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UNIT 1
UNIT 2
UNIT 2
MIXED
100

Define biodiversity.

Variety of life at genetic, species, and ecosystem levels.


100

Define primary succession.

Community formation on bare surfaces with no soil. Starts with pioneer species (lichens)

100

Define diffusion.

Movement of particles high → low concentration across a semi permeable membrane (with the concentration gradient)

100

What is an enzyme

Biological catalyst that speeds up the rate of a reaction. Without being used up in the process

100

Which organelle is involved in photosynthesis?

Chloroplast

200

Difference between pioneer and climax species

Pioneer = fast-growing, tolerant; climax = stable, slow-growing, competitive.

200

What is a keystone species? Give an example.

Organism with significant impact on its ecosystem - Despite being small in abundance

200

Write the Word equation for respiration 

Glucose + oxygen → carbon dioxide + water + ATP.

200

What type of problem would a cell in a hypotonic solution face? Give an adaptation to combat this issue.

Water enters by osmosis Causing cell to lyse.

Adaptation = contractile vacuole

200

Explain the end result of succession.

Climax community

A stable community of k selected slow growing and long lived species

300

List the classification system in order

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species 

300

Explain how the structure of the chloroplast aids its function.                          

  • Green chlorophyll pigment on lamellae for Photosynthetic reactions
  • Flat lamellae (large Surface area to volume ratio) for light capturing
  • Stacked thylakoids give large surface area to volume ratio
300

Explain transpiration.

- Water evaporates out of tiny pores called stomata on plant’s leaves.

- Water moves from roots to leaves through the transpiration stream in the xylem.

- movement provides nutrients, water and support to the plant.

300

Compare the difference between light dependent and independent stage in chloroplast.

LD = thylakoid, reactant: water/sunlight, products: oxygen and H ions.

LI = stroma, reactant: CO2 and H ions, products: glucose & water

300

What is the difference between passive and active transport?

passive = no energy, with the gradient, high to low (osmosis, facilitated and simple diffusion)

active = needs ATP energy, against gradient, low to high, uses protein pumps or transport proteins 

400

Explain the importance of an apex predator in an ecosystem. Give an example.

Crucial to foodwebs as it is top of the food chain, Predators drive prey to adapt and vice versa ie evolutionary adaptations, Overpopulation of prey can effect geography of an ecosystem (e.g. Great white sharks)

400

What is the binomial naming system and why is it important?

Uses species & genus

reason: Communication – standardised method of naming organisms, Understanding evolution and biodiversity, Predicting relationships, Classifying newly discovered species

400

List 4 requirements for efficient gas exchange.

  • Moist
  • Large surface area to volume ratio
  • Thin – short diffusion distance
  • Maintaining a Concentration gradient
400

Explain the adaptations of a herbivorous digestive system.

dentition

long alimentary canal

4 chambered stomach

hind-gut fermenter

cellulase

400

Describe the process of eutrophication. 

Increased Nitrogen in water - Causes increase in algal growth - Algae covers water surface - Blocks sunlight - Restricted photosynthesis causes plant death - Causes anoxic conditions - Aquatic organisms die/suffocate

High death rate causes pungent odour

500

Explain and give examples of 3 types of symbiotic relationships.

  • Mutualism – both species benefit from the relationship eg clownfish and sea anemone
  • Parasitism – parasite benefits from the relationship and host is harmed eg. Cordyceps fungi and insect
  • Commensalism – one organism benefits, the other neither benefits nor is harmed eg barnacle and whale
500

Define competition and Explain the difference between intra specific and interspecific competition. Provide examples.

  • Organisms “fighting” for a resource that is in limited supply
  • Intraspecific  - between organisms of the same species,
  • e.g. male kangaroos fighting for a mate
  • Interspecific – between organisms of different species,
  • e.g. cockatoos and parrots fighting over nests in hollow trees
500

Draw a labelled diagram of the fluid mosaic model.

Diagram to include: 

Phosphate head (hydrophilic)

Lipid Legs (hydrophobic)

Protein channel

Intracellular space

Extracellular space

Glycoprotein Receptor

Phospholipid Bilayer

Carrier Protein

Cholesterol

Glycolipid

500

Give 5 factors that can affect rates of transpiration

Stomata closed when guard cells are flacid.

Temperature – high temperature increases the rate of transpiration

Wind – high wind speeds increases the rate of transpiration as evaporated water is blown away from the leaf

Less vapor around the leaf causes a gradient for evaporation.

Humidity – higher humidity decreases the rate of transpiration, less gradient for evaporation

Light – often light causes stomata to open allowing transpiration to occur.

500

Name and describe five different specialised cells and describe theirfunctions.

Chloroplast, RBCs, guard cells, mitochondria, nerve cells (neurons)