OVERVIEW OF THE
HUMAN BODY
Year 10 Human Biology 2015
COURSE CONTENT
• Levels of Organisation
• Link systems to essential processes
• Internal body organisation
• Cells as the basic structure
• Link cellular structures with essential processes
FROM THE CELL TO THE BODY
• Each human develops from just one cell – the
ZYGOTE.
• That cell divides repeatedly (mitosis) and by a process
called DIFFERENTIATION the new cells become
specialised for particular functions.
• There are around 200 different types of cells in the
human body.
DIFFERENTIATION
Differentiation: stem cells (centre) can
differentiate into specialised cells
LEVELS OF ORGANISATION - CELLS
• Cells are the basic structure of all body systems
• Cells are specialised to carry out different
functions
• Cells with similar specialisations that carry out a
common function are grouped together to form
tissues
LEVELS OF ORGANISATION – TISSUES, ORGANS
AND SYSTEMS
• Tissues are the second structural level
• Different types of tissue work together as organs
• An organ is normally made up of two or more tissues
• A group of organs that work together is called a system
• All body systems are integrated to form the organism
LEVELS OF ORGANISATION
STRUCTURAL ORGANISATION OF THE BODY
• Organism
• System
eg/ Digestive
• Organ
eg/ Small Intestines
• Tissue
eg/ Bones
• Cell
eg/ Muscle cell
• Organelle
eg/ Mitochondria
• Molecule
eg/ Water (H2O)
• Atom
eg/ Carbon
BODY SYSTEMS
How many body systems can you name?
INTERNAL BODY ORGANISATION: BODY
SYSTEMS
• Digestive system
• Muscular system
• Respiratory system
• Skeletal system
• Integumentary system
• Lymphatic system
• Circulatory system
• Endocrine system
• Urinary system
• Reproductive system
(male and female)
• Nervous system
RESPIRATORY SYSTEM
• Consists of:
• Mouth, trachea, bronchi,
bronchioles, lungs
(alveoli)
• Function:
• Gaseous exchange
between the external
environment and the
blood
NERVOUS SYSTEM
• Consists of:
• Brain, spinal cord,
nerves/nerve cells
• Function:
• Regulation of all body
activities
• Learning and memory
• Responsiveness
CIRCULATORY SYSTEM
• Consists of:
• Heart, arteries, veins,
capillaries
• Functions:
• Transport of life-sustaining
materials to the body’s cells
• Removal of metabolic wastes
from cells
• Temperature Regulation
DIGESTIVE SYSTEM
• Consists of:
• Mouth, oesophagus,
stomach, SI, LI, liver
• Functions:
• Breakdown and
absorption of food
materials
• Excretion of solid waste
from the body
INTEGUMENTARY SYSTEM
• Consists of:
• Skin, hairs, nails
• Functions:
• External support of the body
• Protection of the body
• Excretes unwanted
substances
• Body temperature regulation
SKELETAL SYSTEM
• Consists of:
• Axial bones, appendicular bones,
joints
• Functions:
• Internal support
• Attachment for muscles to allow
movement
• Production of blood cells
• Joints allow a flexible framework
MUSCULAR SYSTEM
• Consists of:
• Cardiac muscle, skeletal
muscle, smooth muscle
• Functions:
• Body movement
• Production of body heat
URINARY SYSTEM
• Consists of:
• Kidneys, ureter, urethra,
bladder
• Functions:
• Filtration of blood to allow
excretion of waste products
• Maintenance of fluid volume
• Maintenance of the chemical
composition of blood
REPRODUCTIVE SYSTEM
• Consists of:
• Testes, vas deferens,
urethra, ovaries, fallopian
tubes, uterus, vagina
• Functions:
• Production of sex cells
• Transfer of sex cells
• Provide an environment for
the growth and development
of the embryo until birth
ENDOCRINE SYSTEM
• Consists of:
• Glands such as adrenal,
thyroid, pancreas etc
• Functions:
• Secretion of hormones
for chemical regulation
of the body
LYMPHATIC SYSTEM
• Consists of:
• Lymph nodes, lymph
vessels
• Functions:
• Body immunity
• Absorption of fats
• Drainage of tissue fluid
BODY SYSTEMS AND ESSENTIAL PROCESSES
Metabolism
All systems
Ingestion
Digestive
Movement
Muscular; Skeletal; Nervous
Responsiveness
Nervous; Endocrine
Growth
All systems
Excretion
Urinary; Skin; Respiratory;
Digestive
Differentiation
All systems
Reproduction
Reproductive
WORK TO BE COMPLETED
• Complete Body systems sheet
• Link the Body systems to the Essential
processes
• Answer the Section one review questions.
CELLS
Year 10
Human Biology 2015
CELLS
• Different cells are specialised for different tasks
• Shape and structure of a cell varies according to
the task they perform
• Certain structures are common to most cells
ANIMAL CELLS VS PLANT CELLS
CELL STRUCTURES
• Cell membrane
• Cytoplasm
• Organelles
• Nucleus
• Mitochondria
• Centrioles
• Golgi Apparatus
• Lysosomes
• Endoplasmic Reticulum
• Cytoskeleton –
microfilaments,
microtubules
• Inclusions
• Cillia / Flagella
CELL MEMBRANE
• Surrounds and forms the outer boundary of the
cell
• Very thin
• Allows certain substances to enter and leave the
cell
CELL MEMBRANE
CYTOPLASM
• Thick fluid between the cell membrane and the
nucleus of the cell
• 75% to 90% water
• All the cell’s contents are suspended in the
cytoplasm
NUCLEUS
• All the structures
within the cell are
called organelles
• Nucleus – largest
organelle in cells
• The “brain” of the
cell
Electron micrograph of cell
nucleus, showing the double
membrane and nuclear pores
ORGANELLES
Electron micrograph showing
endoplasmic reticulum with
ribosomes attached
Endoplasmic reticulum
Rough – protein
synthesis and
packaging
Ribosomes attach to
this structure.
Smooth – Lipid/steroid
synthesis and storage
Ribosomes
Site of protein
synthesis
Mitochondria
Associated with energy
release in the cell
ORGANELLES
Figure 3.8 Cells from the lining
of the trachea showing cilia
Figure 3.9 Scanning electron
micrograph showing sperm cells
with flagella
ORGANELLES
• Centrioles
• Involved in the reproduction of the cell
• Golgi apparatus
• Package proteins for release from the cell
• Others
• Lysosomes
• Cilia and Flagella
OTHER CELL ORGANELLES…
• Lysosomes
• Contain acid enzymes that break down waste materials and cellular debris.
They can be described as the stomach of the cell.
• Digest excess or worn-out organelles, food particles, and engulfed viruses or
bacteria.
• Cytoplasmic Inclusions
• Non-living cellular components. Eg Lipids, Glycogen, Pigments,
PUTTING IT ALL TOGETHER!
CELLULAR STRUCTURES AND ESSENTIAL
PROCESSES
Metabolism
Cytoplasm; Mitochondria
Ingestion
Lysosomes; Golgi app.
Movement
Responsiveness
Cytoskeleton; Cilia and
Flagella
Nucleus
Growth
Ribosomes; Nucleus
Excretion
Differentiation
Cell membrane; Golgi
apparatus
Inclusions; Ribosomes
Reproduction
Centrioles; Nucleus
WORK TO BE COMPLETED
• Cell structures worksheet
• Summary tables of essential processes