified by the feature of carrying water (vascular or non-vascular)
   distinguish the similarities and differences between vascular and non-vascular plants
   - Vascular (roots and stems transport water around the plant)
   >Flowering,
   >non-flowering
   >ferns

• Non-vascular (don’t have specialised
  cells in their roots and stems to transport water and nutrients, reproduce using spores)
  >algae
  >moss

2. FUNGUS
   Key features:
   - uni cellular
   >yeasts
   > mushrooms,
   >moulds

• multicellular

3. ANIMAL
   Key features:
   - Multi-cellular
   - vertebrates
   > 1. fish
   > 2. amphibians
   > 3. reptiles
   > 4. birds
   > 5. mammals
   distinguish the similarities and differences between the 5 classes of vertebrates

compare the differences between invertebrates and vertebrates
- invertebrates
five groups vertebrates are divided into (fish, amphibians, reptiles, birds, mammals)

4. MONERA /bacteria (e.g. penicillium)
   Key features:
   - uni-cellular
5. PROTIST (e.g. protozoa and algae)
   Key features:
   - uni-cellular
6. Archaea (e.g. methanogen)
   Key features:
   - uni-cellular
   - oldest form of life on Earth
   - used in treatment of sewerage, e.g. methanogen

Question 14

What is the difference between invertebrates and vertebrates?

Question 15

What are the 7 classes of chordata?

Answer 15

1. Class Agnatha (Jawless fish)
2. Class Chondrichthyes (Cartilaginous fish)
3. Class Osteichthyes (Bony fish)
4. Class Amphibia (Amphibians)
5. Class Reptilia (Reptiles)
6. Class Aves (Birds)
7. Class Mammalia (Mammals)

Question 16

How can you identify organisms surveyed in a local habitat

Answer 16

Taxonomic identification
Data analysis

Question 17

What is the difference between a food chain and a food web?

Answer 17

A food chain outlines who eats whom.

A food web is all of the food chains in an ecosystem.

Each organism in an ecosystem occupies a specific position or level in the food chain or web.

Producers, who make their own food using photosynthesis or chemosynthesis, make up the bottom of the trophic pyramid.

TOP: Tertiary consumers
LEVEL 3: Secondary consumers
Level 2: Primary consumers
BOTTOM: Producers

Question 18

What are food chains?

Answer 18

Food chains are the sequence of transferring energy from organisms.

Food chains show feeding relationships in a habitat.

Key roles in the food chain; 1. producer
2. consumer
3. decomposer
key role: They break apart dead organisms into simpler inorganic materials, making nutrients available to primary producers.
importance: returning precious nutrients to the soil.
examples: mushrooms, worms, bacteria
4. predator

trophic levels. explain how energy is lost through each level in an energy pyramid

Question 19

What is a food web?

Answer 19

A food web is a network of food chains within an ecosystem.

I can create a food web using a series of food chains to connect between the organisms

I can label the key roles from a food chain within a food web

*
I can explain the impact on a food web when an organism is removed or added into the ecosystem
*
I can identify the affects the disruption to a food web can have on another organisms’ survival
*
I can list examples of food web disruption; fire, floods, agriculture, logging, mining, urbanisation etc.

Question 20

What is the role of microorganisms within food chains and food webs?

Answer 20

Bacteria and other microorganisms play an essential role in food chains and webs as Decomposers, acting at the end of the food chain.

Bacteria and other microorganisms break down energy-rich organic molecules.

These chemicals are found in dead plant debris such as leaves and animal excrement, and human remains.

Question 21

Describe the human impact on ecosystems.

Answer 21

Agriculture:
Habitat loss, especially removal of plants and trees which stabilize soil, increases erosion, and reduces the nutrient levels in terrestrial ecosystems. This, in turn, can decrease agricultural productivity. In turn, increasing erosion decreases water quality by increasing sediment and pollutants in rivers and streams.

Deforestation: Trees absorb and store carbon dioxide. If forests are cleared, or even disturbed, they release carbon dioxide and other greenhouse gases. Forest loss and damage is the cause of around 10% of global warming.

Fire by Aboriginal people: Aboriginal people have lived in Australia since time immemorial, and over time they used fire to manage the landscape. Small, controlled fires help them hunt, clear pathways through the land and regenerate vegetation. Bush fires were rare.

Palm oil: As well as widespread habitat loss for endangered species like Asian rhinos, elephants, tigers and orangutans, this can lead to significant soil erosion. It also produces greater human-wildlife conflict as large animals are squeezed out.

Cane toads: Cane toads are widely believed to kill many native animals, or to eat them, and so cause a major ecological catastrophe in the areas they invade.

Some of the community groups have suggested that toad invasion has incredibly serious effects on the native fauna.

Question 22

What is the difference between biotic and abiotic factors in an ecosystem?

Answer 22

Abiotic factors refer to non-living factors such as water and air. While there are living organisms in the air and water, neither water nor air can be classified as a living thing. The amount of precipitation in an ecosystem is another example of an abiotic factor.

Biotic factors are living things. For example, plants, animals, fungi, bacteria, and etc may all be components of your ecosystem and they are all living. They affect the environment in their own ways through interactions with other organisms and through their interactions with abiotic factors. For example, earthworms affect the soil, which is an abiotic component (if you don’t include the microorganisms living in the soil).

Question 23

What are the levels of organisation of an ecosystem?

Answer 23

1. organism
2. population
3. community
4. ecosystem
5. biosphere

Question 24

Describe 5 different species interactions in an ecosystem.

Question 25

How does energy flow through a food chain?

Answer 25

identify the different roles in a food chain and explain the transfer of energy between them

Question 26

What are the different types of biodiversity?

Answer 26

Biodiversity is usually explored at three levels:
1 genetic diversity
2. species diversity
3. ecosystem diversity

Question 27

What are the different categories of Biology?

Answer 27

Three major branches of biology are microbiology, zoology, and botany.

Microbiology is the study of microscopic organisms.

Zoology is the study of animals.

Botany is the study of plants.

Question 28

Define species

Answer 28

Species is defined as a group of organisms capable of interbreeding and creating fertile offspring. This means two organisms are the same species if they can have offspring and those offspring can also breed and produce offspring.

Question 29

Define taxonomy

Answer 29

Taxonomy is the science of finding, describing, naming and classifying organisms.

Taxonomy is used to identify species using names for each of the 7 (8) classifications.

Question 30

Compare how taxonomy is used to identify different species like humans and plants.

Answer 30

The distinction between the plant and animal kingdoms is based primarily on the sources of nutrition and the capability of locomotion or movement.

Question 31

Define exoskeleton.

Answer 31

a rigid external covering for the body in some invertebrate animals, especially arthropods

Question 32

Define endoskeleton.

Answer 32

an internal skeleton, such as the bony or cartilaginous skeleton of vertebrates

Question 33

Explain photosynthesis.

Answer 33

Photosynthesis is the process with how food chains are provided with energy from the Sun.

Question 34

Distinguish the differences between a herbivore, omnivore and carnivore

Answer 34

herbivore: eats plants
omnivore: eats plants and meat
carnivore: eats meat

Question 35

Introduced species

Answer 35

An introduced species are those that have been moved by humans to an environment where they didn’t occur naturally.

e.g. fox impact:
e.g. cane toad impact:
e.g. rabbit impact:

Question 36

Define endangered, vulnerable and rare species

Answer 36

Endangered:
Vulnerable:
Rare:

Question 37

Define biological control

Answer 37

biological control is a method of controlling unwanted pests.

e.g. Cactoblastis moth, rabbits, and cane toads

Question 38

define and explain how human activity has caused extinction