Thursday, April 18, 2013
KUIZ ( LIFE PROCESSES )
Life Processes
Dead or Alive?
There are seven things all living organisms
do -these are called Life Processes. An
organism is only alive if it does all seven
life processes!
The Seven Life Processes –
1. M___________ - Moving parts of the body
2. R_______________ - Producing offspring
3. S_______________ - responding and reacting
4. N_____________ - Getting food to stay alive
5. E______________ - Getting rid of waste
6. R_________________ - Turning food into energy
7. G____________ - Getting to adult size
Can you think of a mnemonic to remember these processes. eg MRS NERG.
Dead or Alive?
There are seven things all living organisms
do -these are called Life Processes. An
organism is only alive if it does all seven
life processes!
The Seven Life Processes –
1. M___________ - Moving parts of the body
2. R_______________ - Producing offspring
3. S_______________ - responding and reacting
4. N_____________ - Getting food to stay alive
5. E______________ - Getting rid of waste
6. R_________________ - Turning food into energy
7. G____________ - Getting to adult size
Can you think of a mnemonic to remember these processes. eg MRS NERG.
Wednesday, April 17, 2013
HUMAN REPRODUCTION
Living Things Undergo Life Processes
D.)HUMAN REPRODUCTION
Process
Human reproduction begins with sexual intercourse, followed by nine months of pregnancy before childbirth. Many years of parental care are required before a human child becomes independent.Pregnancy
Pregnancy is the period of time during which the fetus develops, dividing via mitosis inside the female. During this time, the fetus receives all of its nutrition and oxygenated blood from the female, filtered through the placenta, which is attached to the fetus' abdomen via an umbilical cord. This drain of nutrients can be quite taxing on the female, who is required to ingest slightly higher levels of calories. In addition, certain vitamins and other nutrients are required in greater quantities than normal, often creating abnormal eating habits. Gestation period is about 266 days in humans.Birth
Once the fetus are sufficiently developed, chemical signals start the process of birth, which begins with the fetus being pushed out of the birthing canal. The newborn, which is called an Infant in humans, should typically begin respiration on its own shortly after birth. Not long after, the placenta eventually falls off on its own. The Person assisting the birth will usually detach the mother from the baby using a Cutting tool there by, cutting it off.Parental care
Human babies are nearly helpless and require high levels of parental care for many years. One important type of parental care is nursing – feeding the baby milk from the mother's mammary glands in her breasts.[2]Political and social
There are groups promoting more human reproduction and those who think reproduction ought to be limited. Natalism promotes reproduction, while anti-natalism promotes birth control as a solution to overpopulation and its effects.Reproduction
Defecation
Living Things Undergo Life
Processes
C.)Defecation
- humans need to defecate at regularly (at least twice a week)
- humans defecate to remove the indigested food materials from the body.
- faeces are solid materials which cannot be digested by the body.
- the remnants of undigested food in the body can cause diseases. If the material are not removed from the body, they can turn toxic and harm the body, causing us to fill ill.
- therefore humans need to get rid of the undigested food materials to stay healthy.
EXCRETION
Living Things Undergo Life Processes
B.)Excretion
B.)Excretion
Excretion is the removal of toxic materials, the waste products of
metabolism and substance in excess of requirements from organisms.
Metabolism is chemical reactions taking place inside cells, including
respiration.
The body excretes three main waste materials. These are Carbon
Dioxide, Urea and Water. Excretion is a very important feature to us
because without it toxic substances will build up in our bodies and kill
us. It also helps in maintaining the composition of body fluids.
The Excretory System of humans is made up of 4 structures: Two
kidneys, two ureters, a bladder, and the urethra. The kidneys act as a
filter to filter the waste products from the blood, the ureters are
tubes that transport the main waste products (urine) from the kidneys to
the bladder, where it is stored until it is excreted out of the body
through the urethra.

LIVING THINGS UNDERGO LIFE PROCESSES
Living Things Undergo Life Processes
1.Living things undergo several life processes during
their entire lifespan.
2.The life processes which living things undergo are:
- Breathing
- Excretion
- Reproduction
- Responding to stimuli
2.The life processes which living things undergo are:
- Breathing
- Excretion
- Reproduction
- Responding to stimuli
A. ) Breathing

1.Humans breathe through their lungs.
2.Inhaled air has more oxygen than exhaled air.
3.Exhaled air contains more carbon dioxide than inhaled air.
4.Exhaled air contains water vapour and a small amount of heat.
Humans need a continuous supply of oxygen for cellular
respiration, and they must get rid of excess carbon dioxide, the poisonous
waste product of this process. Gas exchange supports this cellular
respiration by constantly supplying oxygen and removing carbon dioxide.
The oxygen we need is derived from the Earth's atmosphere, which is 21%
oxygen. This oxygen in the air is exchanged in the body by the respiratory
surface. In humans, the alveoli in the lungs serve as the surface for gas
exchange.
Gas exchange in humans can be divided into five steps:
- Breathing
- External Respiration
- Gas Transport
- Internal Respiration
- Cellular Respiration
Other factors involved with respiration are:
- Adaptations of Diving Mammals
- Bohr Shift
- Control of Breathing
- Partial Pressure
- Structure of Respiratory System
Usually air will enter the
respiratory system through the nostrils. The nostrils then lead to open
spaces in the nose called the nasal passages. The nasal passages serve as
a moistener, a filter, and to warm up the air before it reaches the lungs.
The hairs existing within the nostrils prevents various foreign particles
from entering. Different air passageways and the nasal passages are
covered with a mucous membrane. Many of the cells which produce the cells
that make up the membrane contain cilia. Others secrete a type a sticky
fluid called mucus. The mucus and cilia collect dust, bacteria, and other
particles in the air. The mucus also helps in moistening the air.
Under the mucous membrane there are a large number of capillaries.
The blood within these capillaries helps to warm the air as it passes
through the nose. The nose serves three purposes. It warms,
filters, and moistens the air before it reaches the lungs. You will
obviously lose these special advantages if you breath through your mouth.
Air travels from the nasal passages to the pharynx, or more
commonly known as the throat. When the air leaves the pharynx it passes into
the larynx, or the voice box. The voice box is constructed mainly of
cartilage, which is a flexible connective tissue. The vocal chords are
two pairs of membranes that are stretched across the inside of the larynx.
As the air is expired, the vocal chords vibrate. Humans can control
the vibrations of the vocal chords, which enables us to make sounds. Food
and liquids are blocked from entering the opening of the larynx by the
epiglottis to prevent people from choking during swallowing.
The larynx goes directly into the
trachea or the windpipe. The trachea is a tube approximately 12
centimeters in length and 2.5 centimeters wide. The trachea is kept open
by rings of cartilage within its walls. Similar to the nasal passages,
the trachea is covered with a ciliated mucous membrane. Usually the cilia
move mucus and trapped foreign matter to the pharynx. After that, they
leave the air passages and are normally swallowed. The respiratory system
cannot deal with tobacco smoke very keenly. Smoking stops the cilia from
moving. Just one cigarette slows their motion for about 20 minutes.
The tobacco smoke increases the amount of mucus in the air
passages. When smokers cough, their body is attempting to dispose of the
extra mucus.
Around the center of the chest, the
trachea divides into two cartilage-ringed tubes called bronchi. Also,
this section of the respiratory system is lined with ciliated cells. The
bronchi enter the lungs and spread into a treelike fashion into smaller tubes
calle bronchial tubes.
The bronchial tubes divide and then
subdivide. By doing this their walls become thinner and have less and
less cartilage. Eventually, they become a tiny group of tubes called
bronchioles.
Each bronchiole ends in a tiny air
chamber that looks like a bunch of grapes. Each chamber contains many
cup-shaped cavities known as alveoli. The walls of the alveoli, which are
only about one cell thick, are the respiratory surface. They are thin,
moist, and are surrounded by several numbers of capillaries. The exchange
of oxygen and carbon dioxide between blood and air occurs through these walls.
The estimation is that lungs contain about 300 million alveoli. Their
total surface area would be about 70 square meters. That is 40 times the
surface area of the skin. Smoking makes it difficult for oxygen to be
taken through the alveoli. When the cigarette smoke is inhaled, about
one-third of the particles will remain within the alveoli. There are too
many particles from smoking or from other sources of air pollution which can
damage the walls in the alveoli. This causes a certain tissue to form.
This tissue reduces the working area of the respiratory surface and leads
to the disease called emphysema.
Friday, April 12, 2013
Wednesday, April 10, 2013
Subscribe to:
Comments (Atom)