Year 10 Science 20121 Biology Year 10 Human Biology
Slide 2
The structure and functions of the human (as an animal)
systems: skeletal, digestive, circulatory, respiratory. Year 10
Science 20122 All vertebrates share the same basic body plan, with
tissues and organs functioning in a similar manner. We focus on the
human body, studying structure (anatomy) and function
(physiology).
Slide 3
Year 10 Science 20123 The structure and functions of the human
(as an animal) systems: skeletal, digestive, circulatory,
respiratory. Animals are made of complex systems of cells, which
must be able to perform all of lifes processes and work in a
coordinated fashion to maintain homeostasis (a stable internal
environment). During a humans early development, groups of cells
specialize into three fundamental embryonic layers. These embryonic
layers differentiate into a number of specialized cells and
tissues. Tissues are groups of cells similar in structure and
function.
Slide 4
Year 10 Science 20124 The structure and functions of the human
(as an animal) systems: skeletal, digestive, circulatory,
respiratory. Different tissues functioning together for a common
purpose are called organs (eg, stomach, kidney, lung, heart). Organ
systems are composed of individual organs working together to
accomplish a coordinated activity. For example, the heart, veins
and arteries all play a role in circulation.
Slide 5
Year 10 Science 2012 The Human skeletal system. The human
skeletal system is an internal skeleton that serves as a framework
for the body. This framework consists of many individual bones and
cartilages. This also includes ligaments and the tendons which hold
bones to each other and to muscles that contract and cause the
bones to move. The adult human skeleton contains more than 200
bones. The skeleton also provides mechanical protection for many of
the body's internal organs, reducing risk of injury to them,
storage of minerals and production of blood cells.
Slide 6
The main bones in the Human skeletal system. The main bones of
the human skeleton are divided into two groups. The axial skeleton
is the central group of bones based around the spinal (vertebral)
column. The appendicular skeleton consists of bones or groups of
bones which hang off the axial skeleton.
Slide 7
7 The Human skeletal system. The main bones of the human
skeleton are: The Skull Shoulder girdle - clavicle and scapula Arm
- humerus, radius and ulna Hand - Carpals, Metacarpals and
Phalanges Chest - Sternum and Ribs Spine - vertebrae, Sacrum (5
fused or stuck together bones) and Coccyx (the tiny bit at the
bottom of the spine). Pelvic girdle - Ilium, Pubis and Ischium. Leg
- Femur, Tibia and Fibula Ankle - Talus and calcaneus Foot -
Tarsals, Metatarsals and Phalanges
Slide 8
A joint occurs where two bones meet. Movement of the skeleton
occurs at the joints where two or more bones meet. There are
different categories of joints. Freely movable, or synovial, joints
allow a range of movement determined by the structure of the joint.
Examples of movable joints are the ball and socket (shoulder),
hinge (elbow), pivot (between the skull and neck) and ellipsoidal
joint (hand and arm). Ligaments are inelastic connective tissues
which hold bones together in a joint.
Slide 9
Year 10 Science 20129 The structure of the skeleton and muscles
of the human arm The muscles are attached to the bones by tendons.
When the muscles contract they shorten and move the bones at the
joints. All of the bones in the skeleton require muscles in order
to move them. The muscles are attached by the nervous system to the
brain which controls their movement either voluntary or
automatically when required.
Slide 10
The antagonistic muscles and bones act together to flex or
extend the arm Muscles can contract, but are not designed to
actively lengthen, so they are arranged as opposing antagonistic
pairs. As one muscle shortens, another is stretched and vice versa.
The contacting muscles move the bones they are attached to.
Slide 11
Year 10 Science 201211 The digestive system The digestive
system converts foods to simple substances that can be absorbed and
used by the cells of the body. It is composed of the mouth,
pharynx, oesophagus, stomach, small intestine and large intestine
and is aided by several accessory organs (liver, gall bladder, and
pancreas).
Slide 12
12 Digestion breaks large molecules of food into small ones,
which can then pass through the wall of the gut into the blood.
Ingestion How we take in food using our mouths Digestion Breaking
food into smaller pieces Absorption Taking food into the blood
Egestion Removal of food from the anus anus Year 10 Science
201212
Slide 13
Year 10 Science 201213 1.Canine and incisors teeth rip, tear
and bite pieces of the food. 2.Suitable sized pieces of food enter
the mouth. 3.Pre-molars and molars grind the food into smaller
pieces. 4.Saliva is mixed with the food from the saliva glands.
5.Enzymes in the saliva start breaking down (digesting) the food.
6.Lumps of chewed food are swallowed down the esophagus. 7.Food
moves into the stomach GazeSJ Ingestion is how we take in food
using our mouths.
Slide 14
Year 10 Science 201214 The internal structure of a human tooth.
The tooth has a hard covering of enamel which protects it and gives
it strength to bite and chew food. When tooth decay occurs the
enamel is eaten away by bacteria and tooth pain occurs because acid
and infection reach the dentine and tooth nerves. The tooth is
embedded into the jaw bone by the roots which secure it.
Slide 15
Year 10 Science 201215 How the different types of human teeth
are used when eating. The incisors at the front of the mouth are
used to bite pieces of food. The canines are bigger and used to
tear food. The bicuspids (also called premolars) and the molars at
the back of the mouth are used to chew food. There are 32 teeth in
a full set of adult teeth.
Slide 16
Year 10 Science 201216 How the different types of Animal
(carnivores) teeth are used when eating. Tiger carnivorous cat
Alligator carnivorous reptile Otter carnivorous fish eater Sharp
pointed canines GazeSJ
Slide 17
17 How the different types of Animal (Herbivores) teeth are
used when eating. Horse grazing herbivore Grey kangaroo Australian
grazing marsupial Rabbit grazing rodent Grinding molars Chisel-like
incisors No canines GazeSJ
Slide 18
Year 10 Science 2012 18 How the different types of Animal
(omnivores) teeth are used when eating. Badger eats more animals
than plants. Flattened molars to grind plants Human eats more
plants than animals Canines much smaller GazeSJ
Slide 19
19 How the different types of Animal teeth (specialist) are
used when eating. Baleen whales The specialized filter-feeding
mechanism of baleen whales enables them to feed low on the food
chain by primarily eating zooplankton and schooling fishes. Giant
Anteater sucks up ants with long tongue and has no need for teeth
at all. GazeSJ
Slide 20
Year 10 Science 201220 The gut is a coiled tube and is the site
of digestion and absorption. The second stage in food processing is
digestion Definition Digestion Breaking food into smaller pieces
Once food is ingested it moves down into the oesophagus and then
into the stomach Definition Oesophagus The tube that food travels
from the mouth to the stomach through Definition Stomach Organ from
the digestive system that digests food GazeSJ
Slide 21
21 The gut is a coiled tube and is the site of digestion and
absorption. The third stage in food processing is absorption
Definition Absorption Taking food into the blood This absorption
occurs in the small intestine which the food moves into from the
stomach and water absorption occurs in the large intestine
Definition Small Intestine Organ from the digestive system that
absorbs food into the blood Definition Large intestine Organ from
the digestive system that absorbs water from waste food Blood
containing the absorbed food then moves to the liver to be further
processed Definition Liver Organ from the digestive system that
stores and distributes food GazeSJ
Slide 22
Year 10 Science 201222 The main structure of the digestive
system and its associated organs - oesophagus. The oesophagus is
like a stretchy pipe that's about 25 centimeters long. It moves
food from the back of your throat to your stomach. When you swallow
a small ball of mushed-up food or liquids, a special flap called
the epiglottis closes over the opening of your windpipe to make
sure the food enters the oesophagus and not the windpipe. Once food
has entered the oesophagus muscles in the walls move in a wavy way
to slowly squeeze the food through the oesophagus (peristalsis) and
into the stomach.
Slide 23
Year 10 Science 201223 The main structure of the digestive
system and its associated organs stomach. Your stomach is attached
to the end of the oesophagus. It has three important functions:
>to store the food you've eaten >to break down the food into
a liquid mixture >to slowly empty that liquid mixture into the
small intestine The stomach mixes, churns and mashes together all
the small pieces of food into smaller and smaller pieces called
digestion. It does this with help from the strong muscles in the
walls of the stomach and gastric juices that also come from the
stomach's walls. In addition to breaking down food, gastric juices
also help kill bacteria that might be in the eaten food.
Slide 24
24 The main structure of the digestive system and its
associated organs - small and large intestine. The small intestine
is a long tube around 3.5 to 5 centimeters around, which connects
from beneath your stomach and is about 7 meters long. The small
intestine breaks down the food mixture even more so your body can
absorb all the vitamins, minerals, proteins, carbohydrates, and
fats. Food may spend as long as 4 hours in the small intestine and
will become a very thin, watery mixture which can pass from the
intestine into the blood. Small intestine
Slide 25
25 The small intestine is the site of absorption of the
products of digestion. The walls of the small intestine are covered
in protruding villi which increase the surface area and provide
close contact for capillaries to absorb small food particles
through the wall.
Slide 26
Year 10 Science 201226 The main structure of the digestive
system and its associated organs - small and large intestine. The
large intestine is about 7 to 10 centimeters, which is wider than
the small intestine from which it joins on. It would measure about
1.5 meters long spread out. Most of the nutrients have already been
removed from the food mixture before it enters but there is waste
and water left over. Before it leaves the large intestine, it
passes through the part called the colon where the body is able to
absorb the water and some minerals into the blood.
Slide 27
27 The main structure of the digestive system and its
associated organs Pancreas, gall bladder and liver. These organs
send different juices to the first part of the small intestine.
These juices help to digest food and allow the body to absorb
nutrients. The pancreas makes enzymes that help the body digest
fats and protein. Enzymes from the liver called bile helps to
absorb fats into the bloodstream. The gallbladder serves as a
warehouse for bile, storing it until the body needs it.
Slide 28
Year 10 Science 201228 The main structure of the digestive
system and its associated organs pancreas, gall bladder and liver.
The nutrient-rich blood comes directly to the liver from the small
intestine for processing. The liver filters out harmful substances
or wastes, turning some of the waste into more bile. The liver
sorts how many nutrients will be distributed to the body, and how
many will stay behind in storage. The liver stores certain vitamins
and a type of sugar your body uses for energy.
Slide 29
Year 10 Science 201229 The main structure of the digestive
system and its associated organs rectum and anus. The final stage
of food processing is egestion, where the waste food that hasnt
been absorbed is moved through the rectum and out of the body
through the Anus. Definition Egestion Removal of wastes from the
anus Definition Anus part of the digestive system through which
wastes exit the body
Slide 30
30 There are four main food groups Carbohydrates >supply
instant energy >include sugar and starches >are supplied by
fruit (sugars) or by cereals (starches) Lipids >act as energy
stores >include fats and oils >are energy rich >are made
of fatty acids Proteins >are used for growth and repair >are
found in meat and eggs >are made of amino acid chains Minerals
and Vitamins >body needs them in small amounts >found in many
foods >non-organic substances GazeSJ The food we eat is divided
into four main groups
Slide 31
Year 10 Science 201231 Lipids present in fats and oils Some of
the food rubbed into filter paper. Remove food and allow to dry A
grease spot is left where the food was rubbed in if lipid was
present Protein present in meat and eggs Sodium hydroxide solution
Broken up food particles Add benedicts solution Mixture turns
purple if protein present GazeSJ We use tests to determine which
type of food is present.
Slide 32
Year 10 Science 201232 Starch present in cereals Place a few
drops of iodine on the food Food will turn black if starch is
present Glucose type of sugar Add Benedicts solution Broken up food
particles in water Heat mixture gently Mixture turns orange if
glucose present GazeSJ We use tests to determine which type of food
is present.
Slide 33
Year 10 Science 201233 The structure of the circulatory system
consists of blood, blood vessels and the heart. The function of the
circulatory system is to be the bodys transportation system, moving
oxygen, carbon dioxide, nutrients, wastes, hormones, vitamins,
minerals and water throughout the body. It also aids in regulation
of temperature. The circulatory system
Slide 34
Year 10 Science 201234 The external and internal structure of
the mammalian heart and its function. The mammal has a four
chambered heart with full division between the ventricles. This
means there is no mixing of the oxygenated and deoxygenated blood.
It contains valves, and heart beat is controlled by the nervous
system pacemaker.
Slide 35
Year 10 Science 201235 The external and internal structure of
the mammalian heart and its function. The function of the
Circulatory system must: >ensure delivery of blood to all
tissues >adapt so that blood flow can be controlled and changed
to individual tissues or the body as a whole >convert a
pulsating blood flow in the arteries into a steady flow in the
capillaries to allow optimum diffusion to and from the cells
>return blood to the heart
Slide 36
36 Arteries carry blood away from the heart, veins carry blood
towards the heart. The vascular system is composed of arteries,
arterioles, capillaries, venules and veins. The structure of the
vessels in the different parts of the vascular system varies and
the differences relate directly to the function of each type of
vessel.
Slide 37
37 Arteries carry blood away from the heart, veins carry blood
towards the heart. There are three main types of blood vessels:
>arteries, which carry blood away from the heart at relatively
high pressure. >veins, which carry blood back to the heart at
relatively low pressure. >capillaries which provide the link
between the arterial and venous blood vessels Arteries have thick
muscular and elastic walls to accommodate the high blood pressure
of the blood leaving the heart. Veins have thinner, non- muscular
walls to accommodate the lower blood pressure of the blood
returning to the heart. Capillaries are only one cell thick.
Slide 38
Year 10 Science 201238 Arteries carry blood away from the
heart, veins carry blood towards the heart. The Arteries and veins
have different structures because they have different functions
ArteryVein Direction of flow in relation to heart Blood Flows from
the heartBlood flows into the heart Pressure in the vessels High
pressureLow pressure Structure of walls Thick and muscular to
handle the high blood pressure. Thin and can stretch with changing
volumes of blood Other structures Contains valves to prevent back
flow of blood
Slide 39
Arteries carry blood away from the heart, veins carry blood
towards the heart. Circulatory system A Deoxygenated blood enters
the right atrium of the heart via the vena cava. B Deoxygenated
blood is pumped from the right ventricle, via the pulmonary artery,
to the lungs. C In the lungs, blood picks up oxygen and gets rid of
carbon dioxide. D Oxygenated blood travels back to the heart in the
pulmonary vein. E Oxygenated blood is pumped to vital organs and
the whole body from the left ventricle, via the aorta. F Digested
food is absorbed by blood through the walls of the small intestine.
G Digested food is processed and stored in the liver. H Waste
products (urea, water, salts etc.) are removed from the blood in
the kidneys. I Blood supplies the rest of the body with food and
oxygen. It carries away waste products.
Slide 40
Year 10 Science 201240 Capillaries link arteries with veins and
are the sites of exchange with the tissues. Arteries divide into
smaller arterioles around targeted tissues. The arterioles divide
once more into smaller capillaries which are only one cell thick.
Nutrients and O2 diffuse across the membranes of the capillaries
from the blood to the cell supplied from high to low concentration.
Waste products, such as CO2, will diffuse from the cell into the
capillary near the venule end. The venules rejoin into veins and
waste product contained within the blood will be pumped back to the
heart.
Slide 41
Year 10 Science 201241 Blood consists of fluid (serum)
containing cells white blood cells, red blood cells and platelets.
White blood cells (leucocytes) some produce antibodies to tag
foreign and harmful objects, others surround and eat tagged
objects. White blood cells prevent infection becoming established.
Make up the immunity system. Cells contain nucleus. Red Blood cells
(erythrocytes) contain haemoglobin, a pigment which binds to oxygen
molecules and carries it through the circulatory system. They
contain no nucleus. Platelets they collect where there is a hole in
the blood vessels and stop the unwanted flow of blood by
clotting.
Slide 42
Year 10 Science 201242 Red blood cells carry oxygen, attached
to haemoglobin, around the body of a mammal. Mammalian red blood
cells (erythrocytes) dispose their nuclei and cell organelles when
they are mature in order to provide more space for haemoglobin
(oxygen carrying pigment). Because the cells have no nucleus or
organelles, they cannot produce any RNA, and therefore they cannot
divide or repair themselves. They are constantly replaced by new
red blood cells. Red blood cells are biconcave disks and this shape
optimises the cell for the exchange of oxygen in the lungs. The red
blood cells are flexible so they can fit through tiny capillaries,
where they release their oxygen to cells.
Slide 43
Year 10 Science 201243 Plasma transports glucose, carbon
dioxide, urea and hormones. Plasma carries dissolved molecules
required by the body to each cell and waste products like carbon
dioxide and urea out of the body. Plasma also carries a large
number of important proteins. Albumin, the main protein in blood,
helps control the water content of tissues and blood. Plasma is
usually yellow in colour due but can become milky when it
transports fat absorbed from the intestines to other organs of the
body.
Slide 44
Year 10 Science 201244 The respiratory system The respiratory
system consists of organs that deliver oxygen to the circulatory
system for transport to all body cells. The respiratory system also
assists in removing the waste product of carbon dioxide from the
body. Oxygen is a vital element for metabolism. The exchange of
oxygen and carbon dioxide between body cells, blood and the air in
the lungs is called respiration.
Slide 45
Year 10 Science 201245 The structure of the mammalian breathing
system The human respiratory system consists of the nose, pharynx,
larynx, trachea, bronchi, and lungs (composed of bronchioles and
alveoli). The lungs are housed in an airtight pleural cavity framed
by the rib cage and diaphragm.
Slide 46
Year 10 Science 201246 Air (comprised of about 21% oxygen)
enters the nose, where tiny hairs filter out dust and particles.
Tissues moisten and warm the air, making it more suitable for gas
exchange in the lungs. Air passes from the pharynx to the larynx
(containing vocal cords) and into the trachea. The structure of the
mammalian breathing system
Slide 47
Year 10 Science 201247 The trachea divides into the left and
right bronchi which subdivide into smaller and smaller tubes called
bronchioles. These airways are lined by mucous membranes and many
cilia hairs which trap and remove particles from the lungs.
Bronchioles open into the alveoli which are clustered like grapes.
The structure of the mammalian breathing system
Slide 48
Year 10 Science 201248 The structure of the alveoli and blood
capillaries enable gaseous exchange to occur. Only one cell thick,
alveoli have direct contact with capillaries for gas exchange. The
grapelike arrangement of alveoli creates an enormous surface area
sufficient for exchanging enough oxygen and carbon dioxide for the
entire body.
Slide 49
Year 10 Science 2012 The importance of diffusion in gaseous
exchange across the alveoli. Oxygen is transported to the cells of
the body mainly by binding to haemoglobin which is found within red
blood cells. Carbon dioxide is transported by diffusion into the
plasma. Diffusion occurs because the oxygen is in higher
concentration in the alveoli and moves to the lower concentration
in the blood of the capillary. The CO2 in the blood diffuses into
the alveoli and out of the body because it also moves from high to
low concentration. Oxygen enters into alveoli from bronchioles The
oxygen molecules must diffuse through both the lining of the
alveolus and the lining of the blood capillary and is eventually
picked up by red blood cells
Slide 50
Year 10 Science 201250 Air breathed out contains more carbon
dioxide and less oxygen than air breathed in. Breathing (the
movement of air in and out of the lungs) is produced by pressure
differences created by changing the size of the pleural cavity. The
diaphragm contracts and the rib cage is raised. The volume of the
pleural cavity is increased, creating a partial vacuum between the
lung cavity and the atmosphere, and air enters the lung.
Slide 51
Year 10 Science 201251 Aerobic respiration involves
transferring energy from glucose to a cell; oxygen is needed and
carbon dioxide is produced. Cellular respiration is a process
whereby energy is released from the breakdown of molecules in food
at the cellular level. Glucose enters the cell and oxygen diffuses
in which has previously entered the body via the respiratory system
and transported to each cell through the circulatory system.
Glucose is broken apart in a series of steps to release energy
required for the body. Each reaction is assisted by enzymes. The
products of these reactions are water and carbon dioxide which
diffuses back out of the cell and eventually out of the body via
the circulation and respiratory systems.
Slide 52
Year 10 Science 201252 Anaerobic respiration can occur in human
muscles and that lactic acid is produced. Sometimes our muscles
require more oxygen than we can supply by normal breathing. Without
oxygen present, anaerobic respiration takes place. The glucose is
broken down and releases some energy. Carbon dioxide is produced
along with lactic acid. The lactic acid is a waste product and must
be removed from the body.