Biology Exam - 2015

How do plants cope with the wind?

• Fewer Leaves: Less resistant to the wind,
• Less surface area: Less Resistance
• Flexible Trunks: Bend with the wind to cope with the force.
• Wider Base: Provides more stability.

FL, LSA, FT, WB,

LSTB - E.g Decideous Trees

Vacule, Rigid, Turgor Preassure, Turgid - VRPT

• Plant Cells have a vacule - when this is filled with water, it presses against the cell wall.
• This makes the cell rigid.
• This preassure is called turgor preassure, and the cell is said to be turgid.

• Plants make lignin.
• Lignin is laid down in Plant Tissues and makes them rigid.
• Tree trunks contain a lot of lignin. This creates Wood.

Lignin -> Wood, Plant Tissues: LWPT

Why do we need bones?

For support, movement, protection, making blood cells - SMPB

What is bone made of?

Bone, being a composite substance, is made up of Calcium Phosphate and Collagen. - CSCPC

Deconstructing Bone

Experiments: Vinegar for 1 week - bone falls apart - brittle, but 5% soak up of vinegar, heat until blackened - weighs less, very bendy. VBrIHBeL

Skull, Ribcage and Pelvis are were bones surround and protect organs. - SRP

Muscles are attached to bones. - M+B

Bones are linked by different types of joints, joints protected by cartalidge at the end and synovial fluid between them. - C@E, SF@Middle

• Where two bones meet, Three main types
• Fixed Joint, Hinge Joint, Ball and Socket Joint.
• Muscles control movement of Joints. they can pull bones into different positions.
• Tendons attach bones to muscle tissues
• Cartalage covers the bones in a protective substance so they don't wear away.
• Muscle is a tissue that can contract and makes up a part of the body - attached by tendons to the bone. Tendons do not streach.
• A muscle can relax and stop pulling, but it can't streach and push a bone back.
• Muscles work in pairs, wherever there is a muscle, there is another to work against it. The arrangement is known as an Antagonistic Pair.

Fish Swimming:

Types of Unwanted Movement

Rock, Roll, Yaw

Fins used to stabalize the fish

Anal fin, Pectoral fin, Caudal Fin

Direction:

• The Porpoise moves itself up and down, the fish move sideways.
• The Porpoise is a mammal.
• Mammals do not lay eggs.

Their fins displace the water.

Pillars and ZigZags:

The heavier the animal, the more likely they will have a pillar bone arrangement.

Elephants = Pillar Arrangement

Horse = ZigZag Arrangement

ZigZag is easier to move - they can bend their legs but can support less weight, Pillar is less easy to move - legs can't bend, but it can support more weight.

Why can't a whale live on land?

Because the whale's down force is only 4N in the water.

When it is on land, it's down force is 7N. This means that the bottom is flattened (like a balloon).

When it is on land, it's organs are crushed so it cannot breathe.

The longer the leg, the longer the stride: This usually means that the animal cab run faster.

However, the long legs must be moved by powerful muscles if the rate of movement is to remain fast. This means that the legs need to be light for the speed to improve.

Cheetah - HSBSHTH

Bigger Heart, Lungs and Liver: Pump blood faster,

Bigger Stride Length: Helps cheetah with speed,

Less Body Mass: Better Weight:Power Ratio

Very Streamlined: Reduces forces acting against cheetah.

Hard & Rigid Foot Pads and Claws: Helps cheetah move faster and grip better

Long Tail: Helps cheetah become more stable

Smaller Head: More Aerodynamic

In Mouth:

Saliva lubricates the food and starts breaking down Carbohydrates.

Gullet forms a passage for food to get to the stomach.

Stomach digests proteans and the hydrochloric acid kills micro-organisms.

Liver makes bile and the Gall-Bladder stores bile.

The Pancreas uses enzymes to break down the food. Duodenum is where most digestion occurs.

Small Intestine completes digestion.

Large Intestine absorbs water and creates faeces.

The rectum stores faeces.

The anus controls release of faeces.

• 1ml of DCPIP in test tube
• 1ml syringe with 0.1% of vit c
• add acid to DCPIP one drop at a time
• record number of drops required to discolor DCPIP
• repeat the above with fresh DCPIP and a fruit juice

Formula

% of Ascorbic Acid in juice = (no. drops of ascorbic acid / no. drops of fruit juice) * 0.1%

Incisors - Located in front and center of one or both teeth, used for holding, cutting or gnawing.

Incisors - HCG - F&C

Canines - Located either side of incisors, in one or both jaws, used for stabbing / tearing.

Canines - ST - Either side of incisors - O/B J

Pre-Molars/Molars - Located along sides and back of one or both jaws, used for grinding / shearing.

Pre-Molars/Molars - GS - S/B - O/B J

Herbivores: Incisors only - I

Carnivores: Incisors, Canines, Premolars - ICP

Omnivores: All types of teech

Insectivores: Long Incisors, Very Sharp Canines, Premolars and Molars - ICPM

Plaque: Sticky film of food & bacteria - SFB

Bacteria feed on food particles and produce acid - BFA

Acid dissolves cavities - AC

Acid, Bacteria and chemicals can access pulp, cavity and nerves.

Gum desease can also cause gums to bleed.

Ways to prevent Plaque: Flossing, Brushing your teeth.

Enzymes = Biological Catalysts

Substrate = Material to be broken down

When substrate has locked in place with Enzyme, it is known as an Enzyme substrate complex.

Carbohydrases break down Carbohydrates into simple sugars.

At Body Temperature (37 degrees C) the enzymes and substrates work at max rate.

At 4 degrees C, they lack energy

At 100 degrees C, the enzymes change shape thus denaturing the enzyme. the substrate does not fit into the active site and the substrate can't be broken down via that enzyme.

Why do we sample?

Sampling means you can get an idea of the 'whole' by trying/experimenting with only a bit of it.