EOY biology revision tuesday

Name the 7 food groups

• Carbohydrates

• fats/lipids

• protein

• vitamins

• minerals

• fibre

• water

What is the test and result for starch

iodine solution, brown to blue,black

What is the test and result for glucose

Benedict’s solution, heat it at 80 degrees for 5 mins, blue to green to yellow to orange to red

What is the test and result for protein

Biuret solution, blue to lilac

What is the test and result for lipids

ethanol and water, pour ethanol then water, clear to cloudy white

What is lipids made of

3 fatty acids and a glycerol

What are proteins made of

amino acids

What are sources, function, and deficiency disease for Vitamin A

• Source-carrot, milk, butter, liver, sweet potato

• Function- good eyesight, healthy

  • Deficiency disease- sore eyes, poor night vision, unhealthy skin

What are sources, function, and deficiency disease for vitamin C

• Source-Oranges, lemons, limes

• Function-Tissue repair, resistance to disease

• Deficiency disease- scurvy

What are sources, function, and deficiency disease for vitamin D

• Source- fish, oil, milk, butter, made in body by sunlight

• Function- Strong bones and teeth

• Deficiency disease- rickets (soft bones)

What are the sources, function, and deficiency disease for calcium

• Source- Milk, Green veg

• Function- Strong bones and teeth

• Deficiency disease- soft bones

What are the sources, function, and deficiency disease for iron

• Source- Liver, meat, cocoa

• Function- Healthy red blood cells

• Deficiency disease- anaemia

What is digestion

Breaking down large insoluble molecules into small soluble molecules.

What is absorbtion

Taking soluble molecules from the gut into the bloodstream

What is assimilation

Food molecules absorbed are taken into cells of tissues and used for respiration or growth and repair.

What is egestion

Waste material called faeces leaves the body via the anus. Composed of undigested food, water, enzymes, dead cells, bile pigments and mucus.

What is the function of the gall bladder

Stores bile

What is the function of the small intestine

The main site for absorption of soluble products of digestion.

What is the function of the anus

Undigested waste leaves here

What is the function of the pancreas

Produces enzymes for digestion that enter the small intestine to aid the breakdown of food

What is the function of the rectum

To store faeces before it leaves the anus

What is the function of the oesophagus

Connects the mouth to the stomach. Muscles squeeze food down by peristalsis.

What is the function of the stomach

Food is churned and mixed and hydrochloric acid and enzymes are produced that break down protein.

What is the function of the mouth

Teeth chew food which is mixed with saliva. Saliva contains the enzyme called amylase which brakes down starch

What is the function of the epiglottis

Covers the trachea when swallowing to stop food entering the airways.

What is the function of the large intestine

Absorbs water from faeces leaving undigested food.

What is the function of the appendix

No purpose in humans

What is the function of the duodenum

The first 30cm of the small intestine. connects the stomach to the small intestine.

What is the function of the liver

Produce bile

What are enzymes

They make reactions happen faster.

What are the 2 main types of Enzymes and what do they do

Breakers-Speed up reactions that break down large molecules

Buildings-Speed up reactions where small molecules join together to make larger ones

How do enzymes work

Enzymes are made up of long chains of amino acids. These chains are folded to produce a shape called the active site. Other molecules called substrates fit into the active site and a reaction takes place.

What 2 things affect enzymes

Temperature and pH

What is a source and deficiency disease of iodine

Source-fish

Deficiency disease-goitre

What happens if the temperature is too high for an enzyme

The enzyme will denature meaning the substrate wont fit.

What are the 2 roles of bile

To neutralise stomach acid and make conditions in the duodenum slightly alkali.

Emulsifies fats giving them a greater surface area for lipase to act on.

Where is carbohydrase produced, secreted, what is its substrate and what are the products of the enzyme reaction.

• Produced- salivary gland

• Secreted- mouth

• Substrate- carbohydrates

• Products- glucose

Where is protease produced, secreted, what is its substrate and what are the products of the enzyme reaction

• Produced- pancreas and stomach

• Secreted- stomach, small intestine

• Substrate- protein

• Products- amino acids

Where is lipase produced, secreted, what is its substrate and what are the products of the enzyme reaction.

• Produced- pancreas

• Secreted- Small intestine

• Substrate- fats

• Products0 fatty acids, glycerol

What adaptions does the small intestine have to speed up digestion

• Villi for large surface area

• A thin lining

• A good blood supply

How thick is one villi

One cell

What do villi have on them

micro-villi

What is the word and symbol equation for aerobic respiration

Glucose + oxygen - carbon dioxide + water

What are the percentages for inspired and expired air

• Oxygen-Inspired,21% Expired,16%

• Carbon dioxide-Inspired,0.04% Expired,4%

• Nitrogen-Inspired,78% Expired,78%

• Water vapour- Inspired, variable Expired, saturated

What is anaerobic respiration

Respiration without using oxygen takes place in the cytoplasm. it produces less energy than aerobic.

What does anaerobic respiration produce and what effect does this have

It produces lactic acid because the glucose is only partly broken down. This accumulates in muscles causing pain and fatigue.

What is oxygen debt

After exercise we carry on breathing deeply. This is to bring oxygen into the body to break down the lactic acid.

Where is lactic acid broken down

The liver

What is fermentation

In the absence of oxygen, yeast and plants can respire anaerobically

what is the word Equation for fermentation

glucose- alcohol + carbon dioxide (energy)

What is the trachea

Tube that connects mouth to lungs

What are the ribs

outer cage of muscles that protect the lungs

What are intercostal muscles

Muscles between ribs allowing them to expand with the lungs

What are the bronchi

the first branch of the trachea. The trachea branches into 2 sections. 1 for each lung.

What are bronchioles

They branch from the bronchi and spread through the lungs

What are alveoli

They are ‘the leaves on the tree’ Little sacks that have a large surface area to diffuse oxygen into the blood

What is the pleural membrane

A protective layer for the lungs

What is pleural fluid

Helps to cushion the lungs.

What is the diaphragm

The main breathing muscle

What are the cells in the trachea that waft mucus towards the throat called

Ciliated epithelial cells

What is the mechanism of breathing and how does it work

The lungs inflate when the diaphragm is pulled down. This is because the lungs lose pressure so the air outside moves from area of high pressure to an area of low pressure.

What is the independent variable

The thing that you change in an experiment

What is the dependent variable

The thing that you measure in an experiment

What are the control variables

The things that you keep the same

What is the definition of accuracy

How close something is to the true value

What three things do cigarettes contain and how do they affect the lungs

• Nicotine- Makes arteries narrower

• Carbon monoxide- Stops red blood cells from carrying oxygen

• Tar- Causes lung damage and lung cancer due to it sticking to the lungs

What is the difference between a human and a fish circulatory system

• Fish system- Single circulatory system. The blood travels through the heart once for every complete circuit

• Human system- Double circulatory system. The blood passes the heart twice in one circuit. More efficient.

What is blood made from and in what percentages

55%plasma

45%blood cells

What are the 2 types of white blood cell and what do they do.

• Phagocytes- ‘Cell eaters’ engulf bacteria using enzymes.

• Lymphocytes- Send antibodies to fight the bacteria.

How do vaccines work

They inject a dead or weak version of a virus into your blood. The white blood cells then fight it. The memory cells are then stored away and when the same virus comes back the antibodies can be produced very quickly because of the memory cells.

What are features of an artery

• They carry blood from the heart

• Carry blood at high pressure

• Have thick wall

• No valves

• blood flows in pulses

• carry oxygenated blood

What are features of a vein

• Carry blood to the heart

• carry blood at low pressure

• have thinner walls

• have valves

• have little elastic fibres

• no pulses

• deoxygenated blood

What do valves do

Stop blood from going backwards in veins

What is the hole that blood flows through in a vein and artery called

lumen

What do capillaries do

They exchange substances between blood and the surrounding cells. Oxygen, digested food an other substances pass from the blood into the cells. Carbon dioxide and other waste substances pass from the cells into the blood. They have thin walls tomake diffusion easier.

How wide is a capillary

the width of a red blood cell

How thick is a capillary wall

one cell

Heart diagram

Where is the aorta going to

Around the body with oxygenated blood

Where is the vena cava coming from

The body carrying de oxygenated blood

Where is the pulmonary artery going to

The lungs with de oxygenated blood

Where is the pulmonary vein coming from

The lungs with oxygenated blood

Where is the tricuspid valve

between the right atrium and the right ventricle

Where is the bicuspid valve

Between the left atrium and the left ventricle

Where are the semi-lunar valves

Between the right ventricle and the pulmonary artery and also between the left ventricle and the aorta.

What is the cardiac cycle and what is each stage

The cardiac cycle is the sequence of events in one heartbeat

1. Diastole- when the muscle are relaxed. Blood flows into the atria from the veins.

2. Atrial systole- when the atria contract and force blood into the ventricles

3. Ventricular systole- is when the ventricles contract forcing blood out into the arterys.