AQA Biology Paper 1 GCSE

Flashcards for the 9-1 AQA Triple Biology Higher GCSE Paper 1 (Topics 1-4)

What is meant by organisational hierarchy

The organisation of living things in terms of significance

What biological molecules are enzymes made of?

Proteins

What is a substrate

the substance on which an enzyme acts.

What does bile do

Emulsifies fat, breaking it into smaller pieces.

What is a cell?

The basic unit of all living things.

What is an organ?

A group of different tissues that work together to perform a specific function

What is an organism

Any living thing

What is an organ system?

A group of organs that work together to make a system/specific function

What is the cell membrane?

A semi-permiable layer

What does the gall bladder do

It stores bile before it is released into the small intestine.

What does the pancreas do?

Makes and releases digestive juices containing enzymes to break down your food.

What does the stomach do

Organ where food is churned with digestive juices and acids

What happens in the small intestine

Nutrients are absorbed into the bloodstream

Where is bile produced?

Liver.

Where does bile move to meet the fats

Small intestine

What does bile do when it meets the fats

Breaks it down to make it easier to digest (it has a larger surface area for absorbtion)

What does the lipase enzyme digest the fat into?

Glycerol and fatty acids.

What happens to the glycerol and fatty acids?

Absorbed by small intestine into the bloodstream

What are enzymes

Proteins that act as biological catalysts

Define catalyst

Speeds up a chemical reaction.

What is metabolism (in terms of enzymes)

How fast the body can build up and break down enzymes.

What is the lock and key theory?

When specific enzymes and substrates fit perfectly in the active site to release amino acids

What is used to test for lipids?

Sudan III

What colour would Sudan ||| turn if lipids are present?

Red top layer.

What is used to test for starch?

Iodine

What is the colour change of Iodine if starch is present

Yellow/Brown -> Blue/Black

What is used to test for sugars?

Benedict's solution

What is the colour change in benedict's solution if sugars are present?

blue -> green/yellow (low) OR brown/red (high)

What is used to test for protein

Biuret

What is the independent variable

What you change.

What is the dependent variable

What you measure

What is the controlled variable?

What stays the same

What does amylase break down

Carbohydrates (into glucose)

What does protease break down?

Proteins into amino acids

What does lipase break down?

Lipids into fatty acids and glycerol.

Define denaturation

The irreversible, structural change in an enzyme that makes it unable to catalyse due to the substrate no longer fitting its active site.

true or false - Enzymes are chemical catalysts.

FALSE! They are biological catalysts

What is the average pH of the stomach

pH 1-2.

What is the optimum pH for protease?

pH 2.

What is the pH of hydrochloric acid?

2.

Where is lipase produced?

Pancreas

Average body temperature

37 degrees Celsius

Which chemical test is used to detect the presence of glucose in food?

Benedict's test

The enzyme amylase breaks down which food chemical?

Starch

What conditions increase the rate of fat breakdown by lipase?

High temperatures

What is the optimum temperature for enzymes?

Body temperature - 37`C

Name any molecules that are too big to be digested so they must be broken down into smaller molecules.

Starch

Proteins

Fats

What does amylase break down

Starch

What is the function of the large intestine

Excess water is absorbed from the food

Is pH 2 acidic or alkaline?

Acidic

REMEMBER "Benedict eats sugar."

ye

REMEMBER "Starch shares no same letters as iodine so they are together"

ye

How to remember what is used for lipids

Lots of the letter "I" Sudan |||

Proteins memorisation technique.

Just weird so biuret.

Where are the lungs

Thorax

Where does gas exchange happen

Alveoli of the lungs.

What does the blood passing next to the alveoli have lots of?

Carbon Dioxide.

How are lungs adapted for gaseous exchange

Millions of alveoli to increase surface area

Where does oxygen you breathe in go after the trachea

Two bronchi into each lung

Oxygen is diffused out of the ____ into the ___ through diffusion

Alveolus (HC)

Blood (LC).

What are the components of the circulatory system

Heart, blood vessels and blood

What does the right ventricle do?

pumps deoxygenated blood to the lungs

What does the left ventricle do

pumps oxygenated blood to the other organs of the body.

What are the walls of the heart made of?

Muscle tissue

What do arteries do

Carry blood away from the heart

What veins do?

carry blood to the heart

What do capillaries do?

Very small thin walls that carry blood super close to every cell to exchange substances through their permeable walls.

Describe artery walls.

Thick, strong and elastic

What is the name of the hole through blood vessels?

The lumen

How many cells thick are capillary walls

One cell.

What controls your resting heartrate

A group of cells in the right atrium.

What do the cells controlling your resting heartrate do?

Produce small electric impulses causing the muscle cells to contract.

What is an artificial pacemaker?

A device that uses electrical impulses to regulate the beating of the heart or to reproduce the rhythm of the heart beat.

What is the trachea lined with to reinforce its strength?

Rings of cartilage

What comes from each bronchi

Bronchioles

What is the function of the bronchioles?

Take the air deeper into the lungs

What are intercoastal muscles

Muscles between the ribs that relax and contract with the diaphragm.

Where is the diaphragm located

A flat muscle under the lungs

What does plasma do

Transports digested food molecules around the body

What do red blood cells do?

Transport oxygen.

What do white blood cells do?

Fight diseases and infections

What gives red blood cells their red colour

Haemoglobin.

Name adaptations of the red blood cell

No nucleus to make space for more haemoglobin

Small and flexible

Biconcave shape to maximise surface area.

True or False: Arteries have a wide lumen

False - that is veins.

What are platelets

Cell fragments.

What do platelets do?

Help blood clot at a wound to prevent infection.

Describe what happens in coronary heart disease.

Coronary arteries get blocked by layers of built up fat, making them small and restricting blood flow and gas exchange.

What medical device can be surgically inserted to decrease risk of heart failure

Stents - tubes inserted inside arteries to keep them open and working

What can cigarette smoke immobilise in the trachea?

Cilia.

What is the name given to chemicals that can cause cancer?

Carcinogens.

What is a tumour?

A group of uncontrollably dividing cancerous cells.

Describe benign tumours.

Not cancerous

Slow growing.

Contained in one area

Easily removed.

Describe malignant tumours

Cancerous.

Swiftly invades adjacent cells and tissues.

Spread and travel through the bloodstream

What step in mitosis is skipped in cancerous cells

Interphase

What does the epidermal tissue do

Covered with waxy cuticle to reduce water loss.

What is the palisade mesophyll

Main site of photosynthesis at top of the leaf with many chloroplasts

What does xylem transport

Water and minerals

What reinforces xylem?

Lignin

What does phloem transport?

delivers nutrients.

What does the spongy mesophyll do

Big air spaces to increase the rate of diffusion