Friday, 27 April 2012
Thursday, 19 April 2012
Wednesday, 11 April 2012
Animal A: Ants
Animal B: Aphids
How do they benefit each other:
Ants feed on 'honeydew' excreted by the Aphids. This 'honeydew' is high in sugar content. In turn, the Ants protect the Aphids from its predators such as the Ladybug.
Saturday, 7 April 2012
Wednesday, 28 March 2012
- Protista with mitochondria include, Trypanosoma, a genus of blood parasites.
- Simplest of the eukaryotes.
Flowering Plants are divided into two groups:-
~ One seed leaf(Monocotyledons) about 50000 species
Seeds produce one seed leaf on germination
Leaves have veins running in parallel about their length
Vascular tissue is scattered randomly throughout the stem
Includes lilies, grasses and many related cereal crops, and among trees, the fruit-bearing palms
~ Two seed leaves(Dicotyledons) about 200000 species
Seeds produce two seed leaves on germination
Generally more complex than Monocotyledons
Veins spread net-like across their leaves
Vascular tissue is arrange in an orderly ring around the stem
Includes most flowering plants, and many hardwood trees, such as oaks, limes and beeches.
Flowering plant reproduction:-
Male reproductive organs - Stamen
~ Anther - contains pollen sacs which releases grains of pollens, which are the male reproductive cells
~ Filament - supports anther
Female reproductive organs - Pistil
~ Stigma - it has a sticky surface which traps pollen grains that lands or touch it
~ Style - where pollen tubes grow
~ Ovary - contains one or more ovules. It develops into a fruit, after fertilization, which protects the seed inside
~ Ovule - contains the egg nucleus, which are the female reproductive cells. The ovules will develop into seeds after fertilization.
Some plants do not have male and female reproduction organs
~ It is a process by which a new plant arise or are obtained not by seeds or spores, but their plant parts
- Underground Stems
- Bulb: daffodil, onion, hyacinth
- Corms: crocus, water-chestnut, coco-yam
- Runners: strawberry, spider plant
- Rhizomes: ginger, iris, marram grass, lotus
- Tubers: Potato
~ Non-Flowering Plants do not bear flowers at all
~ Non-Flowering Plants are divided into ferns and mosses
- Mosses are usually very small in size and prefer to live in damp, shady areas
- Ferns often have large leaves that help them to live in places where there is little sunlight
Non-Flowering Plant reproduction:-
~ reproduce by spores
some spores are found in the spore bags located on the underside of mature leaves - e.g. Fern
while some spores are found in the spore bags located at the end of the stalks - e.g. Moss
~ When the spores are mature, they are released in to the air and carried by the wind or water to new places.
~ Conifers reproduce by seeds produced in the cones
Done By: Danish, Fathiah, Jemaimah, Joshua
Tuesday, 27 March 2012
- Reproduces through spores
- Does not have flowers
- Asexual reproduction
- It has great adaptability
The flower is the reproductive organ of all flowering plants.
-male reproduction parts
The stamen is made up of two main parts:
1. The filament is a stalk which supports the anther.
2. The anther is where the pollen (sperm) is made, and the pollen travels to the stigma on the female part of the plant.
-female reproduction parts
The pistil is made up of three main parts:
1. On the top is the stigma. It's sticky, and collects the pollen from the anther. Either self-pollination (within the same plant) or cross-pollination (between two different plants) occurs.
2. In the middle is the style, the thin, slender tube which connects the stigma to the ovary. Pollen travels through it to get to the ovary.
3. The ovary is where fertilization takes place. It makes ovules (eggs). The ovules unite with the pollen. A fertilized egg becomes a seed and the ovary develops into a fruit.
Unlike non-flowering plants, flowering plants produce fruits after the flower is being fertilized. The flower withers away and the fruit starts to grow.
Seeds are produced by all flowering plants. Seeds are dispersed in different ways, some of the examples are by wind, by clinging onto the fur of animals and by water.
1. Fish are ectothermic, aquatic vertebrates.
2. Their skin is generally covered with scales.
3. Their limbs are modified into fins for swimming.
4. They breathe with gills.
5. They lay eggs that must be in water.
1. Amphibians are ectothermic vertebrates.
2. Their skin lacks scales, hair, and feathers, and is either smooth (like a frog) or rough (like a toad). They are dependent upon moisture and subject to desiccation; their skin must remain moist to aid in breathing.
3. They lay eggs in water, which hatch into an intermediate life form (tadpole or larva) that usually breathes with gills, and change into the adult form that breathes air and can live outside water.
4. They have three-chambered hearts.
5. They lack claws on their toes.
3. They have three-chambered hearts (except for alligators and crocodiles, which have four-chambered hearts).
4. They have claws on their toes (except those which do not have legs, such as legless lizards).
5. They are the first animals, in evolution, to develop the amniotic egg. This allows reptiles to lay eggs on land.
2. Their skin is covered with feathers.
3. They have four-chambered hearts.
4. Their bones are lightweight and usually hollow.
5. Their forelimbs are modified as wings.
An invertebrate is an animal without a backbone.
Invertebrates are a very diverse group of species, including:
- Crustaceans (lobsters and crabs)
- Mollusks (squids, snails and clams)
Characteristics common among invertebrates:
- All of them lack a backbone
2. These soft bodied animals maintain their body shape by maintaining their internal pressure. Some invertebrates have hard outer covering called as exoskeleton to protect them from their predators.
3. The body of the invertebrates is of two types. They are radial symmetry (no left or right sides) and the other one is called as bilateral symmetry. (Can be divided in one plane into two mirror-image halves)
4. Habitat: The invertebrates are generally found every where in air, water and soil.
5. Shape: The invertebrates are various in shape. Some do not have any regular shape like amoeba. It changes its shape. The rest of the invertebrate have some definite shape. Some of them are like plant appearance,ribbon-like, vermiform and star.