BIOLOGY NOTES
FORM 2
A HEALTHY DIET
NUTRIENTS
A CHEMICAL THAT IS NEEDED BY THE BODY TO KEEP IT IN GOOD HEALTH IS CALLED A NUTRIENTS.
THE HUMAN BODY NEEDS A LARGE NUMBER OF DIFFERENT NUTRIENTS TO KEEP IT HEALTHY. THEY
CAN BE DIVIDED UP INTO THE FOLLOWING NUTRIENT GROUPS:





CARBOHYDRATES
FATS
PROTEINS
VITAMINS
MINERALS
IN ADDITION TO THESE NUTRIENTS YOUR BODY NEEDS WATER. IT ACCOUNTS FOR 70% OF THE
BODY’S WEIGHT AND PROVIDES SUPPORT FOR CELLS. IT CARRIES DISSOLVED MATERIALS AROUND
THE BODY AND HELPS IN CONTROLLING BODY TEMPERATURE.
NB. FIBRE IS ALSO NEEDED BY THE BODY.
CARBOHYDRATES
CARBOHYDRATES ARE MADE FROM THE ELEMENTS CARBON, HYDROGEN AND OXYGEN. THE ATOMS
OF THESE ELEMENTS ARE LINKED TOGETHER TO FORM MOLECULES OF SUGAR. THERE ARE
DIFFERENT TYPES OF SUGAR MOLECULE BUT THE MOST COMMONLY OCCURING IS GLUCOSE.
GLUCOSE MOLECULES LINK TOGETHER IN LONG CHAINS TO MAKE LARGER MOLECULES SUCH AS
STARCH. GLUCOSE AND STARCH ARE TWO OF THE MOST WIDELY KNOWN CARBOHYDRATES BUT
THERE ARE OTHERS, SUCH AS CELLULOSE.
HOW THE BODY USES CARBOHYDRATES?
CARBOHYDRATES CONTAIN A LARGE AMOUNT OF ENERGY THAT CAN BE RELEASED QUICKLY INSIDE
THE BODY. THEY ARE USED AS FUEL TO PROVIDE THE ENERGY FOR KEEPING THE BODY ALIVE.
FIBRE
CELLULOSE IS A CARBOHYDRATE WHICH MAKES UP THE WALLS OF PLANT CELLS. THE CELLULOSE IN
FOOD IS KNOWN AS DIETARY FIBRE. IT IS FOUND IN FOODS SUCH AS WHOLEMEAL BREAD, FRUIT
AND VEGETABLES. WE CANNOT DIGEST FIBRE BUT IT HELPS TO MOVE FOOD ALONG THE
INTESTINES. AS THE FIBRE MOVES THROUGH THE LARGE INTESTINE, BACTERIA FEED ON IT AND
TOGETHER THE FIBRE AND BACTERIA ADD BULK TO THE FOOD. THIS HELPS THE MUSCLES OF THE
LARGE INTESTINE PUSH THE FOOD ALONG. FIBRE ALSO TAKES UP WATER LIKE A SPONGE AND THIS
MAKES THE UNDIGESTED FOODS WHICH FORM THE FAECES SOFT AND EASY TO RELEASE FROM THE
BODY. IF A PERSON’S DIET LACKS FIBRE, THEY MAY SUFFER FROM BOWEL PROBLEMS SUCH AS
CONSTIPATION.
FATS
FATS ARE MADE OF LARGE NUMBERS OF CARBON AND HYDROGEN ATOMS LINKED INTO LONG
CHAINS TOGETHER WITH A FEW OXYGEN ATOMS. THERE ARE TWO KINDS OF FATS, THE SOLID FATS
PRODUCED BY ANIMALS, SUCH AS LARD, AND THE LIQUID FAT OR OIL PRODUCED BY PLANTS, SUCH
AS SUNFLOWER OIL.
HOW THE BODY USES FATS?
FATS ARE NEEDED FOR THE FORMATION OF CELL MEMBRANES. THEY ALSO CONTAIN EVEN LARGER
AMOUNTS OF ENERGY THAN CARBOHYDRATES. THE BODY CANNOT RELEASE THE ENERGY IN FATS
AS QUICKLY AS THE ENERGY IN CARBOHYDRATES SO FATS ARE USED TO STORE ENERGY. IN
MAMMALS THE FAT FORMS A LAYER UNDER THE SKIN. THIS ACTS AS A HEAT INSULATOR AND HELPS
TO KEEP THE MAMMALS WARM IN COOL CONDITIONS. MANY MAMMALS INCREASE THEIR BODY
FAT IN THE AUTUMN SO THAT THEY CAN DRAW ON THE STORED ENERGY IF LITTLE FOOD CAN BE
FOUND IN WINTER. SOME PLANTS STORE OIL IN THEIR SEEDS.
PROTEINS
PROTEINS ARE MADE FROM ATOMS OF CARBON, HYDROGEN, OXYGEN AND NITROGEN. SOME
PROTEINS ALSO CONTAIN SULFUR. THE ATOMS OF THESE ELEMENTS JOIN TOGETHER TO MAKE
MOLECULES OF AMINO ACIDS. AMINO ACIDS LINK TOGETHER INTO LONG CHAINS TO FORM
PROTEINS MOLECULES.
HOW THE BODY USES PROTEINS?
PROTEINS ARE NEEDED FOR BUILDING THE STRUCTURES INSIDE CELLS AND IN THE FORMATION OF
TISSUES AND ORGANS. THEY ARE NEEDED FOR THE GROWTH OF THE BODY, TO REPAIR DAMAGED
PARTS, SUCH AS CUT SKIN, AND TO REPLACE TISSUES THAT ARE CONSTANTLY BEING WORN AWAY,
SUCH AS LINING OF THE MOUTH.
CHEMICALS THAT TAKE PART IN THE REACTIONS FOR DIGESTING FOOD AND IN SPEEDING UP
REACTIONS INSIDE CELLS ARE CALLED ENZYMES. THESE ARE ALSO MADE FROM PROTEINS.
VITAMINS
UNLIKE CARBOHYDRATES, FATS AND PROTEINS, WHICH ARE NEEDED BY THE BODY IN LARGE
AMOUNTS, VITAMINS ARE NEEDED IN ONLY SMALL AMOUNTS. WHEN VITAMINS WERE FIRST
DISCOVERED, THEY WERE NAMED AFTER LETTERS OF ALPHABET. LATER, WHEN THE CHEMICAL
STRUCTURE OF THEIR MOLECULES HAD BEEN WORKED OUT, THEY WERE GIVEN CHEMICAL NAMES.
HOW THE BODY USES VITAMINS?
EACH VITAMIN HAS ONE OR MORE USES IN THE BODY. VITAMIN A IS INVOLVED IN ALLOWING THE
EYES TO SEE IN DIM LIGHT AND IN MAKING A MUCUS LINING TO THE RESPIRATORY, DIGESTIVE AND
EXCRETORY SYSTEMS WHICH PROTECTS AGAINST INFECTION FROM MICROORGANISMS.
THERE ARE SEVERAL B VITAMINS OF WHICH B1 (THIAMIN) IS AN EXAMPLE.
A LACK OFVITAMIN C CAUSES THE DEFICIENCY DISEASE CALLED SCURVY. AS THE DISEASE DEVELOPS,
BLEEDING OCCURS AT THE GUMS IN THE MOUTH, UNDER THE SKIN AND INTO THE JOINTS. DEATH
MAY OCCUR DUE TO MASSIVE BLEEDING IN THE BODY.
VITAMIN D HELPS THE BODY TAKE UP CALCIUM FROM FOOD TO MAKE STRONG BONES AND TEETH.
CHILREN WHO HAVE A LACK OF VITAMIN D IN THE DIET DEVELOP THE DEFICIENCY DISEASE CALLED
RICKETS IN WHICH THE BONES DO NOT DEVELOP TO THEIR FULL STRENGTH AND MAY THEREFORE
BEND. THIS IS SEEN PARTICULARLY IN THE LEG BONES.
VITAMIN
A
B1
C
D
EFFECT ON BODY
INCREASED RESISTANCE TO DISEASE.
HELPS EYES TO SEE IN THE DARK.
PREVENTS DIGESTIVE DISORDERS.
PREVENTS THE DISEASE BERIBERI.
PREVENTS THE DISEASE SCURVY IN WHICH GUMS
BLEED AND THE CIRCULATORY SYSTEM IS
DAMAGED.
PREVENTS THE DISEASE RICKETS IN WHICH
BONES BECOME SOFT AND LEG BONES OF
CHILDREN MAY BEND.
GOOD SOURCES
MILK, LIVER, COD-LIVER OIL
BREAD, MILK, BROWN
RICE, SOYABEAN, POTATO
BLACKCURRANT, ORANGE,
LEMON, PAPAYA, GUAVA
EGG YOLK, BUTTER, CODLIVER OIL, PILCHARD,
HERRING, SUNLIGHT
MINERALS
THE BODY NEEDS TWENTY DIFFERENT MINERALS TO KEEP HEALTHY. SOME MINERALS, SUCH AS
CALCIUM, ARE NEEDED IN LARGE AMOUNTS BUT OTHERS, SUCH AS ZINC, ARE NEEDED IN ONLY TINY
AMOUNTS AND ARE KNOWN ARE TRACE ELEMENTS.
HOW THE BODY USES MINERALS?
EACH MINERAL MAY HAVE MORE THAN ONE USE. FOR EXAMPLE, CALCIUM IS NEEDED TO MAKE
STRONG BONES AND TEETH. IT IS ALSO NEEDED TO MAKE MUSCLES WORK AND FOR BLOOD TO
CLOT. A LACK OF CALCIUM IN THE DIET CAN LEAD TO WEAK BONES AND HIGH BLOOD PRESSURE.
THE MINERAL IRON IS USED TO MAKE THE RED BLOOD PIGMENT CALLED HAEMOGLOBIN.
WATER
ABOUT 70% OF THE HUMAN BODY IS WATER. THE BODY CAN SURVIVE FOR ONLY A FEW DAYS
WITHOUT A DRINK OF WATER. EVERY CHEMICAL REACTION IN THE BODY TAKES PLACE IN WATER.
THE BLOOD IS MADE MAINLY FROM WATER. IT IS THE LIQUID THAT TRANSPORTS ALL THE OTHER
BLOOD COMPONENTS AROUND THE BODY. WATER IS USED TO COOL DOWN THE BODY BY THE
EVAPORATION OF SWEAT FROM THE SKIN.
THE HUMAN BODY
DIGESTIVE SYSTEM
THE DIGESTIVE SYSTEM BREAKS DOWN FOOD INTO TINY PARTICLES WHICH ARE ABSORBED INTO
THE BLOOD. THESE PARTICLES PROVIDE ENERGY FOR THE BODY TO GROW, REPAIR ITSELF AND
REMAIN HEALTHY. FOOD THAT CANNOT BE BROKEN DOWN IS RELEASED FROM THE BODY AS
FAECES (POO).
PARTS OF THE DIGESTIVE SYSTEM
THE DIGESTIVE SYSTEM IS MADE UP OF KEY PARTS, EACH OF WHICH HAS A DIFFERENT FUNCTION.
FOOD PASSES THROUGH MOST OF THESE PARTS IN A JOURNEY FROM THE MOUTH TO THE ANUS.
FUNCTION’S OF DIGESTIVE ORGANS
MOUTH - DIGESTION OF FOOD STARTS IN THE MOUTH. TEETH BREAK DOWN THE FOOD AND MIX IT
WITH THE ENZYMES IN SALIVA.
OESOPHAGUS - THIS IS A THIN TUBE THAT CONNECTS THE MOUTH TO THE STOMACH.
LIVER - THIS RELEASES A CHEMICAL CALLED BILE INTO THE INTESTINES. BILE BREAKS DOWN LIPIDS IN
THE FOOD.
STOMACH - THIS IS A MUSCULAR BAG WHICH MIXES FOOD AND DRINK WITH ACID.
PANCREAS - THIS RELEASES ENZYMES INTO THE INTESTINES WHICH BREAK DOWN CARBOHYDRATES,
PROTEIN AND LIPIDS IN FOOD.
SMALL INTESTINE - HERE, CARBOHYDRATES, PROTEINS AND LIPIDS DIGEST. THE NUTRIENTS
PRODUCED ARE THEN ABSORBED INTO THE BLOOD.
LARGE INTESTINE - FOOD WHICH CANNOT BE BROKEN DOWN - MAINLY FIBRE - PASSES INTO THE
LARGE INTESTINE. WATER IS ABSORBED INTO THE BLOOD
RECTUM - ANY UNDIGESTED FOOD PASSES INTO THE RECTUM WHERE IT IS STORED AS FAECES.
ANUS - THIS IS THE OPENING AT THE VERY END OF THE DIGESTIVE SYSTEM THROUGH WHICH
FAECES LEAVES THE BODY.
PROCESS OF DIGESTION
DIGESTION IS A COMPLEX PROCESS WITH MULTIPLE SUB PROCESSES. THESE WILL BE MADE CLEAR.
MECHANICAL AND CHEMICAL DIGESTION
TEETH BREAK DOWN FOOD IN THE MOUTH MECHANICALLY, THIS MEANS THEY GRIND IT UP.
CHEMICAL DIGESTION OCCURS WHEN ENZYMES DIGEST FOOD INTO NUTRIENTS.
BILE IS PRODUCED BY YOUR LIVER AND STORED IN THE GALL BLADDER. THIS IS RELEASED INTO THE
SMALL INTESTINE TO BREAK DOWN LARGE MOLECULES OF LIPIDS INTO SMALLER ONES. THIS IS NOT
DIGESTION BECAUSE IT DOESN’T BREAK DOWN LIPIDS INTO NUTRIENTS, JUST SMALLER DROPLETS.
THIS IS CALLED EMULSIFICATION AND INCREASES THE SURFACE AREA FOR ENZYMES TO ACT UPON.
MOVING FOOD THROUGH THE DIGESTIVE SYSTEM
DIGESTED FOOD IS MOVED THROUGH THE OESOPHAGUS, AND SMALL AND LARGE INTESTINES BY
MUSCLES IN THEIR LININGS THAT SQUEEZE IT ALONG IN A PROCESS
CALLED PERISTALSIS. SQUEEZING A TENNIS BALL THROUGH A PAIR OF TIGHTS IS A GOOD MODEL
FOR THIS PROCESS.
ABSORBING FOOD AND WATER
THE INTESTINES HAVE LOTS OF TINY FOLDS IN THEM WHICH CREATE A LARGE SURFACE AREA FOR
ABSORBING NUTRIENTS AND WATER. IN THE SMALL INTESTINE THERE ARE ALSO SPECIALISED CELLS
CALLED VILLI WHICH HAVE A TINY HAIR-LIKE STRUCTURE POKING INTO THE SMALL INTESTINE TO
ABSORB DIGESTED FOOD.
VILLI IN THE INTESTINE
REPRODUCTIVE SYSTEM
MALE AND FEMALE REPRODUCTIVE SYSTEMS ALLOW HUMAN REPRODUCTION. FERTILISATION
OCCURS WHEN A SPERM AND EGG JOIN TO FORM AN EMBRYO. AN EMBRYO DEVELOPS INTO AN
UNBORN BABY IN THE UTERUS DURING PREGNANCY.
GAMETES AND FERTILISATION
HUMANS REPRODUCE THROUGH SEXUAL REPRODUCTION. THIS PRODUCES OFFSPRING THAT ARE
GENETICALLY UNIQUE BECAUSE HALF OF THEIR GENETIC MATERIAL - DNA - COMES FROM EACH
PARENT.
GAMETES ARE THE MALE AND FEMALE SEX CELLS:
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
EGG/OVUM ARE FEMALE GAMETES
SPERM ARE MALE GAMETES
IN SEXUAL REPRODUCTION, A MALE AND FEMALE GAMETE CAN JOIN TOGETHER. THIS IS
FERTILISATION. THESE GAMETES ARE SPECIALISED CELLS WHICH HAVE ADAPTATIONS TO INCREASE
THE CHANCES OF FERTILISATION AND SUCCESSFUL DEVELOPMENT OF A BABY.
MALE REPRODUCTIVE SYSTEM
THE FUNCTION OF THE MALE REPRODUCTIVE SYSTEM IS TO PRODUCE SPERM CELLS - MALE
GAMETES - AND RELEASE THEM INSIDE A FEMALE.
THE MALE REPRODUCTIVE SYSTEM HAS TWO TESTES (SINGULAR: TESTIS). THESE ARE CONTAINED IN
A BAG OF SKIN CALLED THE SCROTUM. THE TESTES HAVE TWO FUNCTIONS:
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
TO PRODUCE MILLIONS OF SPERM
TO MAKE MALE SEX HORMONES, WHICH AFFECT THE WAY BODIES DEVELOP.
DURING EJACULATION THE SPERM PASS THROUGH THE SPERM DUCTS AND MIX WITH FLUIDS
PRODUCED BY THE GLANDS. THE FLUIDS PROVIDE THE SPERM CELLS WITH NUTRIENTS. THE
MIXTURE OF SPERM AND FLUIDS IS CALLED SEMEN. THIS PASSES OUT OF THE PENIS.
URINE ALSO PASSES FROM THE BODY THROUGH THE PENIS BUT NOT AT THE SAME TIME. THE
URETHRA IS THE TUBE INSIDE THE PENIS THAT CAN CARRY BOTH URINE OR SEMEN. A RING OF
MUSCLE MAKES SURE THAT THERE IS NO CHANCE OF URINE AND SEMEN GETTING MIXED UP.
FEMALE REPRODUCTIVE SYSTEM
THE FEMALE REPRODUCTIVE SYSTEM HAS TWO OVARIES (SINGULAR: OVARY). THESE HAVE TWO
FUNCTIONS:
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
THEY CONTAIN UNDEVELOPED EGGS (PLURAL: OVA, SINGULAR: OVUM). THESE ARE
PRESENT FROM BIRTH.
TO MAKE FEMALE SEX HORMONES, WHICH AFFECT THE WAY BODIES DEVELOP AND
ALSO REGULATES THE MENSTRUAL CYCLE.
EACH OVARY IS CONNECTED TO THE UTERUS BY AN OVIDUCT. THE OVIDUCT IS LINED WITH CILIA,
WHICH ARE TINY HAIRS ON CELLS. AS PART OF THE MENSTRUAL CYCLE, AN OVUM DEVELOPS,
BECOMES MATURE AND IS RELEASED FROM AN OVARY. THE CILIA MOVE THE OVUM ALONG THE
OVIDUCT AND INTO THE UTERUS.
THE UTERUS IS A MUSCULAR BAG WITH A SOFT LINING. THE UTERUS IS WHERE A BABY DEVELOPS
UNTIL BIRTH. THE CERVIX IS A RING OF MUSCLE AT THE LOWER END OF THE UTERUS. IT KEEPS THE
BABY IN PLACE DURING PREGNANCY.
THE VAGINA IS A MUSCULAR TUBE THAT LEADS FROM THE CERVIX TO THE OUTSIDE OF THE BODY. A
PENIS GOES INTO THE VAGINA DURING SEXUAL REPRODUCTION. THIS IS ALSO WHERE MENSTRUAL
BLOOD LEAVES THE BODY AND WHERE A BABY EXITS DURING BIRTH.
GESTATION AND BIRTH
A FERTILISED OVUM DIVIDES TO FORM A BALL OF CELLS CALLED AN EMBRYO. THE EMBRYO
ATTACHES TO THE LINING OF THE UTERUS. IT BEGINS TO DEVELOP INTO A FETUS AND THEN
BECOMES A BABY WHEN IT IS BORN. IT TAKES ABOUT 40 WEEKS FOR A FETUS TO DEVELOP IN THE
UTERUS. THIS TIME IS CALLED GESTATION.
A FETUS DEVELOPS IN THE UTERUS INTO A BABY READY TO BE BORN
THE FETUS RELIES UPON ITS MOTHER FOR:




PROTECTION AGAINST KNOCK AND BUMPS, AND TEMPERATURE CHANGES
OXYGEN FOR RESPIRATION
NUTRIENTS - FOOD AND WATER
REMOVAL OF WASTE SUBSTANCES
THE FETUS IS PROTECTED BY THE UTERUS AND A LIQUID CALLED AMNIOTIC FLUID.
THE PLACENTA IS AN ORGAN RESPONSIBLE FOR PROVIDING OXYGEN AND NUTRIENTS, AND
REMOVING WASTE SUBSTANCES. IT GROWS INTO THE WALL OF THE UTERUS AND IS JOINED TO THE
FETUS BY THE UMBILICAL CORD. THE MOTHER'S BLOOD DOES NOT MIX WITH THE BLOOD OF THE
FETUS, BUT THE PLACENTA LETS SUBSTANCES PASS BETWEEN THE TWO BLOOD SUPPLIES:

OXYGEN AND NUTRIENTS DIFFUSE ACROSS THE PLACENTA FROM THE MOTHER TO
THE FETUS

CARBON DIOXIDE AND OTHER WASTE SUBSTANCES DIFFUSE ACROSS THE PLACENTA
FROM THE FETUS TO THE MOTHER
THE BLOOD OF THE MOTHER AND FETUS DO NOT MIX, BUT SUBSTANCES DIFFUSE ACROSS THE
PLACENTA
HEALTH AND LIFESTYLE
OTHER SUBSTANCES CAN ALSO PASS THROUGH THE PLACENTA, INCLUDING RECREATIONAL DRUGS
AND ALCOHOL. DRUGS CAN AFFECT THE FETUS - SLOWING THE GROWTH OF THE FETUS, REDUCING
THE AMOUNT OF OXYGEN AND CAUSING B LEEDING - WHICH CAN BE LIFE THREATENING.
DRINKING ALCOHOL OR SMOKING WHILE PREGNANT ARE ALSO DANGEROUS AND CAN INCREASE
THE RISK OF STILLBIRTH, PREMATURE BIRTH AND LONG-TERM HEALTH CONDITIONS.
BIRTH
AFTER GESTATION, THE BABY IS READY TO BE BORN. THE CERVIX RELAXES AND MUSCLES IN THE
WALL OF THE UTERUS CONTRACT. WAVES OF MUSCLE CONTRACTIONS PUSH THE BABY OUT OF THE
MOTHER'S BODY THROUGH THE VAGINA. IN SOME CASES, A CAESAREAN SECTION IS PERFORMED AS
A VAGINAL BIRTH IS NOT POSSIBLE FOR HEALTH OR MEDICAL REASONS.
CIRCULATORY SYSTEM
THERE ARE THREE TYPES OF BLOOD VESSEL: ARTERIES, VEINS AND CAPILLARIES. THE HEART IS A
MUSCULAR ORGAN THAT PUMPS BLOOD AROUND YOUR CIRCULATORY SYSTEM. THE CIRCULATORY
SYSTEM IS THE HEART AND ALL THE BLOOD VESSELS IN THE BODY WHICH CARRY CELLS AND
SUBSTANCES TO ALL ITS PARTS.
BLOOD VESSELS
THERE ARE THREE TYPES OF BLOOD VESSEL:



ARTERIES CARRY BLOOD AWAY FROM THE HEART STRAIGHT AFTER IT HAS BEEN
PUMPED. THIS MEANS IT IS UNDER HIGH PRESSURE. THE WALLS OF ARTERIES ARE
MADE OF THICK MUSCLE TO WITHSTAND THIS PRESSURE. THIS MUSCLE IS ALSO
ELASTIC TO ALLOW A PULSE OF BLOOD TO TRAVEL ALONG WHEN YOUR HEART
BEATS.
VEINS CARRY BLOOD BACK TO THE HEART. THIS BLOOD IS UNDER LOWER
PRESSURE BECAUSE SOME OF IT HAS BEEN LOST AS IT TRAVELLED AROUND YOUR
BODY. THE WALLS OF VEINS ARE MADE OF THINNER MUSCLE AND ARE LESS ELASTIC
THAN ARTERIES. BECAUSE THE BLOOD IS UNDER LOWER PRESSURE, ONE-WAY
VALVES IN YOUR VEINS STOP IT FLOWING BACKWARDS.
CAPILLARIES ARE THE TINY BLOOD VESSELS THAT BRANCH OUT INTO EVERY TISSUE
IN YOUR BODY CARRYING SUBSTANCES YOUR CELLS NEED LIKE OXYGEN AND
GLUCOSE FOR RESPIRATION AND FOR REMOVING WASTE PRODUCTS LIKE CARBON
DIOXIDE. THEY HAVE VERY THIN WALLS TO ALLOW THESE SUBSTANCES TO MOVE
BY DIFFUSION IN AND OUT OF YOUR CELLS. CAPILLARIES JOIN YOUR ARTERIES TO
YOUR VEINS.
THE HEART
THE HEART IS A LARGE MUSCULAR ORGAN WHICH PUMPS BLOOD TO THE LUNGS AND THEN THE
REST OF YOUR BODY. IT HAS FOUR CHAMBERS.
THE HEART'S FOUR CHAMBERS SHOWING THE MOVEMENT OF BLOOD WITHIN IT. THE HEART HAS
FOUR CHAMBERS AND A THICK MUSCULAR WALL
THE TWO TOP CHAMBERS ARE CALLED ATRIA (RIGHT ATRIUM AND LEFT ATRIUM) AND THE BOTTOM
CHAMBERS ARE CALLED VENTRICLES (RIGHT VENTRICLE AND LEFT VENTRICLE). THE ATRIA COLLECT
BLOOD AND THEN PUMP THEM TO THE VENTRICLES BELOW. THE VENTRICLES THEN PUMP THE
BLOOD TO THE BODY. IT LOOKS AS THOUGH THE VENTRICLES ARE BIGGER BUT THE FOUR
CHAMBERS INSIDE ARE THE SAME SIZE. IT IS THE MUSCULAR LINING OF THE VENTRICLES THAT ARE
BIGGER BECAUSE THEY HAVE TO PUMP THE BLOOD FURTHER THAN THE ATRIA.
DOUBLE CIRCULATORY SYSTEM
HUMANS HAVE A DOUBLE CIRCULATORY SYSTEM, WHICH MEANS THE BLOOD PASSES THROUGH
THE HEART TWICE ON EACH LOOP AROUND THE BODY. IT TRAVELS FROM THE HEART TO THE
LUNGS, TO THE HEART, TO THE REST OF THE BODY BEFORE RETURNING TO THE HEART. THIS IS
OFTEN CALLED A 'FIGURE OF EIGHT SYSTEM'.
BLOOD COMPONENETS
THERE ARE FOUR COMPONENTS - OR PARTS - OF THE BLOOD: RED BLOOD CELLS, WHITE BLOOD
CELLS, PLASMA AND PLATELETS. BLOOD CARRIES THINGS YOU NEED, LIKE OXYGEN AND GLUCOSE,
AND WASTE PRODUCTS, SUCH AS CARBON DIOXIDE, AROUND YOUR BODY.
COMPONENT FUNCTIONS
EACH COMPONENT HAS A FUNCTION.
COMPONENT
FUNCTION
RED BLOOD CELL
TO CARRY OXYGEN FROM THE LUNGS TO EVERY CELL IN THE REST OF THE BODY
COMPONENT
FUNCTION
WHITE BLOOD CELL
TO FIGHT INFECTION BY PATHOGENS AND STOP DISEASE
PLASMA
CARRIES THE BLOOD CELLS AND PLATELETS AROUND THE BODY
PLATELET
BROKEN DOWN PARTS OF CELLS THAT FORM SCABS
THERE ARE DIFFERENT AMOUNTS OF THE FOUR COMPONENTS IN THE BLOOD.
THE COMPONENTS OF THE BLOOD SHOWN AS PERCENTAGES
RED BLOOD CELLS
RED BLOOD CELLS ARE THE MOST NUMEROUS CELL IN THE BLOOD. IN ONE DROP OF BLOOD THERE
ARE AROUND 3-5 MILLION RED BLOOD CELLS. THEY ARE MADE IN BONE MARROW.
OXYGEN MOVES BY DIFFUSION INTO RED BLOOD CELLS IN THE LUNGS. THEY HAVE A CHEMICAL
INSIDE THEM CALLED HAEMOGLOBIN, A RED PIGMENT WHICH BINDS WITH THE OXYGEN TO CARRY
OXYGEN TO WHERE IT IS NEEDED FOR RESPIRATION. THIS REACTION IS REVERSED NEAR THE CELLS.
RED BLOOD CELLS DO NOT HAVE A NUCLEUS TO MAXIMISE THE OXYGEN THEY CAN CARRY. THEY
HAVE DIPS ON BOTH SIDES TO MAXIMISE THEIR SURFACE AREA TO ABSORB OXYGEN AS QUICKLY AS
POSSIBLE. THIS SHAPE IS CALLED BICONCAVE.
WHITE BLOOD CELLS
WHITE BLOOD CELLS FORM PART OF THE IMMUNE SYSTEM TO KEEP US SAFE FROM INFECTION AND
DISEASE. THERE ARE 10,000-20,000 WHITE BLOOD CELLS IN ONE DROP OF BLOOD, AND EVEN MORE
WHEN A PERSON IS ILL. THEY ARE MADE IN BONE MARROW.
THERE ARE TWO TYPES OF WHITE BLOOD CELL:


PHAGOCYTES WHICH SURROUND, ENGULF AND DESTROY PATHOGENS.
LYMPHOCYTES WHICH PRODUCE ANTIBODIES THAT STICK PATHOGENS TOGETHER. THIS
MAKES IT EASIER FOR PHAGOCYTES TO DESTROY THE PATHOGENS.
SCIENTISTS SAY THAT PHAGOCYTES ‘ENGULF’ PATHOGENS RATHER THAN ‘EAT’ THEM BECAUSE THEY
DO NOT HAVE A MOUTH.
PLASMA
PLASMA IS THE LIQUID THAT MAKES UP MORE THAN HALF OF THE BLOOD IN A HUMAN BODY. IT IS
MAINLY MADE OF WATER AND IS PALE YELLOW SO IS OFTEN CALLED ‘STRAW-COLOURED’.
IT CARRIES ALL THE PLATELETS AND RED AND WHITE BLOOD CELLS AROUND THE HUMAN BODY. IT
ALSO CARRIES HORMONES, DISSOLVED GLUCOSE FOR RESPIRATION, DISSOLVED SALTS
AND ENZYMES AROUND THE BODY. WASTE PRODUCTS LIKE CARBON DIOXIDE ARE ALSO
TRANSPORTED IN THE PLASMA.
PLATELETS
PLATELETS ARE SMALL, COLOURLESS FRAGMENTS OF CELLS THAT FORM SCABS TO STOP CUTS FROM
BLEEDING. THERE ARE SEVERAL HUNDRED THOUSAND PLATELETS IN EACH DROP OF BLOOD.
LIKE RED AND WHITE BLOOD CELLS, PLATELETS ARE MADE IN BONE MARROW.
SKELETAL SYSTEM
THE SKELETON ALLOWS MOVEMENT, PROVIDES SUPPORT AND PROTECTION FOR VITAL ORGANS
AND MAKES BLOOD CELLS. SKELETAL MUSCLES MOVE THE BONES IN THE BODY.
SKELETAL AND MUSCULAR SYSTEMS
THE SKELETAL SYSTEM IS MADE FROM BONES AND JOINTS.


THE FEMUR BONE IN THE THIGH IS THE LONGEST AND STRONGEST BONE IN THE
BODY.
THE SMALLEST BONES IN THE BODY ARE CALLED THE OSSICLES IN THE EAR.
BONE IS A LIVING TISSUE WITH A BLOOD SUPPLY. IT IS CONSTANTLY BEING DISSOLVED AND FORMED
AND IT CAN REPAIR ITSELF IF A BONE IS BROKEN. CALCIUM IS IMPORTANT FOR THIS PROCESS.
BONES WORK WITH MUSCLES AND TENDONS TO ALLOW THE BODY TO MOVE.
FUNCTION OF THE SKELETON
THE SKELETON HAS FOUR MAIN FUNCTIONS:




TO SUPPORT THE BODY
TO PROTECT SOME OF THE VITAL ORGANS OF THE BODY
TO HELP THE BODY MOVE
TO MAKE BLOOD CELLS
SUPPORT
THE SKELETON SUPPORTS THE BODY.
THE SPINAL CORD IS SURROUNDED BY VERTEBRA. MOST PEOPLE ARE BORN WITH 33 OF THESE BUT
ADULTS USUALLY HAVE 24 BECAUSE SOME JOIN TOGETHER NATURALLY AS THE BODY GROWS.
WITHOUT THESE BONES PEOPLE WOULD NOT BE ABLE TO SIT UPRIGHT. THE MAJOR BONES IN THE
LEGS ARE THE FEMUR, FIBULA AND TIBIA. THESE ALLOW A PERSON TO STAND UPRIGHT.
PROTECTION
THE BONES PROTECT THE VITAL ORGANS:



THE SKULL PROTECTS THE BRAIN
THE VERTEBRAE PROTECT THE SPINAL CORD
THE RIBCAGE PROTECTS THE HEART, LUNGS AND LIVER
X-RAY OF THE RIBS - A CAGE-LIKE STRUCTURE WHICH PROTECTS THE ORGANS INSIDE
MOVEMENT
SOME BONES IN THE SKELETON ARE JOINED RIGIDLY TOGETHER AND CANNOT MOVE AGAINST EACH
OTHER. BONES IN THE SKULL ARE JOINED IN THIS WAY. OTHER BONES ARE JOINED TO EACH OTHER
BY FLEXIBLE JOINTS. THE VERTEBRAE HAVE LIMITED MOVEMENT, BUT THE SHOULDERS, ELBOWS
AND KNEES ARE JOINTS THAT ALLOW MORE MOVEMENT.
MUSCLES ARE ATTACHED TO BONES BY TENDONS. SKELETAL MUSCLES CONTRACT AND RELAX TO
MOVE BONES.
THERE ARE DIFFERENT KINDS OF BLOOD CELLS, INCLUDING:


RED BLOOD CELLS, WHICH CARRY OXYGEN AROUND THE BODY IN THE BLOOD
WHITE BLOOD CELLS, WHICH ARE INVOLVED IN DESTROYING HARMFUL
MICROORGANISMS IN THE BODY
THESE CELLS ARE MADE IN THE BONE MARROW. THIS IS SOFT TISSUE INSIDE OUR LARGER BONES
WHICH IS PROTECTED BY THE HARD PART OF THE BONE WHICH SURROUNDS IT.
RESPIRATORY SYSTEM
THE GAS EXCHANGE SYSTEM IS RESPONSIBLE FOR GETTING OXYGEN INTO THE BLOOD AND
REMOVING CARBON DIOXIDE AS A PERSON BREATHES. BREATHING IS ALSO CALLED 'VENTILATION'
AND IS THE MOVEMENT OF GASES INTO AND OUT FROM THE LUNGS. EXERCISE, SMOKING AND
ASTHMA ARE ALL FACTORS THAT CAN AFFECT THE GAS EXCHANGE SYSTEM. THERE ARE THREE MAIN
GASES IN AIR THAT ARE TAKEN IN AND REMOVED FROM THE BODY. THESE ARE OXYGEN, NITROGEN
AND CARBON DIOXIDE. GAS EXCHANGE IS THE ‘SWAPPING’ OF GASSES - ABSORBING OXYGEN INTO
THE BLOOD AND REMOVING CARBON DIOXIDE FROM THE BLOOD. DIFFUSION MOVES OXYGEN OUT
OF THE ALVEOLI AND INTO THE BLOOD.
THE GAS EXCHANGE SYSTEM
THE PROCESS OF BREATHING IS CALLED VENTILATION. BREATHING IN IS CALLED INHALING, AND
BREATHING OUT IS EXHALING.
WHEN YOU INHALE, YOUR DIAPHRAGM MUSCLE CONTRACTS AND MOVES DOWNWARDS, AND THE
INTERCOSTAL MUSCLES CONTRACT AND MOVE THE RIBS UPWARDS AND OUTWARDS. THIS
INCREASES THE VOLUME OF THE LUNGS, WHICH REDUCES THE PRESSURE INSIDE AND SO AIR
MOVES INTO THE LUNGS TO EQUALISE IT. AIR THAT IS RICH IN OXYGEN MOVES INTO THE GAS
EXCHANGE SYSTEM AND THEN THE BODY WHEN YOU BREATHE IN.
WHEN YOU EXHALE, OUR DIAPHRAGM MUSCLE RELAXES AND MOVES UPWARDS, AND THE
INTERCOSTAL MUSCLES RELAX AND MOVE DOWNWARDS AND INWARDS. THIS REDUCES THE
VOLUME OF THE LUNGS, WHICH FORCES AIR OUTWARDS. AIR WITH MORE CARBON DIOXIDE IS
THEN REMOVED WHEN YOU BREATHE OUT.
THE GAS EXCHANGE SYSTEM IS MADE FROM KEY PARTS, EACH OF WHICH HAS A DIFFERENT
FUNCTION.
PART OF THE GAS
EXCHANGE SYSTEM
FUNCTION
TRACHEA
THIS IS ALSO CALLED THE WINDPIPE. THIS TUBE RUNS FROM THE MOUTH, DOWN
THE THROAT TOWARDS THE LUNGS. IT IS LINED WITH RINGS
OF CARTILAGE WHICH KEEP IT OPEN AT ALL TIMES.
BRONCHUS
THE TRACHEA SPLITS INTO A LEFT AND RIGHT BRONCHUS (PLURAL: BRONCHI),
EACH LEADS TO A LUNG.
BRONCHIOLE
EACH BRONCHUS SPLITS AGAIN AND AGAIN INTO THOUSANDS OF SMALLER
TUBES CALLED BRONCHIOLES WHICH TAKE THE AIR DEEPER INTO THE LUNGS.
ALVEOLI
AT THE ENDS OF BRONCHIOLES ARE TINY AIR SACS CALLED ALVEOLI. HERE
OXYGEN MOVES INTO THE BLOOD AND CARBON DIOXIDE MOVES OUT.
INTERCOSTAL
MUSCLES
THESE MUSCLES RUN BETWEEN THE RIBS AND FORM THE CHEST WALL. THEY
CONTRACT AND RELAX WITH THE DIAPHRAGM WHEN A PERSON BREATHES.
DIAPHRAGM
THE DIAPHRAGM IS A DOME-SHAPED, FLAT SHEET OF MUSCLE UNDER THE
LUNGS. IT CONTRACTS AND RELAXES WITH THE INTERCOSTAL MUSCLES DURING
BREATHING.
THE HUMAN GAS EXCHANGE SYSTEM
THE ALVEOLI IN DETAIL
ALVEOLI ARE THE TINY AIR SACS FOUND AT THE END OF BRONCHIOLES IN YOUR LUNGS. GAS
EXCHANGE OCCURS HERE. OXYGEN MOVES INTO THE BLOOD AND CARBON DIOXIDE IS REMOVED.
THIS OXYGEN IS NEEDED FOR RESPIRATION TO RELEASE ENERGY FROM GLUCOSE WHICH HAS BEEN
OBTAINED FROM FOOD. CARBON DIOXIDE IS A WASTE PRODUCT IN THIS PROCESS AND MUST BE
REMOVED.
SOME WATER VAPOUR IS ALSO LOST FROM THE SURFACE OF THE ALVEOLI INTO THE LUNGS - WE
CAN SEE THIS CONDENSING WHEN WE BREATHE OUT ON COLD DAYS.
ALVEOLI HAVE THE FOLLOWING KEY FEATURES TO MAXIMISE GAS EXCHANGE:



A HUGE COMBINED SURFACE AREA
MOIST, THIN WALLS TO MAXIMISE DIFFUSION.
MILLIONS OF TINY BLOOD VESSELS CALLED CAPILLARIES JUST BEHIND THESE WALLS.
VENTILATION
AIR GETS INTO AND OUT OF THE BODY BY THE PHYSICAL PROCESS OF BREATHING, ALSO CALLED
VENTILATION. THIS PROCESS INVOLVES MOVEMENTS OF THE RIBS, INTERCOSTAL MUSCLES AND
DIAPHRAGM TO MOVE AIR INTO AND OUT OF THE LUNGS.
THESE ARE THE CHANGES INVOLVED DURING INHALATION AND EXHALATION.
INHALING
EXHALING
DIAPHRAGM
CONTRACTS AND MOVES DOWNWARDS RELAXES AND MOVES UPWARDS
INTERCOSTAL
MUSCLES
CONTRACT, MOVING THE RIBS
UPWARDS AND OUTWARDS
RELAX, LETTING THE RIBS MOVE
DOWNWARDS AND INWARDS
VOLUME OF RIBCAGE INCREASES
DECREASES
PRESSURE INSIDE THE DECREASES BELOW ATMOSPHERIC
CHEST
PRESSURE
INCREASES ABOVE ATMOSPHERIC
PRESSURE
MOVEMENT OF AIR
MOVES OUT OF THE LUNGS
MOVES INTO THE LUNGS
RESPIRATION
THERE ARE 2 TYPES OF RESPIRATION NAMELY:


AEROBIC RESPIRATION
ANAEROBIC RESPIRATION
AEROBIC RESPIRATION
ANAEROBIC RESPIRATION
PLANTS
PHOTOSYNTHESIS
PHOTOSYNTHESIS IS THE PROCESS BY WHICH PLANTS MAKE CARBOHYDRATE AS FOOD. THE
CARBOHYDRATE IS STORED IN THE FORM OF STARCH.
STARCH IN LEAVES
STARCH IS A STORE OF ENERGY. IT IS A CARBOHYDRATE AND FORMS COLOURLESS GRAINS IN THE
CYTOPLASM OF LEAF CELLS IN THE PALISADE AND SPONGY MESOPHYLL LAYERS.
TEST FOR STARCH IN LEAVES
A BEAKER OF WATER IS BOILED AND THE HEAT SOURCE IS TURNED OF
THE LEAF IS HELD IN A PAIR OF FORCEPS AND DIPPED IN THE HOT WATER FOR ABOUT 30 SECONDS.
THIS KILLS THE CELLS AND PREVENTS ANY FURTHER REACTIONS TAKING PLACE IN THEM. IT ALSO
MAKES IT EASIER FOR IODINE SOLUTION TO ENTER THE CELLS IN STEP 5.
THE LEAF IS THEN PLACED IN THE BOTTOM OF A TEST TUBE AND COVERED WITH ETHANOL. THE
TEST TUBE IS PLACED IN THE BEAKER OF HOT WATER. ALCOHOL HAS A BOILING POINT THAT IS
BELOW THAT OF THE HOT WATER AND AS IT BOILS IT DISSOLVES MOST OF THE CHLOROPHYLL IN
THE CELLS AND MAKES THE STARCH GRAINS EASIER TO SEE WHEN THEY ARE STAINED WITH IODINE.
THE ALCOHOL IN THE TEST TUBE IS POURED INTO A SECOND BEAKER AND THE LEAF, WHICH IS NOW
BRITTLE, IS REMOVED WITH FORCEPS AND DIPPED INTO THE HOT WATER AGAIN TO MAKE IT
SOFTER AND EASIER TO HANDLE IN THE NEXT STEP.
THE SOFT LEAF IS THEN SPREAD OUT ON A WHITE TILE AND DROPS OF IODINE ARE RELEASED ONTO
ITS SURFACE. THE IODINE SOLUTION ENTERS THE CELLS AND IF STARCH GRAINS ARE PRESENT THEY
ARE STAINED BLUE BLACK.
CONSTRUCTING THE EQUATION FOR PHOTOSYNHESIS
WATER
WATER IS ESSENTIAL FOR LIFE. IF PLANTS DON’T HAVE WATER, THEY DIE.
WATER IS DRAWN INTO THE PLANT ROOTS FROM THE SOIL AND IS CARRIED ALONG MICROSCOPIC
TUBES IN THE XYLEM TISSUE FROM THE ROOT, INTO THE STEM AND THEN TO ALL THE OTHER PARTS
OF THE PLANT. WHEN IT REACHES THE LEAVES IT TAKES PART IN THE MAKING OF FOOD.
THE FIRST STEP IN BUILDING UP THE EQUATION FOR PHOTOSYNTHESIS BEGINS WITH WATER, AS
SHOWN HERE:
WATER +
CARBON DIOXIDE AND STARCH PRODUCTION
POLLINATION
INSECT-POLLINATION OF FLOWERING PLANTS IS RESPONSIBLE FOR THE MAJORITY OF THE WORLD’S
FLOWERING DIVERSITY AND IS AN ESSENTIAL PART OF PLANT REPRODUCTION. FLOWERS HAVE
BRIGHT COLOURS, SMELLS AND NECTAR WHICH ENCOURAGE POLLINATORS TO PAY THEM A VISIT.
HONEYBEES ALONG WITH 1,500 OTHER INSECT SPECIES POLLINATE PLANTS IN THE UK.
FLOWER STRUCTURE
FLOWERING PLANTS REPRODUCE SEXUALLY THROUGH A PROCESS CALLED POLLINATION. THE
FLOWERS CONTAIN MALE SEX ORGANS CALLED STAMENS AND FEMALE SEX ORGANS
CALLED PISTILS. THE MALE AND FEMALE SEX CELLS PRODUCED FROM THE MALE AND FEMALE SEX
ORGANS MUST MEET FOR REPRODUCTION TO BEGIN.
'FLOWERING PLANTS' INCLUDES FRUIT PLANTS AND TREES WHICH PRODUCE FLOWERS AS WELL AS
FRUIT.
THE REPRODUCTIVE PARTS OF A FLOWER


THE MALE GAMETES ARE CONTAINED IN THE POLLEN GRAINS PRODUCED IN
THE ANTHER.
THE FEMALE GAMETES (EGG CELLS OR OVA) ARE PRODUCED IN THE OVULE FOUND
IN THE OVARY.
POLLINATION
POLLINATION IS THE ACT OF TRANSFERRING POLLEN GRAINS FROM THE MALE ANTHER OF A
FLOWER TO THE FEMALE STIGMA. THE AIM OF MOST LIVING ORGANISMS, INCLUDING PLANTS, IS TO
PRODUCE OFFSPRING FOR THE NEXT GENERATION. ONE OF THE WAYS THAT PLANTS CAN PRODUCE
OFFSPRING IS BY MAKING SEEDS. SEEDS CONTAIN THE NUTRITION AND ALL THE GENETIC
INSTRUCTIONS TO GROW INTO AN ADULT PLANT.
THERE ARE TWO TYPES OF POLLINATION:
SELF-POLLINATION: THE POLLEN GRAIN LANDS ON THE SAME FLOWER IT ORIGINATED FROM.
CROSS-POLLINATION: THE POLLEN GRAIN LANDS ON A DIFFERENT FLOWER TO THE ONE IT
ORIGINATED FROM.
WIND AND INSECT POLLINATION
AS PLANTS CANNOT MOVE LIKE ANIMALS THEY MUST ADOPT A DIFFERENT METHOD OF
TRANSFERRING THESE POLLEN GRAINS.


WIND-POLLINATED PLANTS LET THEIR POLLEN BLOW IN THE WIND AND HOPE THAT
THEIR POLLEN GRAINS REACH ANOTHER PLANT FOR POLLINATION.
INSECT-POLLINATED PLANTS USE INSECTS AND OTHER ANIMALS TO CARRY THEIR
POLLEN GRAINS TO OTHER PLANTS.
THE VAST MAJORITY OF PLANTS DEPEND ON ANIMALS TO TRANSFER THE POLLEN FOR THEM.
'INSECT-POLLINATED' INCLUDES PLANTS WHICH ARE POLLINATED BY BIRDS AND OTHER SMALL
ANIMALS.
THIS GRASS IS POLLINATED BY THE WIND; THE FLOWER IS BEING POLLINATED BY THE
HUMMINGBIRD
INSECT-POLLINATED FLOWERS ARE DIFFERENT IN STRUCTURE FROM WIND-POLLINATED FLOWERS.
FEATURE
INSECT-POLLINATED
WIND-POLLINATED
POSITION OF
STAMENS
ENCLOSED WITHIN THE FLOWER SO INSECTS EXPOSED SO THAT WIND CAN EASILY
MUST MAKE CONTACT
BLOW POLLEN AWAY
POSITION OF
STIGMA
ENCLOSED
EXPOSED
TYPE OF STIGMA
STICKY, SO THAT POLLEN ATTACHES TO
INSECTS
FEATHERY, TO CATCH POLLEN BLOWN
FROM WIND
COLOUR OF
PETALS
BRIGHTLY COLOURED TO ATTRACT INSECTS
DULL, USUALLY GREEN
NECTARIES
PRESENT AS REWARD FOR INSECTS
ABSENT
POLLEN GRAINS
LARGER, STICKY
SMALLER, SMOOTH, INFLATE
CLASSIFICATION AND VARIATION
MICROORGANISMS
GROUP
FUNGI KINGDOM
MONERA KINGDOM
PROTOCTISTA
KINGDOM
VIRUSES
FEATURES
HAVE SPORES, AND FEEDING THREADS
CALLED HYPHAE
ONE CELL BODY WITHOUT A NUCLEUS
ONE CELL BODY WITH A NUCLEUS
EXAMPLES
YEAST, MUSHROOM
NO CELL STRUCTURE
INFLUENZA VIRUS, HIV
BACTERIA, BLUE-GREEN ALGAE
AMOEBA, CILIATES
THE PLANT KINGDOM
GROUP
ALGAE
LIVERWORTS AND
MOSSES
FERNS
CONIFERS
FLOWERING PLANTS
FEATURES
DO NOT HAVE ROOTS, STEMS OR
LEAVES
DO NOT HAVE TRUE ROOTS, HAVE
SPORES
ROOTS, STEMS, FRONDS AND SPORES
ROOTS, WOODY STEM, CONES, SEEDS
ROOTS, STEMS, LEAVES, FLOWERS,
SEEDS SOME ARE WOODY AND
OTHERS NON-WOODY
EXAMPLE
GREEN SLIME, SEAWEEDS
SPHAGNUM MOSS, COMMON
OR UMBRELLA LIVERWORT
FIDDLE HEAD FERNS
FIR, PINE
DAISY, MANGO,MINT, OAK,
PINEAPPLE, FIG, CHESTNUT,
DANDELION
THE ANIMAL KINGDOM
INVERTEBRATES
GROUP
JELLYFISH
FEATURES
SOFT BODY, TENTACLES AT
ONE END ROUND THE
MOUTH
VERY THIN, FLAT BODY
CYLINDRICAL BODIES NOT
DIVIDED INTO RINGS
SMALL CYLINDRICAL BODIES
NOT DIVIDE
JOINTED LEGS
FLATWORMS
ANNELID
WORMS
NEMATODE
WORMS
ARTHROPODS
MOLLUSCS
SOFT BODY WITH SHELL
(WHICH MIGHT BE INSIDE)
SPINY SKIN, ARMS
(STARFISH) OR GLOBE
SHAPED (SEA URCHINS)
ECHINODERMS
EXAMPLES
BOX JELLYFISH, SEA ANEMONE, CORAL (MAKE
HARD CASING)
FLUKES, TAPEWORMS
EARTHWORMS, LEECH, RAGWORM,
FANWORM
HOOKWORM,PINWORM
INSECTS, SPIDERS, SCORPIONS, CRUSTACEANS
(SHRIMP AND CRAB), CENTIPEDES, MILLIPEDES
SNAILS, SLUGS, OCTOPUS, MUSSELS, SQUID,
SCALLOPS, LIMPETS
BRITTLE STAR, SEA CUCUMBER, SEA LILY
VERTEBRATES
GROUP
FISH
AMPHIBIANS
REPTILES
BIRDS
MAMMALS
FEATURES
SCALES, FINS
SMOOTH OR WARTY SKIN, TADPOLE STAGE
SKIN COVERED IN DRY SCALES
FEATHERS, BEAKS
FUR, GIVE MILK TO YOUNG
EXAMPLES
BARRACUDA, SHARK
FROGS, TOADS, SALAMANDERS
SNAKES, TURTLES, LIZARDS
HUMMINGBIRD, EAGLE
MOUSE, MOLE, LION