W.O.W.'s Kingdom of Non-Stop-Homework-Always!: 08/25/10

Wow. What a week! Frist, we had the English Language CA2 paper on Monday, then the MT papers yesterday. Today's Mathematics paper was a blast (not sure in a good way or a bad way...) and tomorrow is the last CA2 paper: Science!

In this blog post, you will find some useful notes to help you revise for the Science paper.

The first section covers some of the key ideas and concepts you had learnt in the variou topics (especially Light and Heat). Next, you will be led through some of the ways to answer Science test questions, including some sample answers for commonly encountered types of Science questions. This section will help to hone your process skills.

KEY IDEAS AND CONCEPTS

1) Plants and Plant Parts (Lower block/P3/Chapter 16 in PSLE Guide/Pg 111 - 118)

Plants - Flowering (eg. Balsam plant) and non-flowering (eg. Bird's Nest fern) plants
Plant parts - Roots, root hair, stem, leaves, flowers, fruits and each of their functions
Identify and label the various plant parts
The presence of the green pigment called chlorophyll in the leaves of green plants which enables the food-making process of photosynthesis
Types of stems - weak vs strong, aerial vs underground, woody vs non-woody
Parts of a leaf - leaf blade, leaf stalk and veins (network vs parallel)
Types of leaf edges - entire edge, jagged/toothed edge, lobe edge
Types of leaf surfaces/textures - rough, smooth, waxy, hairy
Leaves that grow singly vs Leaves that grow in clusters
Flowers that grow singly vs Flowers that grow in clusters
Types of fruits - edible (can be eaten) vs inedible (cannot be eaten), fruits with one, a few and many seeds

2) Fungi, Bacteria and Micro-organisms (Lower block/P3/Chapter 5 in PSLE Guide/Pg 39 - 41)

Some examples of fungi - mushroom, bracket fungi, bread mould
Fungi are not plants - no roots and leaves; do not contain chlorophyll and cannot make their own food
Fungi reproduce through spores
Spores are found in spore cases (mould), sacs or gills (mushrooms)
Fungi are important because they are decomposers and help to break down dead plants and animals into simpler substances
Bread moulds cause food to spoil when they grow on them
Micro-organisms are tiny living things which can only be seen under a microscope
Some examples of micro-organisms - mould, yeast, penicillium, amoeba
Yeast is used in the making of bread
Penicillium (a type of mould) is used as an antibiotic in medicine

3) Life Cycles of Animals and Plants (Lower block/P3/Chapter 7 in PSLE Guide/Pg 54 - 62)

Life cycles are made up of a number of stages of growth which all living things go through - birth, growth, development and reproduction
The life cycle repeats itself to ensure the survival and continuity of thats species of living things

Animals with 2-stage life cycles - most mammals (eg. human being, dog, cow, etc)

Animals with 3-stage life cycles - frog (eggs - tadpole - adult frog), chicken (egg - chick - adult chicken), cockroach (egg - nymph - adult cockroach), grasshopper (egg - nymph - adult grasshopper), etc

Animals with 4-stage life cycles - butterfly (egg - larva/caterpillar - pupa - adult butterfly), moth, mosquito (egg - larva/wriggler - pupa - adult mosquito, housefly (egg - larva/maggot - pupa - adult housefly), mealworm beetle (egg - larva/mealworm - pupa - adult beetle), etc

Identify and name the different stages (eg. pupa stage)

Compare life cycles in terms of the number of Stages (2 vs 3 vs 4), Appearance between young and adult (alike vs not alike), Living habitat (land vs water), what they Eat

Plants have 4 stages in their life cycles - seed, seedling, young plant, adult plant (with flowers; with fruits)
The process of germination - seeds need water, air and warmth (not sunlight!) to germinate into seedlings
Seed leaves are not true leaves - they store and provide food for the seed to grow during germination as it cannot make its own food yet without the true leaves
True leaves have chlorophyll to enable them to make food

4) The Digestive System (Lower block/P3/Chapter 15 in PSLE Guide/Pg 108 - 110)

Identify and label organs in the digestive system - mouth, gullet, stomach, small intestine, large intestine, rectum and anus
Functions of each organ in the digestive system
Digestive juices act on food and break it down into simpler substances for the body to absorb

5) Air and the Respiratory System (Lower block/P3/Chapter 18 in PSLE Guide/Pg 122 - 130)

Air is a mixture of gases
Components of air - about 78% nitrogen, 21% oxygen, 0.03% carbon dioxide, water vapour and other gases
Oxygen is needed for burning - without oxygen, fire will extinguish itself
Carbon dioxide is needed for plants to photosynthesise when there is light

Breathing is not respiration
Breathing is the inhaling and exhaling of air
Respiration is the reaction in the body where oxygen and nutrients are used to produce carbon dioxide and energy
Identify and label the parts of the body in the human respiratory system - nose, mouth, windpipe, lungs, air sacs and diaphragm
Movement of diaphragm when inhaling and exhaling air

Plants have tiny openings on the leaves called stomata to take in and give out gases, and to prevent water from evaporating on a hot day

Fish and tadpoles breathe through gills in the water
Frogs breathe through their skin in the water and through their lungs on land

6) Matter and Its Three States (Lower block/P3/Chapter 8 in PSLE Guide/Pg 63 - 69)

Matter is anything that has mass and volume
Mass is the amount of matter in a substance and is measured using a lever balance
Volume is the amount of space that a substance occupies

There are three states of matter - solid, liquid and gas
Solids have definite shape and volume
Liquids have no definite shape but have definite volume
Gases have no definite shape nor volume; so gases can be compressed

7) Light and Shadows (Lower block/P3/Chapter 29 in PSLE Guide/Pg 256 - 263)

Light is a form of energy that enables us to see
Light travels in a straight line; it cannot bend
The sun, stars, fireflies, fire, light builds which are switched on are some sources of light
Light is absorbed by and bounced off (reflected) surfaces to allow our eyes to see the colours and such of the objects
Light reflected by an object enters our eyes to enable us to see it
Mirrors reflect light at a right-angle

Different materials allow different amounts of light to pass through (Pg 259)
Transparent materials - allow most light to pass through (eg clear plastic, glass) - little/no shadows
Translucent materials - allow some light to pass through (eg. frosted glass, thin paper) - light shadows
Opaque materials - do not allow light to pass through at all (eg. wood, metal) - dark shadows

Shadows are formed when light is blocked by an object
Shadows are formed in the direct opposite direction from the light source
The size of a shadow depends on the distance between the light source and the object
The further the object is from the light source, the smaller its shadow
The nearer the object is to the light source, the larger its shadow

At different times of the day, the sun casts different sizes of shadows of objects

8) Heat and Temperature (Lower block/P3/Chapter 30 in PSLE Guide/Pg 264 - 267)

Heat is a form of energy that makes things hot
Things that produce hear are known as sources of heat
Some sources of heat - the Sun, burning of fuels (eh. wood, coal), nuclear fission, electricity, friction

Temperature is a measurement of how hot a substance is.
A thermometer is used to measure the temperature of a substance.
There are two types of thermometers - clinical and laboratory (Pg 265)
Clinical thermometers are used to measure the temperature of the body (35*C to 42*C)
Laboratory thermometers are used during Science experiments to take more precise temperatures (-10*C to 110*C)