But infectious bacteria can make you ill. They reproduce quickly in your body. Many give off chemicals called toxins, which can damage tissue and make you sick. Examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.
Getty Images/Fuse. Head down: Jet lag symptoms include feeling sleepy during the day in your new time zone. Jet lag is what we call it when your body is reacting to these changes in your environment, which is basically your body taking time to adjust to its new place and time. Symptoms include feeling sleepy during the day in your new time zone, but also having a troubled sleep at night.
Rise and shine: Jet lag affects our body's relation to the environment. It's a condition that's related to our 'body clock' or circadian rhythm, a biological process which is part of the brain. It means we can react subconsciously to changes in our environment and know when we should sleep in the normal cycle of 24 hours.