Cell City 🔬
What is the basic unit of life?
A Cell
Which organ system brings oxygen into the body?
The respiratory system.
What molecule provides immediately usable energy for many cell activities?
ATP (adenosine triphosphate).
What gas do humans breathe in that is needed for aerobic respiration?
Oxygen
What is glucose?
A simple sugar that cells can use as a fuel source.
What type of cell makes up muscle tissue?
A muscle cell, also called a muscle fiber in skeletal muscle.
What organelle contains DNA and helps direct cell activities?
The nucleus
Which organ system transports oxygen and glucose through the blood?
The circulatory system.
What sugar do cells break down during cellular respiration to help release energy?
Glucose.
In which organs does oxygen enter the blood from the air?
The lungs, specifically across the alveoli.
Which organ produces insulin and glucagon?
the pancreas
What is muscle fatigue?
reduced ability to maintain or produce force during activity.
Put these in order, from smallest to largest: organ, organism, cell, tissue, organ system.
Cell → tissue → organ → organ system → organism.
Which two systems work together to deliver oxygen from the lungs to muscle cells?
The respiratory and circulatory systems.
What is the main purpose of cellular respiration?
to transfer energy from glucose into ATP that cells can use.
Complete the pathway: lungs → ______ → muscle cells.
Blood, carried through the circulatory system.
After a meal, blood glucose rises. Which hormone helps lower it?
Insulin. It helps body cells take up glucose and promotes storage of glucose as glycogen.
Why do muscle cells need ATP?
ATP provides energy for processes involved in muscle contraction and relaxation.
A muscle cell contains many mitochondria. How does this structure help the cell do its job?
Mitochondria help release usable energy through cellular respiration, supporting the muscle cell's high energy demand.
A runner's breathing and heart rate increase during exercise. Explain why.
Working muscles need more oxygen and glucose to support ATP production, and carbon dioxide must be carried away. Breathing and circulation increase to help meet these needs.
Compare aerobic and anaerobic energy pathways in terms of oxygen.
Aerobic respiration requires oxygen. Anaerobic pathways can produce ATP without oxygen; in human muscle cells, this includes lactic acid germentation
Where does carbon dioxide produced by cellular respiration go so it can leave the body?
It enters the blood, is transported to the lungs, moves into the alveoli and is exhaled.
Blood glucose drops between meals. Which hormone helps raise it, partly by signaling the liver to release glucose?
glucagon
How can the body store glucose for later use?
By converting it to glycogen, stored mainly in the liver and skeletal muscles.
A cell's membrane stops functioning properly. Explain one way this could affect the whole organism.
The cell may not regulate substances entering and leaving. This can disrupt cell function, tissues, organs and eventually the organis
A person has a problem that prevents oxygen from reaching their muscles efficiently. Predict one effect on muscle activity and explain wh?
Muscles may have difficulty sustaining activity because aerobic cellular respiration is limited, reducing their ability to produce ATP efficiently
A student says, 'My muscles use glucose directly as their only source of usable energy.' Correct the statement.
Glucose contains chemical energy, but cells transfer energy from glucose into ATP. ATP powers muscle contraction and other cellular activity
A diagram shows oxygen entering the lungs but not reaching the muscles. Which body system is most directly responsible for transporting the oxygen from the lungs to the muscles? Explain.
The circulatory system transports oxygen in the blood from the lungs to body tissues.
Explain how insulin and glucagon help maintain homeostasis when blood glucose changes.
When glucose is high, insulin helps lower it. When glucose is low, glucagon helps raise it. These opposing responses help keep blood glucose within a suitable range through negative feedback
A track start continues exercising for a long time. Explain how the digestive, circulatory, respiratory and muscular systems work together to support this activity.
Digestion supplies nutrients; the respiratory system brings in oxygen; the circulatory system delivers oxygen and nutrients to muscles and carries away carbon dioxide; muscle cells use ATP to contract. Stored fuels also help supply energy over time.