💦 • Lesson 1.4 : Transport in Plants & Animals (Bio) Flashcards
After this lesson, you will have mastered all about the xylem and phloem, water uptake, and transpiration in plants, as well as translocation, circulatory systems, the heart, blood and vessels in animals.
What is the function of the xylem in plants?
Xylem — Transports water and mineral ions, and supports the plant.
What is the function of the phloem in plants?
Phloem — Transports sucrose and amino acids.
What are the functions of root hair cells?
They absorb water by osmosis,
Take in minerals by active transport,
And increase surface area for efficient absorption.
Why do root hairs have a large surface area?
A large surface area helps absorb more water and mineral ions efficiently.
What pathway does water take through a plant?
Root hair cells → Root cortex cells → Xylem → Mesophyll cells (in the leaf).
Describe Transpiration in plants
Transpiration is the loss of water vapor from leaves.
Where does water evaporate during transpiration in plants?
Water evaporates from the surfaces of the mesophyll cells into the air spaces, and then diffuses out of the leaves through the stomata as water vapor.
How do temperature and wind affect transpiration?
Higher temperature → More evaporation, faster transpiration.
More wind → Removes moisture, faster transpiration.
How does humidity affect transpiration?
Higher humidity → Slower transpiration (air already full of water vapor).
Why do plants wilt (wither)?
More water lost than absorbed → Cells lose water, become flaccid, plant droops.
Wilting reduces surface area → Slows water loss, prevents more dehydration.
What is translocation in plants?
Translocation is the movement of sucrose and amino acids in the phloem from sources to sinks.
What are sources in a plant?
Parts that release sucrose or amino acids (ex., leaves during photosynthesis).
What are sinks in a plant?
Parts that use or store sucrose or amino acids (ex. roots, fruits, growing shoots).
What is the circulatory system in animals?
The circulatory system is a system of blood vessels with a pump and valves to ensure one-way flow of blood.
How is blood pumped around the body?
Blood is pumped away from the heart in arteries and returns to the heart in veins.
How can the heart be monitored?
With an electrocardiogram, by pulse rate, and listening to sounds of valves closing.
What is coronary heart disease?
Blockage of coronary arteries — this reduces blood flow to the heart.
What are the risk factors for coronary heart disease?
Diet, lack of exercise, stress, smoking, genetics, age, sex (men at higher risk).
How do diet and exercise reduce the risk of coronary heart disease?
Healthy diet (low in fat, high in fiber) reduces plaque build-up.
Regular exercise strengthens the heart, improves circulation, and reduces stress.
How does the heart function?
1 — Atria contracts → Pushes blood into ventricles.
2 — Ventricles contract → Push blood to lungs (right side) and body (left side).
3 — Valves prevent blood from flowing backward.
How does physical activity affect heart rate?
Exercise increases heart rate to supply more oxygen to muscles.
Regular activity can lower resting heart rate over time.
What is the structure of arteries?
Arteries — Thick walls, small lumen, no valves.
What is the structure of veins?
Veins — Thin walls, large lumen, valves to prevent backflow.
What is the structure of capillaries?
Capillaries — Very thin walls, tiny lumen, no valves.
How is the structure of arteries related to blood pressure?
Arteries have thick walls to handle high pressure from the heart.
What are the functions of capillaries?
Gas exchange (oxygen and carbon dioxide).
Nutrient and waste exchange between blood and tissues.
What is the function of the vena cava?
The Vena Cava carries deoxygenated blood from the body to the heart.
What is the function of the aorta?
The Aorta carries oxygenated blood from the heart to the body.
What is the function of the pulmonary artery?
The pulmonary artery carries deoxygenated blood from the heart to the lungs.
What is the function of the pulmonary vein?
The pulmonary vein carries oxygenated blood from the lungs to the heart.
What are the components of blood?
Red blood cells, white blood cells, platelets and plasma.
What is the role of the haemoglobin in red blood cells?
Haemoglobin binds to oxygen in the lungs, carries it through the blood, and releases it in tissues for respiration.
What is the role of white blood cells in phagocytosis?
Phagocytosis: White blood cells engulf and digest pathogens to protect the body from infection.
What is the role of white blood cells in antibody production?
White blood cells produce antibodies to recognize and destroy specific pathogens.
What is the role of platelets in clotting?
Platelets help form blood clots to prevent excessive bleeding after injury, and the entry of pathogens.
What is the role of plasma in blood?
Plasma transports blood cells, ions, nutrients, urea, hormones, and carbon dioxide throughout the body.
What is the function of lymphocytes?
Lymphocytes produce antibodies and destroy infected cells to help protect the body against infections.
