Cellular Ion Transport Quiz

Podcast Beta

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the name of the single cell from which the human body develops?

Cytoplasm

Zygote (correct)

Ovum

Spermatozoon

What is the watery fluid enclosing the organelles in a cell called?

Cytosol (correct)

Nucleus

Cholesterol

Plasma membrane

What is the function of the plasma membrane in a cell?

Produces cytosol

Regulates intracellular environment (correct)

Encloses the nucleus

Stores genetic make-up

What are the two components of phospholipid molecules in the plasma membrane?

Hydrophilic head and hydrophobic tail Signup and view all the answers

Which component of the plasma membrane creates a water-repelling central layer?

Hydrophilic tails Signup and view all the answers

What is the function of membrane proteins in the plasma membrane?

Provide channels for the passage of electrolytes and non-lipid soluble substances Signup and view all the answers

What is the main function of the plasma membrane?

Control the entry and exit of substances Signup and view all the answers

What type of transport occurs when substances move down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

What is facilitated diffusion?

A passive process using specialized protein carrier molecules to transport substances across the membrane Signup and view all the answers

How is active transport defined?

The movement of substances up their concentration gradient using chemical energy in the form of ATP Signup and view all the answers

What is the sodium-potassium pump responsible for?

Maintains the unequal concentrations of sodium and potassium ions and uses up to 30% of cellular ATP Signup and view all the answers

Which type of protein provides mechanical support and guidance tracking for internal movement within the cell?

Microtubules Signup and view all the answers

What is the main function of microvilli in the small intestine?

Maximizing absorption of nutrients Signup and view all the answers

Which structure contains a pair of centrioles and plays an important role in cell division?

Centrosome Signup and view all the answers

During which phase of the cell cycle do chromosomes replicate?

Synthesis of DNA (S phase) Signup and view all the answers

What is the process known as when ageing cells are programmed to 'self-destruct'?

Apoptosis Signup and view all the answers

What is the period between two cell divisions known as?

Cell cycle Signup and view all the answers

What is the main function of cilia along the free borders of some cells?

Propelling substances along the surface Signup and view all the answers

Which type of cells line the small intestine and have microvilli for absorption?

Absorptive cells Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Cells in 'Go' phase are usually highly active despite being called resting. Signup and view all the answers

What is the main function of microfilaments in a cell?

Anchoring to the inside of the cell membrane Signup and view all the answers

Which ion is the principal intracellular cation?

Potassium Signup and view all the answers

What process is responsible for maintaining ion transport by pumping excess Na+ out of the cell in exchange for K+?

Active transport Signup and view all the answers

Which process involves the cell membrane engulfing fluid and particles, forming a vacuum that later becomes a membrane-bound vacuole?

Pinocytosis Signup and view all the answers

What does the nucleus contain?

Genetic material in the form of DNA Signup and view all the answers

Which organelle generates ATP for energy production?

Mitochondria Signup and view all the answers

What is the function of lysosomes?

Contain enzymes involved in breaking down organelles and large molecules inside the cell Signup and view all the answers

What does the cytoskeleton provide within the cell?

An internal support system and guides the movement of materials around the cell interior Signup and view all the answers

What is the function of endoplasmic reticulum?

Synthesize proteins, lipids, and steroid hormones Signup and view all the answers

What is the structure responsible for packaging and transporting proteins to the cell membrane for export?

Golgi apparatus Signup and view all the answers

What are ribosomes composed of?

RNA and protein Signup and view all the answers

Which ion is the principal extracellular cation?

Sodium Signup and view all the answers

What process involves the cell membrane engulfing larger particles, such as cell fragments, foreign materials, or microbes?

Phagocytosis Signup and view all the answers

What is the function of the plasma membrane in a cell?

Regulating the intracellular environment Signup and view all the answers

What is the watery fluid enclosing the organelles in a cell called?

Cytosol Signup and view all the answers

What structure contains a pair of centrioles and plays an important role in cell division?

Centrosome Signup and view all the answers

What is the main function of microfilaments in a cell?

Providing mechanical support and guidance for internal movement within the cell Signup and view all the answers

Which organelle is involved in aerobic respiration and ATP synthesis?

Mitochondria Signup and view all the answers

What process involves the cell membrane engulfing larger particles like cell fragments or foreign materials?

Phagocytosis Signup and view all the answers

Which component of the plasma membrane creates a water-repelling central layer?

Phospholipids Signup and view all the answers

During which phase of the cell cycle do chromosomes replicate?

S phase Signup and view all the answers

What is the main function of cilia along the free borders of some cells?

Movement of materials Signup and view all the answers

Which ion is the principal intracellular cation?

Potassium (K+) Signup and view all the answers

What does the nucleus contain?

Genetic material (DNA) Signup and view all the answers

What is the function of the plasma membrane in a cell?

Cellular communication Signup and view all the answers

What is the main function of the centrosome within a cell?

Directing organization of microtubules within the cell Signup and view all the answers

Which structure contains microtubules and allows movement from the plasma membrane in some types of cells?

Microvilli Signup and view all the answers

What is the primary function of cilia along the free borders of some cells?

Moving substances along the surface Signup and view all the answers

What is the period between two cell divisions known as?

Cell cycle Signup and view all the answers

What is the main function of microfilaments within a cell?

Providing mechanical support and shape to the cell Signup and view all the answers

What process results in two new genetically identical daughter cells?

Mitosis Signup and view all the answers

Which component directs the organization of microtubules within a cell?

Centrosome Signup and view all the answers

Which phase involves further growth and preparation for cell division?

Second gap phase (G2) Signup and view all the answers

What type of cells line the small intestine and have microvilli for absorption?

Absorptive cells Signup and view all the answers

What is responsible for packaging and transporting proteins to the cell membrane for export?

Golgi apparatus Signup and view all the answers

What process involves ageing cells being programmed to 'self-destruct'?

Apoptosis Signup and view all the answers

Which component of the plasma membrane creates a water-repelling central layer?

Hydrophobic tails Signup and view all the answers

What type of transport occurs when substances move down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

What is the main function of microvilli in the small intestine?

Absorption of nutrients Signup and view all the answers

What process involves the cell membrane engulfing fluid and particles, forming a vacuum that later becomes a membrane-bound vacuole?

Pinocytosis Signup and view all the answers

What organelle generates ATP for energy production?

Mitochondrion Signup and view all the answers

Which ion is the principal intracellular cation?

Potassium (K+) Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Resting and not preparing for division Signup and view all the answers

What does the sodium-potassium pump maintain unequal concentrations of on either side of the plasma membrane?

Sodium and potassium ions Signup and view all the answers

What is the process known as when ageing cells are programmed to 'self-destruct'?

Apoptosis Signup and view all the answers

What is the structure responsible for packaging and transporting proteins to the cell membrane for export?

Golgi apparatus Signup and view all the answers

What are ribosomes composed of?

Nucleic acids and proteins Signup and view all the answers

What does the cytoskeleton provide within the cell?

Mechanical support and movement Signup and view all the answers

What is the primary function of the plasma membrane in a cell?

To regulate the passage of substances into and out of the cell Signup and view all the answers

Which component forms the structure of the plasma membrane?

Cholesterol Signup and view all the answers

What is the watery fluid containing organelles in a cell called?

Cytoplasm Signup and view all the answers

What is the main function of the centrosome within a cell?

To facilitate movement of chromosomes during cell division Signup and view all the answers

Which structure is responsible for packaging and transporting proteins to the cell membrane for export?

Endoplasmic reticulum Signup and view all the answers

What is the primary function of cilia along the free borders of some cells?

Movement of substances along the cell surface Signup and view all the answers

What process involves the cell membrane engulfing larger particles, such as cell fragments, foreign materials, or microbes?

Phagocytosis Signup and view all the answers

What organelle generates ATP for energy production?

Mitochondria Signup and view all the answers

During which phase of the cell cycle do chromosomes replicate?

Synthesis of DNA (S phase) Signup and view all the answers

What is the main function of microvilli in the small intestine?

Maximizing absorption of nutrients Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Highly active, carrying out their specific functions Signup and view all the answers

What is the function of lysosomes?

'Self-destruct' ageing cells Signup and view all the answers

Which ion is the principal extracellular cation?

Sodium (Na+) Signup and view all the answers

Which organelle is responsible for synthesizing lipids and steroid hormones?

Golgi apparatus Signup and view all the answers

What is the primary function of lysosomes within a cell?

Break down organelles and large molecules Signup and view all the answers

What is the main function of the cytoskeleton in a cell?

Guide the movement of materials Signup and view all the answers

Which ion is the principal intracellular cation?

Potassium (K+) Signup and view all the answers

What is the process called when the cell membrane engulfs larger particles like cell fragments or foreign materials?

Phagocytosis Signup and view all the answers

Which structure is involved in aerobic respiration and ATP synthesis?

Mitochondria Signup and view all the answers

What type of transport occurs when substances move down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

What is the main function of the nucleus within a cell?

Contain genetic material (DNA) and involved in metabolic activities Signup and view all the answers

What is the main function of ribosomes within a cell?

Synthesize proteins from amino acids Signup and view all the answers

Which phase involves further growth and preparation for cell division?

G2 phase Signup and view all the answers

What is the function of the Golgi apparatus in a cell?

Package proteins into vesicles and release them via exocytosis Signup and view all the answers

Which component of the plasma membrane creates a water-repelling central layer?

Cholesterol molecules Signup and view all the answers

What is the process called when substances move down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

What is the main function of the sodium-potassium pump in a cell?

Maintaining unequal concentrations of potassium ions on either side of the plasma membrane Signup and view all the answers

What is the name of the process involving the passive movement of water down its concentration gradient across a semipermeable membrane?

Osmosis Signup and view all the answers

What type of proteins form water-filled channels for very small, water-soluble ions to cross the membrane?

Membrane proteins Signup and view all the answers

Which process involves cells engulfing larger particles, such as cell fragments, foreign materials, or microbes?

Endocytosis Signup and view all the answers

What is the main function of facilitated diffusion in a cell?

Transferring substances by binding to specific sites on carrier molecules Signup and view all the answers

What is the name of the essential active transport mechanism found in all cells?

Sodium-potassium pump Signup and view all the answers

What does passive transport involve?

Moving substances down their concentration gradient through the plasma membrane without using energy. Signup and view all the answers

What distinguishes facilitated diffusion from other forms of passive transport?

The use of specialized protein carrier molecules to transfer substances by binding to specific sites. Signup and view all the answers

What is the primary function of osmosis?

To passively move water down its concentration gradient towards equilibrium across a semipermeable membrane. Signup and view all the answers

What function do membrane proteins serve in a cell?

To provide channels for electrolytes and non-lipid soluble substances. Signup and view all the answers

What is a characteristic feature of active transport?

The use of specialized protein carrier molecules to transfer substances by binding to specific sites Signup and view all the answers

What is the primary function of the sodium-potassium pump in a cell?

To maintain the intracellular environment by transporting Na+ out and K+ in Signup and view all the answers

What structure is involved in aerobic respiration and ATP synthesis?

Mitochondria Signup and view all the answers

What is the main function of microfilaments in a cell?

Providing structural support and enabling cell movement Signup and view all the answers

What type of cells line the small intestine and have microvilli for absorption?

Columnar epithelial cells Signup and view all the answers

What is the primary function of microfilaments in a cell?

Providing mechanical support and shape to the cell Signup and view all the answers

Which structure is involved in aerobic respiration and ATP synthesis?

Mitochondria Signup and view all the answers

What is the main function of cilia along the free borders of some cells?

Moving substances along the surface of the cell Signup and view all the answers

What is the primary function of the centrosome within a cell?

Organizing microtubules within the cell Signup and view all the answers

What does passive transport involve?

Movement of substances down their concentration gradient without using energy Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Cells are highly active, carrying out their specific functions Signup and view all the answers

What is responsible for packaging and transporting proteins to the cell membrane for export?

Endoplasmic reticulum Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Cells are highly active, carrying out their specific functions Signup and view all the answers

What is facilitated diffusion?

'Facilitated diffusion' involves movement down the concentration gradient with the help of carrier proteins Signup and view all the answers

What does the nucleus contain?

Chromosomes Signup and view all the answers

During which phase of the cell cycle do chromosomes replicate?

Synthesis of DNA (S phase) Signup and view all the answers

What organelle generates ATP for energy production?

Mitochondria Signup and view all the answers

Which organelle is responsible for synthesizing proteins from amino acids in a cell?

Endoplasmic reticulum Signup and view all the answers

What is the function of smooth endoplasmic reticulum (ER) in a cell?

Synthesizes lipids and steroid hormones Signup and view all the answers

Which ion is the principal extracellular cation in a cell?

Sodium (Na+) Signup and view all the answers

What is the process known as when cells engulf larger particles like cell fragments or foreign materials?

Phagocytosis Signup and view all the answers

What is the main function of the Golgi apparatus within a cell?

Packages proteins into vesicles and releases them via exocytosis Signup and view all the answers

What is the primary function of the cytoskeleton within a cell?

Provides internal support and guides movement of materials Signup and view all the answers

Which organelle is responsible for aerobic respiration and ATP synthesis in a cell?

Mitochondria Signup and view all the answers

What is the name of the process involving the movement of substances down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

What is the primary function of lysosomes within a cell?

Breaks down organelles and large molecules Signup and view all the answers

What structure contains genetic material (DNA) and is involved in metabolic activities within a cell?

Nucleus Signup and view all the answers

During which phase of the cell cycle do chromosomes replicate?

S phase Signup and view all the answers

What is the main function of microfilaments within a cell?

Provides internal support and guides movement of materials Signup and view all the answers

Which type of transport involves the movement of substances up their concentration gradient using chemical energy in the form of ATP and specialized protein carrier molecules?

Active transport Signup and view all the answers

What is the main function of the sodium-potassium pump in a cell?

Maintaining unequal concentrations of sodium and potassium ions on either side of the plasma membrane Signup and view all the answers

What is the process called when substances move down their concentration gradient across the membrane without using energy?

Passive transport Signup and view all the answers

Which process involves the passive movement of water down its concentration gradient towards equilibrium across a semipermeable membrane?

Osmosis Signup and view all the answers

What is the primary function of membrane proteins in the plasma membrane?

Serving as receptors and enzymes Signup and view all the answers

What is the main function of facilitated diffusion in a cell?

Transferring substances by binding to specific sites on carrier molecules Signup and view all the answers

What is responsible for packaging and transporting proteins to the cell membrane for export?

Golgi apparatus Signup and view all the answers

'Go' is a phase where cells may enter a resting stage. What is the main characteristic of cells in this phase?

Resting state with little or no cell division Signup and view all the answers

Which organelle generates ATP for energy production?

Mitochondria Signup and view all the answers

What is the proportion of plasma and the cell fraction in blood?

55% plasma, 45% cell fraction Signup and view all the answers

How much does blood make up of body weight in a 70 kg man?

About 7.5 liters Signup and view all the answers

What is the function of blood circulation?

Transporting oxygen, nutrients, and waste products Signup and view all the answers

How can blood cells and plasma be separated?

By centrifugation Signup and view all the answers

What is the main function of albumin in the blood plasma?

Creating plasma viscosity Signup and view all the answers

Where does haemopoiesis occur in adults?

All bones Signup and view all the answers

What is the primary function of electrolytes in the blood?

Carrying nutrients Signup and view all the answers

Which substance is responsible for transporting oxygen in the blood?

Globulins Signup and view all the answers

What are platelets responsible for in the blood?

Maintaining plasma osmotic pressure Signup and view all the answers

Where are most blood cells formed?

Lungs Signup and view all the answers

What is the primary function of plasma proteins in the blood?

Transporting hormones Signup and view all the answers

What is the main function of red marrow in bones?

Fat storage Signup and view all the answers

What is the primary role of hormones in the blood?

Transporting oxygen Signup and view all the answers

Which substance is essential for maintaining acid-base balance in the blood?

Carbon dioxide Signup and view all the answers

What is the main function of urea, creatinine, and uric acid in the blood?

Maintaining muscle contraction Signup and view all the answers

What substance is primarily responsible for maintaining normal plasma osmotic pressure in the blood?

Albumin Signup and view all the answers

What is the hormone that stimulates red blood cell production primarily in response to hypoxia?

Erythropoietin (EPO) Signup and view all the answers

What is the process called when ageing cells are programmed to 'self-destruct'?

Apoptosis Signup and view all the answers

Which component is responsible for packaging and transporting proteins to the cell membrane for export?

Golgi apparatus Signup and view all the answers

What is the lifespan of red blood cells?

120 days Signup and view all the answers

What determines different blood groups and triggers the production of antibodies in response?

Antigens (ABO and Rh) Signup and view all the answers

What is the primary role of iron from haemoglobin after red blood cell breakdown?

Reused Signup and view all the answers

Why were historical blood transfusions unsuccessful?

Incompatibility of blood types based on antigens Signup and view all the answers

What is the process called when substances move down their concentration gradient across the membrane without using energy?

Diffusion Signup and view all the answers

Which type of cells line the small intestine and have microvilli for absorption?

Columnar epithelial cells Signup and view all the answers

What is the term used for the process involving cells engulfing larger particles, such as cell fragments, foreign materials, or microbes?

Phagocytosis Signup and view all the answers

What is the principal extracellular cation in a cell?

Sodium (Na+) Signup and view all the answers

Which blood type individuals make neither anti-A nor anti-B antibodies?

Type AB Signup and view all the answers

Which white blood cells contain granules filled with toxic chemicals for eliminating parasites?

Eosinophils Signup and view all the answers

Which white blood cells are attracted to areas of infection by chemotaxins and engulf and kill bacteria by phagocytosis?

Neutrophils Signup and view all the answers

Which type of cells are important for adaptive immunity?

Lymphocytes Signup and view all the answers

Which white blood cells play a role in the immune response to allergens by releasing histamine and other chemicals?

Basophils Signup and view all the answers

What is the approximate percentage of people who are Rh-positive and do not make anti-Rh antibodies?

~85% Signup and view all the answers

Which white blood cells are the largest, making up about 1% of the blood volume, and contain nuclei and granules?

Lymphocytes Signup and view all the answers

Which type of blood individuals make both anti-A and anti-B antibodies?

Type O Signup and view all the answers

What is the primary function of red blood cells?

Transport of oxygen and some carbon dioxide Signup and view all the answers

What is the average lifespan of a red blood cell?

120 days Signup and view all the answers

Which vitamins are required for red blood cell synthesis and can be found in dairy products, meat, and green vegetables?

Vitamin B12 and folic acid Signup and view all the answers

What is the role of hemoglobin in red blood cells?

Allows red blood cells to carry oxygen Signup and view all the answers

What happens to oxyhemoglobin under low pH levels?

It releases additional oxygen for tissue use Signup and view all the answers

What is the consequence of iron deficiency with respect to red blood cells?

Inability to form hemoglobin Signup and view all the answers

What is the primary function of stem cells in red blood cell development?

Serving as the starting point for red blood cell production Signup and view all the answers

How does the shape of red blood cells contribute to their function?

Increases surface area for gas exchange Signup and view all the answers

What is the role of iron in hemoglobin?

Forms a necessary component of hemoglobin Signup and view all the answers

Study Notes

Ions: Potassium is the principal intracellular cation, sodium is the principal extracellular cation, and they tend to diffuse down their concentration gradients
Ion transport: Maintained by constantly pumping excess Na+ out of the cell in exchange for K+
Bulk transport: Particles too large to cross the cell membrane are taken in by pinocytosis or phagocytosis
Pinocytosis: Cell membrane engulfs fluid and particles, forming a vacuum that later becomes a membrane-bound vacuole
Phagocytosis: Cell membrane engulfs larger particles, such as cell fragments, foreign materials, or microbes
Organelles: Small, specialized structures within the cytosol that include the nucleus, mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, and cytoskeleton
Nucleus: Contains the body's genetic material in the form of DNA, and directs all metabolic activities
Mitochondria: Membranous, sausage-shaped structures in the cytoplasm that generate ATP for energy production
Ribosomes: Tiny granules composed of RNA and protein that synthesize proteins using RNA as a template
Endoplasmic reticulum: Extensive series of interconnected membranous canals that synthesize proteins, lipids, and steroid hormones
Golgi apparatus: Consists of stacks of closely folded flattened membranous sacs that package and transport proteins to the cell membrane for export
Lysosomes: Small membranous vesicles that contain enzymes involved in breaking down organelles and large molecules inside the cell
Cytoskeleton: An extensive network of tiny protein fibers that provides an internal support system and guides the movement of materials around the cell interior.
The phospholipid bilayer of the plasma membrane has hydrophilic heads on the outer surfaces and hydrophobic tails forming a central water-repelling layer.
Membrane proteins provide channels for electrolytes and non-lipid soluble substances, and perform various functions such as giving cell immunological identity and serving as receptors and enzymes.
Some membrane proteins form water-filled channels for very small, water-soluble ions to cross the membrane.
Membrane specializes in pumps that transport substances against their concentration gradient, importing pink particles into the cell and exporting blue particles out of the cell.
Passive transport occurs when substances move down their concentration gradient through the plasma membrane without using energy, such as water-soluble materials passing through water-filled channels and lipid-soluble materials dissolving in the lipid part of the membrane.
Facilitated diffusion is a passive process where specialized protein carrier molecules in the membrane transfer substances, such as glucose and amino acids, by binding to specific sites on the carrier.
Osmosis is the passive movement of water down its concentration gradient towards equilibrium across a semipermeable membrane, with waste material being extruded by the reverse process called exocytosis.
Active transport involves transporting substances up their concentration gradient using chemical energy in the form of ATP and specialized protein carrier molecules.
The sodium-potassium pump, an essential active transport mechanism found in all cells, maintains unequal concentrations of sodium and potassium ions on either side of the plasma membrane and uses up to 30% of cellular ATP requirements.
The phospholipid bilayer of the plasma membrane has hydrophilic heads on the outer surfaces and hydrophobic tails forming a central water-repelling layer.
Membrane proteins provide channels for electrolytes and non-lipid soluble substances, and perform various functions such as giving cell immunological identity and serving as receptors and enzymes.
Some membrane proteins form water-filled channels for very small, water-soluble ions to cross the membrane.
Membrane specializes in pumps that transport substances against their concentration gradient, importing pink particles into the cell and exporting blue particles out of the cell.
Passive transport occurs when substances move down their concentration gradient through the plasma membrane without using energy, such as water-soluble materials passing through water-filled channels and lipid-soluble materials dissolving in the lipid part of the membrane.
Facilitated diffusion is a passive process where specialized protein carrier molecules in the membrane transfer substances, such as glucose and amino acids, by binding to specific sites on the carrier.
Osmosis is the passive movement of water down its concentration gradient towards equilibrium across a semipermeable membrane, with waste material being extruded by the reverse process called exocytosis.
Active transport involves transporting substances up their concentration gradient using chemical energy in the form of ATP and specialized protein carrier molecules.
The sodium-potassium pump, an essential active transport mechanism found in all cells, maintains unequal concentrations of sodium and potassium ions on either side of the plasma membrane and uses up to 30% of cellular ATP requirements.
The phospholipid bilayer of the plasma membrane has hydrophilic heads on the outer surfaces and hydrophobic tails forming a central water-repelling layer.
Membrane proteins provide channels for electrolytes and non-lipid soluble substances, and perform various functions such as giving cell immunological identity and serving as receptors and enzymes.
Some membrane proteins form water-filled channels for very small, water-soluble ions to cross the membrane.
Membrane specializes in pumps that transport substances against their concentration gradient, importing pink particles into the cell and exporting blue particles out of the cell.
Passive transport occurs when substances move down their concentration gradient through the plasma membrane without using energy, such as water-soluble materials passing through water-filled channels and lipid-soluble materials dissolving in the lipid part of the membrane.
Facilitated diffusion is a passive process where specialized protein carrier molecules in the membrane transfer substances, such as glucose and amino acids, by binding to specific sites on the carrier.
Osmosis is the passive movement of water down its concentration gradient towards equilibrium across a semipermeable membrane, with waste material being extruded by the reverse process called exocytosis.
Active transport involves transporting substances up their concentration gradient using chemical energy in the form of ATP and specialized protein carrier molecules.
The sodium-potassium pump, an essential active transport mechanism found in all cells, maintains unequal concentrations of sodium and potassium ions on either side of the plasma membrane and uses up to 30% of cellular ATP requirements.
Erythropoiesis is the process of producing red blood cells (erythrocytes).
Oxygen levels play a role in regulating erythropoiesis: when oxygen levels are low, oxygen is released to tissues, increasing demand and production of red blood cells.
Erythropoietin (EPO) is the hormone that stimulates red blood cell production, primarily in response to hypoxia (low oxygen supply).
Hypoxia can result from various conditions including anaemia, low blood volume, poor blood flow, reduced oxygen content of inspired air, or lung disease.
Erythropoietin increases production of proerythroblasts and release of reticulocytes, speeding up their maturation to increase oxygen-carrying capacity.
Erythropoiesis is a homeostatic process, with red blood cell numbers remaining constant due to production and destruction.
Red blood cells have a lifespan of about 120 days and are broken down (haemolysis) by macrophages in the spleen, bone marrow, and liver.
Iron from haemoglobin is reused, while biliverdin is converted to bilirubin and excreted in bile.
Blood transfusions were historically unsuccessful due to incompatibility of blood types based on antigens (proteins) on red cell surfaces.
Antigens (ABO and Rh) determine blood groups, with different antibodies produced in response.
Individuals with AB blood type (approximately 55% of UK population) have neither A nor B antigens on their red cells and can receive blood from any group safely.
Individuals with O blood type (approximately 45% of UK population) have no A or B antigens on their red cells and can donate to any group safely.
The terms 'universal donor' and 'universal recipient' are misleading, as other antigen systems may cause incompatibility and transfusion reactions.
Cross-matching is required before transfusion to ensure compatibility between donor and recipient bloods.
Red blood cells (erythrocytes) are the most abundant type of blood cells, making up 99% of the total.
They are biconcave discs with a diameter of about 7μm and no nucleus.
Their main function is the transport of oxygen and some carbon dioxide.
The shape of red blood cells increases their surface area for gas exchange and allows fast entry and exit of gases.
They are flexible and lack intracellular organelles, allowing more room for hemoglobin.
The average human body contains about 30 trillion red blood cells, with a lifespan of around 120 days.
Red blood cell development starts with stem cells and takes about 7 days, during which they lose their nucleus and become incapable of division.
Vitamins B12 and folic acid are required for red blood cell synthesis and are found in dairy products, meat, and green vegetables.
Haemoglobin, a large molecule containing a protein and a pigmented iron-containing complex, allows red blood cells to carry oxygen.
An average red blood cell carries about 280 million haemoglobin molecules, giving it an oxygen-carrying capacity of over a billion oxygen molecules.
Iron, a necessary component of haemoglobin, is slow to absorb from the alimentary canal and can cause deficiency if losses exceed intake.
Oxygen binds reversibly to hemoglobin to form oxyhemoglobin, which releases oxygen readily under certain conditions.
Low pH levels cause oxyhemoglobin to break down and release additional oxygen for tissue use.
Low oxygen levels (hypoxia) cause oxyhemoglobin to release more oxygen to meet the body's needs.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge on the movement of potassium and sodium ions across the cell membrane and how their concentration gradients are maintained through active transport.