TRANSPORT

Phloem is responsible for the transport of organic materials such as sugars produced by photosynthesis.

The evaporation of water from the leaves, known as transpiration, creates a negative pressure that pulls water up through the xylem.

A mature leaf is typically a source of sucrose, not a sink, as it produces sugars through photosynthesis.

Human plasma proteins include fibrinogen and albumin, but not hemoglobin, which is found in red blood cells.

Platelets are the blood components involved in clotting.

Oxygenated blood from the lungs enters the left atrium of the heart.

Root hairs increase the surface area for water and nutrient absorption from the soil.

An open circulatory system is where blood flows freely through body cavities and directly contacts tissues.

The cortex is the part of the root located between the epidermis and the endodermis.

Osmosis is the movement of water molecules from a region of higher water potential to a region of lower water potential through a semi-permeable membrane.

Transpiration is the process of water loss from the aerial parts of plants in the form of vapor.

Guard cells regulate the opening and closing of stomata by changing their turgor pressure.

Leukemia affects the blood, bone marrow, and lymphatic system, leading to abnormal production of blood cells.

The rhythmic pumping of blood by the heart is commonly referred to as the heartbeat.

Diastole is the phase of the cardiac cycle when the heart muscle relaxes and allows the chambers to fill with blood.

The lumen is the central cavity of xylem vessels through which water and minerals are transported.

White blood cells (WBCs) are colorless, nucleated, and larger than red blood cells (RBCs).

Thalassemia is an inherited blood disorder that affects the production of hemoglobin.

The ascent of sap refers to the upward movement of water and minerals from roots to other parts of the plant.

Transpiration primarily occurs through stomata, which are small openings on the surface of leaves.

Atmospheric pressure does not significantly affect the rate of transpiration compared to humidity, wind speed, and temperature.

Phloem is the vascular tissue responsible for transporting synthesized food, primarily sucrose, throughout the plant.

In an open circulatory system, blood flows freely through body cavities and directly bathes tissues.

Unicellular organisms do not require a specialized transport system as they can rely on diffusion for the movement of substances.

Earthworms have a closed circulatory system where blood is contained within vessels.

Red Blood Cells (RBCs) contain hemoglobin, which binds oxygen and transports it throughout the body.

The pulmonary circuit involves the flow of blood between the heart and the lungs for oxygenation.

During systole, the heart muscle contracts, pumping blood into the circulation.

Platelet dysfunction can lead to issues with blood clotting, as platelets are crucial for the clotting process.

Myocardial infarction, commonly known as a heart attack, is caused by a blockage in the coronary arteries, leading to reduced blood flow to the heart muscle.

Atherosclerosis is characterized by the narrowing of arteries due to the buildup of plaque, which can restrict blood flow.

Roots absorb water and minerals through both active and passive transport mechanisms.

The human heart has four chambers: two atria and two ventricles.

ATP provides the energy required for the active transport of minerals across root cell membranes.

The root cap protects the delicate root tip as it grows through the soil.

Root hairs absorb minerals via diffusion when the concentration of minerals in the soil is higher than in the root cells.

The cell membrane acts as a selective barrier that prevents the leakage of cell sap from root hairs.

Transpiration is the process where water is lost in the form of vapor from the aerial parts of plants, primarily through stomata.

Stomata are primarily involved in transpiration, the process of water vapor loss from the plant.

Desert plants often develop spines or smaller leaves to reduce the surface area and thus reduce water loss through transpiration.

Stomata open when guard cells become turgid due to the uptake of water, which increases their turgor pressure.

Transpiration pull aids in the ascent of sap in the xylem by creating a negative pressure that helps pull water upward from the roots.

Transpiration is sometimes considered an "evil" because excessive water loss can lead to dehydration and potentially the death of the plant.

High atmospheric humidity decreases the transpiration rate because it reduces the gradient for water vapor diffusion from the leaf to the atmosphere.

Wind reduces the vapor concentration around leaves, thereby increasing the rate of transpiration.

Guard cells contain chloroplasts, which allow them to perform photosynthesis and regulate stomatal opening.

The primary function of xylem is the transport of water and dissolved minerals from roots to other parts of the plant.

Lignin strengthens the walls of xylem vessels, providing structural support and enabling water transport under tension.

Sieve tubes in phloem lack a nucleus and vacuole, which allows for efficient transport of nutrients.

The movement of organic food through phloem is termed translocation, which involves the transport of sugars and other metabolic products.

According to the Munch hypothesis, translocation occurs due to a turgor pressure gradient between the source (where sugars are loaded) and the sink (where sugars are used or stored).

Sieve plates in phloem allow cytoplasmic continuity between sieve tube cells, facilitating the flow of nutrients.

In the context of translocation, "source" refers to leaves synthesizing sucrose, which is then transported to other parts of the plant.

Companion cells in phloem load sugars into sieve tubes via active transport, aiding in the efficient translocation of nutrients.

An open circulatory system allows blood to directly contact tissues via sinuses, which is characteristic of many invertebrates.

An open circulatory system is found in arthropods and molluscs, where blood flows freely within body cavities and directly bathes tissues.

A defining feature of a closed circulatory system is that blood remains confined to vessels and never contacts tissues directly, which is typical in vertebrates.

The circulatory system transports a variety of substances including gases (like oxygen and carbon dioxide), nutrients, hormones, defense proteins, and waste products.

Unicellular organisms exchange gases like O₂ and CO₂ through direct diffusion across their cell membrane.

In open circulatory systems, "sinuses" refer to open spaces where blood bathes tissues directly.

Plasma makes up about 55% of blood by volume and is the liquid component of blood that carries cells and proteins throughout the body.

The primary function of hemoglobin in red blood cells (RBCs) is to transport oxygen from the lungs to body tissues and carry carbon dioxide back to the lungs.

Lymphocytes, a type of white blood cell (WBC), are responsible for producing antibodies as part of the immune response.

Platelets are essential for blood clotting, helping to prevent excessive bleeding by forming clots at sites of injury.

Leukemia is characterized by an abnormal increase in white blood cells (WBCs) and often a decrease in red blood cells (RBCs), leading to various complications.

Thalassemia major is an inherited blood disorder that occurs due to mutations inherited from both parents, affecting the production of hemoglobin.

The pericardial cavity contains pericardial fluid, which helps reduce friction during heart movements.

The left ventricle has thicker walls because it pumps oxygenated blood to the entire body, requiring more force compared to the right ventricle.

The bicuspid (or mitral) valve separates the left atrium and left ventricle, preventing backflow of blood when the ventricle contracts.

Pulmonary circulation specifically transports blood between the heart and the lungs for oxygenation.

Systole refers to the contraction of heart chambers, which pumps blood into circulation.

Tachycardia is defined as a heart rate exceeding 100 beats per minute (bpm) in adults, which can be a response to various physiological or pathological conditions.

Pulse rate directly measures the heart rate, reflecting the number of heartbeats per minute.

Capillaries have the thinnest walls, which facilitates the exchange of gases, nutrients, and waste products between blood and tissues.

The hepatic artery supplies oxygenated blood to the liver, which is essential for its metabolic functions.

The superior vena cava carries deoxygenated blood from the upper body to the right atrium of the heart.

Ibn-al-Nafees first explained pulmonary circulation, describing how blood flows from the heart to the lungs and back.

Atherosclerosis involves the deposition of LDL (low-density lipoprotein) and cholesterol in the arterial walls, leading to plaque formation.

Arteriosclerosis causes arteries to lose elasticity, making them stiff and less capable of dilating and contracting properly.

Smoking is a modifiable risk factor for myocardial infarction, as it can be changed or controlled to reduce the risk of heart disease.

The pulmonary vein carries oxygenated blood from the lungs to the heart, specifically to the left atrium.

Neutrophils primarily function by phagocytosis, engulfing and digesting pathogens and cellular debris.

Red blood cells (RBCs) are primarily destroyed in the spleen and liver, where they are broken down and recycled.

Fibrinogen is the plasma protein involved in clotting, converting to fibrin during the clotting process to help form a blood clot.

The systemic circuit starts from the left ventricle, which pumps oxygenated blood into the aorta and throughout the body.

Coronary arteries supply blood to the walls of the heart, providing the necessary nutrients and oxygen to cardiac muscle tissue.

Basophils, a type of white blood cell, release heparin, which is an anticoagulant that helps prevent blood clotting.

A normal resting heart rate for adults ranges between 60 to 100 beats per minute (bpm).

Capillaries are adapted for the exchange of substances due to their thin, permeable walls, which allow for the efficient transfer of gases, nutrients, and waste products.