Respiration & Circulation
What structure in the lungs has tiny air sacs surrounded by capillaries where oxygen enters the blood?
Alveoli?
Where does most digestion and absorption of food molecules into the bloodstream happen?
The small intestine (especially the villi)
What process do cells use to make usable energy from oxygen and glucose? Write the name.
Aerobic cellular respiration?
Name the receptors used in touch and hearing.
Mechanoreceptors
What two systems work together to deliver oxygen to cells?
Respiratory and circulatory systems
Name the body system that carries oxygen and glucose to cells.
The Circulatory system (or cardiovascular system)?
What small molecule from food is carried by the circulatory system to cells for energy?
glucose (or food molecules)
What are the waste products of aerobic cellular respiration that blood carries away?
Carbon dioxide and water?
What are the electrical signals that travel along neurons called?
Neural messages or electrical impulses
When food molecules enter the bloodstream, which system moves them to cells?
Circulatory system (after absorption by digestive system)
Explain briefly how oxygen gets from the air into body cells. (Answer in 2–3 sentences.)
Air enters lungs → oxygen moves into alveoli → oxygen diffuses into capillaries → blood carries oxygen to cells
Describe how food is transformed and moved from the mouth to the bloodstream in 3 steps.
Mouth (chewing + saliva) → stomach (breakdown) → small intestine (digestion + absorption into bloodstream)
Why do cells die if they do not get oxygen or glucose?
Without oxygen or glucose, cells cannot produce energy and therefore cannot maintain life processes.
What name is given to the chemicals that move across synapses to pass a message to the next neuron?
Neurotransmitters
A patient has trouble breathing, fatigue and a hard time thinking clearly. What organ systems would be affected?
All systems
If the respiratory system fails and oxygen cannot enter the body, what happens to most other organ systems and why?
Many systems will fail or be affected because cells cannot get oxygen, so they die and organs stop working.
Explain why the circulatory and digestive systems must work together for cells to get nutrients.
The digestive system breaks food into molecules; the circulatory system transports those molecules to cells
Describe the role of the excretory system in dealing with waste from cellular respiration and how it connects to circulation.
Blood carries wastes (CO2, water) to organs like lungs and kidneys; excretory system removes these wastes from the body
What path would a neural message take from one neuron to another?
Dendrite — receives incoming signals → Cell Body — signal passes through → Axon — carries impulse away from the cell body; Synapse — gap between neurons; Neurotransmitters — chemicals crossing the synapse
Why would a symptom of a decreased production of red blood cells be severe headaches?
Red blood cells carry oxygen, if the brain is not receiving enough oxygen or other resources headaches can occur
Describe the path a red blood cell takes from the alveoli to a body cell, naming the major structures/systems involved.
Air → alveoli → capillary → pulmonary vein → left side of heart → pumped via arteries → capillaries near cells → oxygen diffuses into cells
Predict what might happen to cells if the small intestine could not absorb nutrients. Include one short-term and one long-term effect.
Short-term: cells may be energy-deprived and not function properly; Long-term: malnutrition, organ damage, growth problems
Give an example of how a problem in the circulatory system could reduce cellular respiration.
Example: If blood flow is reduced, less oxygen/glucose reach cells so cellular respiration slows and cells may die
Explain how a sensory neuron and a motor neuron work together when you touch something hot. (2–3 sentences.)
Sensory neuron senses heat and sends a message to the spinal cord then to the brain; the brain receives and processes the message; then sends a message to the motor neuron which sends a message to muscles to pull the hand away
Create a short scenario (2–3 sentences) that shows how a problem in the nervous system could lead to issues in digestion and circulation. Then identify the chain of effects.
Example scenario: Damage to nerves that control stomach muscles slows digestion → food builds up and nutrients are not absorbed → circulatory system receives fewer nutrients to deliver to cells. Chain: Nervous → Digestive → Circulatory.