Download answerKey

Human Body
A) Summarize the hierarchical organization of multi-cellular organisms.
Cells work together to form tissues – tissues work together to form organs – organs work together to form organ
systems – organ systems work together to make an organism
B) There are many body systems which carry out important functions.
 Summarize the functions of the digestive system.
The digestive system has three main functions in the human body. It breaks down food into molecules
the body can use. These molecules are absorbed into the blood and carried throughout the body. The
digestive system will also eliminate solid waste from the body.
 Summarize the functions of the respiratory system.
The respiratory system has three main jobs in the human body. It will bring air into the body and
transport it to the lungs. In the alveoli, gas exchange will occur and the oxygen from the air will move
into the blood stream. The waste products will move from the blood stream and into the alveoli. When
you exhale, these waste products are removed from the body
 Summarize the functions of the reproductive system.
The function of the reproductive system is to ensure survival of the species. It produces sex cells (egg or
sperm) and it will transport the cells when necessary. The female reproductive system also nurtures the
developing offspring. Both male and female reproductive systems produce hormones that help to
maintain homeostasis.
 Summarize the functions of the circulatory system.
The circulatory system is the transportation system of the body. It carries needed substances to cells
and carries waste products away from cells. In addition, blood contains cells that fight disease.
 Summarize the functions of the excretory system.
The excretory system removes excess water, urea, carbon dioxide, and other wastes from our blood.
C) There are many organs or parts of the body associated with specific body systems.
 Construct an organ or part of the body that is associated with the
digestive, respiratory, reproductive, circulatory and excretory systems.
 Explain how each organ works within the
system it is associated with.
a) Digestive – The stomach is a J-shaped pouch that
is used to chemically and mechanically break
down food into their nutrients.
b) Respiratory – The lungs are where the alveoli are
located and the place where gas exchanged happens.
They give oxygen to the blood and take away the
waste products from the blood.
c) Reproductive – The uterus is the part of
the female reproductive system where
the fetus is nurtured until birth.
d) Circulatory – The heart is the pump of the circulatory
system and helps to circulate and deliver needed
nutrients throughout the body.
e) Excretory – The kidneys filter blood and removed
waste products. These waste products are then
removed from the body.
D) Explain the process of homeostasis.
Homeostasis is the process of the body keeping a constant internal environment despite changes in the outside
environment.
E) Identify two ways homeostasis is maintained within the body.
1. The body will adjust to keep the temperature constant by shivering when you are too cold and sweating
when you are too hot.
2. The heart rate and breathing rate speed up and slows down depending on the oxygen needs of the body
F) Explain how the above 5 body systems work together to help the body function properly.
The respiratory system helps to bring oxygen into the body. It works very closely with the circulatory system to
carry the oxygen throughout the body to all the cells. It will also transport waste products to the respiratory
system for gas exchange where the lungs exhale the waste out of the body. The circulatory system also carries
nutrients to the cells in the body after they have been digested and absorbed in the digestive system. The
excretory system works with the circulatory system to help filter out waste products from the blood. The kidney
does this and then it is removed from the body as liquid waste. The reproductive system produces hormones
that are carried throughout the body by the blood. These hormones help to regulate growth and development
as well as maintain homeostasis.
G) Explain how environmental issues can affect the human body.
1. Air pollution can make it hard for a person to breathe while they are outdoors. This type of pollution can
also lead to the development of asthma in some humans.
2. Excessive heat can lead to dehydration of the body if you do not consume enough water to replace what has
been lost due to sweating.
3. Water pollution is when water becomes contaminated due to toxins being dumped into the ground or
nearby water systems. These toxins can cause a person to become ill if they ingest the water or break out in
a rash, if the water comes in contact with their skin.
H) Describe three ways you can help keep your body healthy.
1. Exercise regularly – at least 30 minutes a day
2. Eat a healthy balanced diet
3. Get the recommended amount of sleep for a person your age