Cells as the Basis of Life(Module 1) Define Example Different Type of Cells

Eukaryotic Eukaryotic cells are cells that contain a nucleus. They are usually larger than prokaryotic cells, and they are found mainly in multicellular organisms. Organisms with eukaryotic cells are called eukaryotes. Eukaryotic cells also contain other organelles besides the nucleus. An organelle is a structure within the cytoplasm that performs a specific job in the cell. Ribosomes, the organelle where proteins are made, are the only organelles in prokaryotic cells.

Prokaryotic -It’s cells without a nucleus. The DNA in prokaryotic cells is in the cytoplasm rather than enclosed within a nuclear membrane. -It is found in single-celled organisms, such as bacteria. Organisms with prokaryotic cells are called prokaryotes. They were the first type of organisms to evolve and are still the most common organisms today

Cell Structures

The Nucleus Description- large, has a double layer of membrane Function- contains the nucleolus, genetic materials and cellular activities

Mitochondria Description- small,

made of two membranes and a matrix (gel-like substance) Function- is the energy house of the cell as it stores and produces energy (cellular respiration)

E.R

-Rough E.R Description- rough-

looking, covered with ribosomes, sheets of bumpy membranes Function- follows instructions from nucleus to make proteins the cell needs (has ribosomes attached to it)

-Smooth E.R Description- tube-like structure Function- transports material through cell, digests lipids and membrane proteins

Ribosomes Description- It is composed of two subunits, large and small. They each consist of ribosomal RNA and proteins. Function- it makes / produces protein and is attached to the rough endoplasmic reticulum

Golgi Body Description- flattened

stacks of membrane bound sacs Function- modify proteins made by the cell and pack and export proteins to the cell parts

Lysosomes Description- single outer membrane, contains many enzymes Function- breaks down the waste products and detoxifies the cell

Chloroplasts Description- green,

oval-shaped, contains chlorophyll Function- where photosynthesis takes place

Structure of Membranes

Description- a delicate structure Function- controls the movement of substances in and out of the cell

Cell Function Diffusion -The movement of any

type of molecule from an area of high

concentration to an area of high concentration to an area of low concentration, until equilibrium is reached. (passive)

Osmosis -The movement of water molecules from an area of high concentration of water to an area of low concentration of water, through a semipermeable membrane. (passive)

Active Transport -The movement of molecules against their concentration gradient from an area of low concentration to high concentration through a semipermeable membrane. -Uses energy.

Endocytosis -Moving substances into cells -phagocytosis (solids) -pinocytosis (liquids)

Exocytosis -Removing substances from cells.

Importance of SA/Vol

-The larger SA:V the faster the reaction/diffusion.

Photosynthesis -It create food for the cells

Carbon Dioxide + water --> chlorophyll/ sunlight --> glucose + oxygen

Cellular Respiration - -It create energy for the cell

Anaerobic -Type of respiration through which cells can break down sugars to generate energy in the absence of oxygen.

Fermentation

Aerobic -Type of respiration that relies on oxygen to produce energy.

Glucose + oxygen --> carbon dioxide + water + ATP energy

What cells need

What cells need to get rid

Enzymes

-Properties -It decrease activation energy barrier in order to speed up the reaction.

-Effect of temperature

-As the temperature gets hotter, enzyme work faster. -Extreme high temperature enzymes breaks down that cause them to not work. -They don’t denature.

-Effect of PH -The enzyme is denatured. -Extremely high or low pH values generally result in complete loss of activity for most enzymes. -pH is also a factor in the stability of enzymes.

Organisation of Living Things(Module 2) Define Example Organisation of Cells Unicellular -Act individually and

independently. -Have ‘generalised’ cells. -Small size means cell requirements and wastes can move easily by diffusion, osmosis or active transport. -Mostly aquatic or live in damp places

-Cyanobacteria -Yeast -Paramecium

Colonial -Slightly specialised cells that are connected or loosely aggregated -Cells are in organised structures that work together to meet the needs of other cells in the organism -Many colonial organisms are aquatic and sessile (can’t move) so they rely on filter feeding and stinging for nutrition -Mostly aquatic

-Coral -Sponge

Multicellular life-form Multicellular -Plants

-Animals -Most Fungi

-Differential cells -The smallest unit of life. -They perform specific functions

Muscle cell - its job is to contract or relax.

-Tissue -Groups of cells with similar functions. ~They perform functions as a group of cells

Muscle tissue - made up of muscle cells, job is to contract or relax .

-Organs ~Made up of groups of tissues that function as a whole

The stomach - made of muscle tissues, is moved to churn food .

-Systems -Groups of organs that function together as a coordinated system to perform a role for the body.

Digestive system - made up of organs such as the stomach.

-Why this works Structure &Function in Plants

Leaf -Structure -Guard cell opens which lets

water out and CO2 in via the stomata -CO2 continues to move up through the spongey mesophyll and palisade mesophyll -Oxygen leaves out of the stomata and into the atmosphere -Guard cell closes when water has been lost

-Function -Absorb light -Where photosynthesis and gas exchange occurs -Control water levels

Stomata -Allow intake of CO2 -Prevent water loss -When guard cell is full of water they open and intake gas. When water is lost they close

Photosynthesis Vascular system -Plant vascular systems provide

support as well as transport - Plant energy and nutrient requirements are low so no internal pump is needed -Animal vascular system is able to fight pathogens -Animals need a heart -Both plant and animal vascular systems regulate temperature

-Xylem -Most xylem tissue is made up of dead cells and xylem vessels,

Transports water and mineral upward in a passive transport

which have walls strengthened with lignin that prevent them from collapsing -Consists of Xylem tracheids and Xylem Vessels

-Phloem -Transports sugars from the leaves to other parts of the plant for use or storage -Made up of living cells, sieve tube cells and companion cells that is thin cellulose

Transports sugars and water in any direction in active transport

Phloem Xylem

Function Transportsugars Transportwaterandminerals

Movement Upordown(sourcetosink) Uponly

Structure Thinwalled.Containsieveplatesandcompanioncells Thickligninwalls.Continuous

Nature Livingtissue Deadtissue Location Outersideofvascularbundle Centreofvascularbundle Gas exchange Comparison; what they need -Autotrophs -Require gases, simple nutrients

and ions, and water

-Heterotrophs - Require gases complex molecules and water

AUTOTROPH Autotrophs are organisms that create/make their own food. In terms of nutrients, they require carbon dioxide, sunlight and water to perform photosynthesis as well as oxygen and sugar to perform respiration. Macroscopic Something that can be seen with the naked eye Microscopic Something that is so small that it can only be seen with the aid of a microscopic Identify Characteristic Results Leaf Macroscopic Leaf is a plant

organ -Each leaf has multiple layers including; -mesophyll which contains cells with high numbers of chloroplast

-The high chloroplast concentration the leaf is the primary plant organ involved in photosynthesis

Microscopic Stomate is an opening in a leaf surface

~Each stomate is surrounded by 2 guard cells which can expand and contract, changing the size of the opening.

~The plant can control the loss of water through transpiration

Stem Macroscopic Stem is a plant

organ connecting the roots and leaves

~The stem contains vascular tissue for example; xylem and phloem

~The plant is able to move water and dissolved substances from the roots upwards in the xylem, such as products of photosynthesis, around the plant to where they are required through the phloem

Microscopic Vascular bundles are a collection of vessels in vascular plants

~The xylem are dead, hollow vessels, strengthened with lignin. In contrast, the phloem are living tissue, containing sieve plates and associated companion cells.

~The xylem are able to transport water and dissolved substances up only through the transpiration stream and cohesive and adhesive forces. ~The phloem move sugars, produced during photosynthesis, from source (leaf) to sink (anywhere required).

Flower Macroscopic Flower is the

reproductive organ of the plant

Each flower consists of -Female components; the pistil (stigma, style, ovary) -Male components; the stamen (anther and filament)

~Pollination occurs when pollen from the male anther is transferred to the female stigma

Microscopic Filament and anther are the male reproductive structure of a flower, collectively called the stamen

~The filament is a long slender structure that supports the anther, an oval shaped structure, which is where pollen develops

~These structures, the pollen is exposed to pollinators such as insects, birds or wind

Roots Macroscopic & Microscopic

Roots are an organ system in plants

~The main root of a plants is called the primary root while the others are called secondary roots. Within each root there is vascular tissue (xylem & phloem) connecting the roots with rest of the plant. ~Root hairs are elongated microscopic outgrowths from the outer layer of cells in a root.

~These structures, the root hairs significantly increase the surface area over which water and dissolved nutrients can enter the plant.

Digestion in a Mammal Physical Digestion -Occurs when food is made into

smaller pieces by the action of teeth and the

muscular churning

of the stomach. -Increases the surface area of food for chemical digestion

Chemical Digestion -Uses digestive enzymes -Saliva contains enzymes that begin chemical digestion in the mouth -Proteins are broken into amino acids

Types of Enzymes -Amylases Acts on Carbohydrates -Potato -Proteases Acts on Proteins -Lipases Acts on Fats Absorption Elimination -Undigested food moves to the

rectum at the end of the large intestine which stores faeces. ~The anal sphincter controls storage until it’s eliminated by the body

Gas Exchange in Animals Surface ~Large surface area relative to

the volume of the organism ~Thin to minimise diffusion pathway (distance) ~Moist as gases can only cross cell membranes when they are dissolved in aqueous solution. ~Close contact with blood supply

-In Insects ~Insects breathe through spiracles (small holes). ~Oxygen enters the spiracle and travels along a network of tubes called trachae which divide further into tracheoles. ~The tracheoles divided until their microscopic ends penetrate into individual body cells. ~Spiracles can be opened and closed to prevent water loss and opened when greater respiration is needed. Waste carbon dioxide also exits the spiracles.

-In Fish ~A fish breathes by taking water into its mouth and forcing it out through the gill passages. ~As water passes through the lamellae of the gills dissolved oxygen diffuses from the water into the blood. ~Gills have rich supply of blood vessels. ~Carbon dioxide from the blood diffuses out of the gills in to the water at the same point.

-In Amphibians ~Most breathe through their skin and to a lesser amount their lungs (there are exceptions). ~The skin absorbs oxygen, which is captured by capillaries lying just beneath the skin's surface. At the same time carbon dioxide diffuses from the capillaries out through the skin. ~The skin must stay moist for the cutaneous gas exchange to work properly

Advantages of internal gas exchange (Mammals)

~Reduces water loss and maintains a moist gas exchange surface. ~This allows mammals to inhabit a greater variety of terrestrial habitats. ~A transport system (blood vessels) reduces the distance dissolved gasses have to diffuse. ~This also enables mammals to grow to larger sizes than many other animal groups.

Internal Transport in Animals

What is carried in blood Blood Cells Veins -Carries blood from the body,

except the lungs

Arteries -Carry blood away from the heart

Capillaries -Passes oxygenated blood into tissues and receives CO2

Heart -Function ~Gases are exchanged in the

lungs. the oxygen travels down all the way through the bronchioles to smaller tubes,

increasing the surface area more and more until it reaches the alveoli, the air sacs.

-Structure Changes in blood during circulation

Open circulatory system -Heart pumps blood into body cavity -Blood is in direct contact with tissue cells -Pressure of blood is low -Blood returns to the heart slowly -Disadvantage; Oxygenated blood mixes with deoxygenated blood

-Insects -Crustaceans -Spiders

Closed Circulatory Systems -Heart pumps blood to blood vessels -Blood doesn’t come into direct contact with tissue cells -Pressure of blood is high -Blood returns to the heart quickly -Disadvantage; Pumping requires great pressure

-Birds -Fish -Amphibians -Reptiles -Mammals

Tracing the products of photosynthesis Indicates Source of Oxygen Water is the source of oxygen

-Released during photosynthesis Source of Carbon Carbon dioxide is the source of carbon

-The glucose produced during photosynthesis

Tracing movement of Glucose Glucose produced in the leaves is transported to all parts of the plant.

Transpiration-cohesion-tension theory The movement of water upwards in a plant and evaporate into the air, even against the force of gravity Transpiration-cohesion-tension theory (steps) ~Water moves into the roots through osmosis ~Water evaporates from the plant via transpiration ~As a result of cohesive and adhesive forces water molecules are drawn up the xylem Translocation (source-to-sink) Translocation is the movement of sugars (produced during photosynthesis) from leaves to other tissues throughout the plant. Also referred to as the source-to-sink model. The leaves are the ‘source’ of the sugars and the destination of the sugars are the ‘sink’.

Translocation theory ~Active transport of sugars from photosynthetic cells into phloem ~Osmosis of water from xylem into phloem ~Flow of sugar in all directions around plant ~ Active transport of sugars into non-photosynthetic cells Hypothesis Conclusion Joseph Priestly (1733-1804) A plant ‘restores’ the air for

breathing animals. The plant ‘restores’ the air that the breathing animals and candles remove. - Confirmed that gas exchange was occurring where plants produced a gas (oxygen) that supported burning and was essential for the survival of animals.

Nicolas de Saussure (1767-1845)

Plant growth requires both H2O and CO2.

Demonstrated plant growth required both H2O and CO2

Melvin Calvin (1911-1997)

Photosynthesis consists of a series of reactions

Carbon fixation -> Reduction of GP -> Regeneration of RuBP

Biological Diversity(Module 3) Define Example Evidence for Evolution Biochemistry ~Chemistry that deals with

chemical compounds and processes occurring in living things

Biochemistry evidence -DNA (DNA hybridisation) ~Method; hybridising

~It measures the degree of genetic similarity between pools of DNA sequences. ~It is usually used to determine the genetic distance between two organisms.

Biogeography ~The distribution of species which share a common ancestor, correlates fairly well, with the distribution of continents throughout geologic history.

Comparative anatomy -Homology ~Structures are the same in

different organisms but serve a different purpose in each

-Arm of a human, wing of bird or bat, and leg of a dog

-Analogy(analogous structures)

~Similar structures that evolved independently in two living

-Wings of bats, birds and insects -Fins of penguins and fish

organisms to serve the same purpose.

-Vestigial structures ~No longer has a purpose in the current form of a species, but did in its ancestor ~It have been reduced in size, and are only partially formed, but their existence is very strong evidence that the species is descended from an ancestor that needed that feature

-Human appendix -Pelvic bone of a snake -Wings of flightless birds.

Modern-Day example Cane toads and crocodile ~Cane toads are poisonous and

kill Australian freshwater crocodiles in the Northern Territory. Freshwater crocodiles in Queensland are unaffected by cane toad toxin. ~Crocodiles in Queensland have evolved tolerance to the toxin. Crocodiles in the NT on the other hand have not been exposed to cane toads very long and most are still susceptible to the toxin.

Antibiotic resistance ~Antibiotics are poisonous to bacteria in a number of ways. Many antibiotics prevent bacteria from growing new cell walls. Not all bacteria are equally affected by all antibiotics. In any population of bacteria, there are likely to be some that have genes that make them more resistant to a particular antibiotic. ~There are now many bacteria which have evolved to become resistant to several common antibiotics.

The theory of Evolution by Natural Selection

Darwin and Wallace Theory Natural selection ~Selective pressures put

constraints on organisms and determine the better organism

Adaptations Structural adaptations -Shape and size of an organism

and the details of it physically

In animal; -Red kangaroos have a dense network of blood vessels on their forelegs close to the surface of

the skin to cool down more quickly In plant; -Eucalyptus leaves are long and narrow with thick waxy cuticle and sunken stomata to prevent water loss in a dry environment.

Physiological adaptations -Internal features that enable organism to survive -Also refers to biochemical reactions in cells and organelles.

In animal; -To minimise water loss the red kangaroo produces dry faeces and concentrated urine In plant; -Saltbush grows in hot and dry climates, has salt glands that excrete salt crystals to reflect heat.

Behavioural adaptations -Actions an organism takes for survival -Can be learnt or instinctive

In animal; Red kangaroo seeks shade on hot days In plant; -Some plants orientate their leaves to follow the sun for maximum light.

Effects of Environment Selection Pressure -It put constraints on organisms

and determine the better organism

Effects; -Survival of organisms -Abundance of a population -Diversity of an ecosystem -Evolution of a species

Effects of ___ on abundance & diversity of species;

-Abiotic -Can be physical or chemical - Availability of water, availability of oxygen and carbon dioxide, light intensity, temperature range, soil characteristics and salinity -Positive selection pressure = abundance increase -Negative selection pressure = abundance decrease

-Biotic -Food availability, predators, competitors, disease organisms, direct human influence, mates -It can be from the same or another species -Positive selection pressure = abundance increase

-Negative selection pressure = abundance decrease

Ecosystem Dynamics(Module 4) Define Example Population Dynamics Biotic Living things Producer (autotrophs)

-Grass Consumer (heterotrophs) -Animals

Abiotic Non-Living things -Wind 0Temperature -Soil Composition -Humidity

Impacts of biotic factors such;

-Predations -Relationship where a predator species will kill and consume a prey species -Increase the predator’s survival compared to prey’s

Predator and prey -Lion and Zebra -Bear and Fish -Rabbit and Lettuce

-Competition -An interaction between species in which both species are harmed(directly or indirectly)

Species that compete for territory, water, food or mate

-Symbiosis -Occurs when two or more organisms have a prolonged association that may benefit/ harm each member.

-Parasitism (One benefits other is affected) -Commensalism (One benefits other is unaffected) -Mutualism (Both species benefits)

Measuring populations -Sampling techniques Concept of Niche -Habitat -Food chain

Past Ecosystems Palaeontology ~The study of fossil remains. Aboriginal rock painting -Thylacine (Tasmanian tiger) rock painting)

~located at Ubirr in the East Alligator region of Kakadu (NT). was declared extinct in 1936, however was extinct on the mainland for 2000- 3000 years.

It is clear evidence of evolution because

• -Thylacine being sighted by Aboriginal inhabitants in the NT well before white settlement.

• -Changes over time suggest climate and species change.

Rock structure and formation

Iron banding ~Iron banding (Fe2O3) are distinct layers of sedimentary rock containing iron oxides. ~This indicates that conditions on early Earth were significantly different than today.

Marine fossils in the desert The presence of marine fossils in desert regions of the world clearly indicates that conditions in these regions have been significantly different to those of today.

Ice core drilling ~Ice cores are cylinders of ice drilled out of Arctic and Antarctic ice sheets. ~ Snow falling in Arctic and Antarctic regions doesn’t melt and encloses small bubbles of gases (eg. CO2 and CH4) and pollens in the atmosphere at the time the layer formed. ~ indicate that conditions on Earth have changed significantly.