Human Bio Year 11 Atar Semester 1

Diaphragm

Contracts and flattens downwards which increases the volume of the chest and lungs. Sheet of muscle separating the thoracic cavity from the abdominal cavity

Vesicular Transport

Active transport, movement of substances across a cell membrane, in vesicles. -Exocytosis -Endocytosis

Anaerobic Respiration

After Glycolysis when pyruvic acid molecules don't have enough oxygen and so lactic acid is produced. Enzymes are in the cytosol and so it occurs in the cytosol.

Pharynx

Aka the throat, air from nasal cavity can pass through here. Back of mouth caavity, by moving upwards and backwards, tongue pushes food into the pharynx for swallowing.

Trachea

Aka the windpipe; carries air to and from the lungs. Lined with a mucus membrane and cells with cilia. Cilia bent to move mucus and trapped particles upwards.

Pleural Membrane

Covers surface of the lungs and lining inside of the chest.

Larynx

Organ of voice, air passes through going to and from the lungs. Contains the vocal cords which can vibrate to produce sound.

Active site

Part of enzyme that combines with the substrate

Types of Cell Transport

Passive - diffusion - osmosis - carrier mediated transport (facilitated diffusion) Active - vescular transport & carrier mediated transport (active transport)

Facilitated Diffusion

Passive transport of molecules along a concentration gradient. Carrier proteins change shape.

Carrier Proteins

Are specific and only bind to a particular molecule. E.g carrier protein that binds only to glucose molecules. Not even simple sugars that make up glucose can bind with protein.

Atrioventricular Valves

Attached to tendous cord on ventricle wall. Prevents backflow of blood from the ventricles to the atria. -Tricuspid Valve -Bicuspid Valve

Structure of Cell Membrane

Similar for organelle membrane and cell membrane. Lipids 2 layers called a bilayer Lipids with a phosphate group Have a head and tail Each phospholipid molecule has a water loving and water hating end. 2 layers with heads on outside and tails on inside Phospholipids can move and change positions so they are said to be fluid

RNA

Single chain of nucleotides containing sugar ribose

Anabolism

Small molecules being built up into larger molecules requiring energy

Formed Elements

Solid part of blood. 45% of blood stream. - Erythrocytes - Leucocytes - Thrombocytes

Coronary Circulation

Supports cardiac muscle, circulation to the heart tissue, supplying it with blood.

Endocytosis

Taking materials into the cell by vesicular transport -pinocytosis -phagocytosis

Exocytosis

Taking materials out of the cell, by vesicular transport.

Epithelial tissue

Thick layered, cuboidal cells. Stretchable, e.g urinary bladder. Collapsed or distended forms

Left Ventricle

Thick muscular wall for pumping blood into the aorta and out of the body

Alveoli

Tiny air sacs. Gas exchange occurs here. Surrounded by a network of blood capillaries. Bronchioles end in groups of air sacs. Make up most of the lungs. Huge surface area, clusters of sacs with 1 cell thick walls.

Circulatory system main function

Transport of nutrients and gases around the body. Heart, arteries, veins, capillaries, lymphatics.

Osmosis

Type of diffusion Diffusion of water molecules (human body) or liquid solvent from a low solute or high solvent concentration to a high solute or low solvent concentration, across a differentially/semi permeable membrane until dynamic equilibrium is reached. Sugar, starch and proteins cannot diffuse through membrane.

Bronchioles

Very fine tubing with walls of smooth muscle.

Stroke Volume

Volume of blood forced from a ventricle of the heart with each contraction

Urea

Waste product of protein when it is broken down into amino acids.

Hydrophobic Tail

Water hating tails that prevent water from flowing through it. Each phospholipid has a tail.

Hydrophilic Head

Water loving heads that allows water through it

Ventilation

aka breathing enables efficient exchange of gases between the blood and alveoli, in the lungs. Process by which air is moved into and out of the lungs via air pressure. Lower air pressure in the lungs forces air into them and vice vera.

Carbaminohaemoglobin

carbon dioxide attached to haemoglobin to form this ionic compound

Channel Proteins

form a channel through the membrane and have central pores that allow ions, water and other small soluable molecules through. Small in diameter,

Systems

group of organs that work together to perform a major function

Involuntary muscle

involuntary muscle. no striations; smooth muscle. attached to organs

Skeletal

makes up muscles attached to bones. Voluntary muscle. Striped or striations.

Organs of the respiratory system

nose mouth pharynx larynx trachea primary bronchi secondary bronchi tertiary bronchi bronchioles alveoli lungs

Stored energy in ATP

some of the energy of cellular respiration is stored in the bond between the ADP molecule and the 3rd phosphate group. This bond is easier broken then bonds 1&2. The ADP molecule can be reused.

Formation of ATP

when inorganic phosphate group joins to a molecule of adenosine diphosphate (ADP), the phosphate groups in ATP are joined by high energy bonds.

How concentration gradient affects the rate of diffusion

Higher concentration gradient will increase the rate of diffusion.

Matrix

Non-cellular material.

Heart Rate

Number of times heart beats per minute

Factors Altering Enzyme Activity

1) Concentration of enzyme (↑) so rate of reaction (↑) to the point of all substrate occupied 2) Substrate concentration (↑) so rate of reaction (↑) to the point of all substrate occupied 3) (↑) Products of reaction will (↓) rate of reaction as less enzymes are combining with substrate 4) temperature (↑) chemical reactions also (↑) to point (40`c) where protein molecule bonds fall apart optimum temp is about 36.7`. 5) sensitive to pH of substrate. Optimum pH level 6) requires presence of co-factors which change shape of active site, before they can catalyse a chemical reaction. 7) Presence of enzyme inhibitors which slow or stop emzyme activity.

Why Lungs are suited to gas exchange

1) alveoli give the lungs a huge surface area so that large amounts of gases can be exchanged in a relatively short time period. Estimates of number of alveoli in the lungs vary. Total surface area of 50m - 80m^2 2) each alveolus is well supplied with blood vessels, so that as much blood as possible can undergo gas exchange. Flow of blood maintains a concentration gradient in the lungs and the blood stream. 3) membrane on alveolus wall is 1 cell thick. Gas molecules don't have far to travel when moving into and out of the blood. 1 layer of cells, 1 micrometer thick. 4) lungs positioned deep inside body preventing excess evaporation of pleural fluid. Important that the alveoli be covered with a moist membrane so gases can be dissolved and then diffuse into blood stream. Gases cannot diffuse into the blood unless they are dissolved in fluid 5) lung volume can be changed by movements of the respiratory muscles so that air can be made to flow into and out of the lungs. Constant changing of volume ensures there is a concentration gradient in the blood and lungs

Functions of the cell membrane

1) physical barrier; separates cytoplasm from the intercellular fluid. Important as composition of extracellular fluids are different to the intercellular fluid. 2) Regulation of the passage of materials; controls the movement of materials into and out of the cell 3) Sensitivity; is the first part of the cell affected by changes in the intercellular fluid and has receptors sensitive to molecules in the intercellular fluid. 4) support; internal part of cell membrane attaches to microfilaments of the cells cytoplasm, giving support to the whole tissue.

Functions of the Blood

1) transporting O₂ and nutrients to cells 2) transporting CO₂ and wastes away from cells 3) maintaining pH of body fluids 4) distributing heat and maintaining body temp 5) water balance and ion concentration of body fluids 6) Protection against diseases, pathogens and toxins 7) clotting when vessels are damaged preventing blood loss.

Lungs

2 Lungs take up whole chest cavity except the space between them occupied by the heart and blood vessels. Covered by pleural membrane outside lungs. excretion of CO₂ produced by all cells during cellular respiration.

Bronchi

2 primary bronchi branch from the trachea. They then divide into secondary and tertiary bronchi.

Energy from cellular respiration

60% released as heat 40% forms compound adenosine triphosphate (ATP)

Transport of CO₂

8% dissolved in plasma as CO₂ gas 22% combines with haemoglobin to form carbaminohaemoglobin 77% carried as bicarbonate ions in plasma.

Circulatory System

Bodies main internal transport system. Link between the cells inside the body which have certain requirements and the external environment that supplies the requirements.

Pulmonary Vein

Brings oxygenated blood to the heart from the lungs.

Arteries

Carry blood away from the heart under high pressure. Generally carry blood that is oxygenated, except the pulmonary arteries. Walls are thick layers of cells with elastic walls.

Capillaries

Carry blood between cells, microscopic, capillaries supply each individual cell (2-3 cells away) with nutrients and enables cells to remove metabolic wastes. I cell thick wall. Elastic walls, blood is under a higher pressure than arteries.

Veins

Carry blood to the heart under low pressure. Generally carry deoxygenated blood, except the pulmonary veins. Contains values. Inelastic walls.

Blood Vessels

Carry blood to tissues, from the heart, and back to the heart. Blood is pumped by heart into blood vessels. -Capillaries -Arteries - Arterioles -Veins - Venules

Pinocytosis

Cell membrane folds creating an invagination around the extracellular fluid and it becomes a vesicle in the cell.

Phagocytosis

Cell membrane forms a fold around the solid molecules and forms a ventricle.

Muscle tissue

Cells are long and thin aka muscle fibres. Can respond to stimulus by contracting and becoming short and fatter. - Cardiac - Skeletal - involuntary

Metabolism

Chemical Reactions that take part in the organsim. concerned with maintaining homeostasis between energy release and energy utilisation. - Anabolism - Catabolism

Co-enzymes

Co-factors, non-protein molecules, organic molecules E.g Vitamins

Synthesis

Combining of small molecules to make larger molecules aka anabolism or protein synthesis from amino acids. Require both matter and energy

Aerobic Respiration

Complete breakdown glucose to CO₂ and H₂O. Pyruvic acid is converted to these products. Occurs in the mitochondria. Enzymes are attached to the internal membrane. After Glycolysis, pyruvic acid molecules enter the mitochondria where they undergo 2 more reactions; - Citric Acid Cycle - Electron Transport System

Nasal Cavity

Contains projections that increase internal surface area. Filters, warms and moistens air before entering the lungs. Contains smell receptors, acts as a resonating chamber for speech sounds, Hairs and mucus trap dust and microbes.

Carrier Mediated Transport

Doesn't rely on concentration gradient Active and passive depending on the concentration gradient. Proteins bind to the molecules which are then transported and help their passage across the membrane. - Facilitated diffusion - Active transport

DNA

Double chain of nucleotides, joined by set combinations of bases.

Phospholipid Bilayer

Embedded in the phospholipid bilayer are cholesterol and protein molecules. Enables water molecules to diffuse into and out of cells. Prevents too much water from entering at once.

Respiratory System

Excretion of CO₂ and inhalation of air which then removes waste products such as CO₂ from the blood and allows O₂ to diffuse into the blood stream where it is then used by cells. Supplies oxygen to body circulation.

Glycolysis

First phase in the breakdown of glucose. No oxygen is required. 1 molecule of glucose is broken down into 2 molecules of pyruvic acid.

Epiglottis

Flat of tissue that during swallowing closes off the trachea so food and liquid cannot enter the lungs.

Pleural Fluid

Fluid in between the pleura membranes. Holds the lungs against the chest wall and allows the lungs to slide along the wall when breathing.

Diffusion

Gas or liquids passive movement of molecules along a concentration gradient from high particle concentration to low, until dynamic equilibrium is achieved.

Tissues

Group of cells with a similar function and specialisations that work together to carry out a particular task. Epithelial Connective Muscle - cardiac - skeletal - involuntary Nervous

Organs

Group of several tissues working together to perform a particular function.

Septum

Heart Muscle separating left and right sides of heart

Intercostal muscles

In between the ribs. Moves the ribcage upwards and outwards, then downwards and inwards. Increases volume of the chest cavity and therefore the volume of the lungs when breathing in.

Co-factors

Ions, non-protein molecules that change the shape of the active site so that an enzyme can combine with the substrate. - Co-enzymes

Catabolism

Large Molecules are broken down into smaller ones releasing energy

Cell membrane

Larger layer surrounding cell forming an outer boundary separating fluid tissue from matter in the cytoplasm. Double lipid layer and proteins.

Epithelial Tissue

Lining tissue. function is secretion, protection, absorption, filtration. Cells are joined closely together e.g skin outer layer - Simple cubodial - Simple Squaremonus - Simple columnar - Stratified squaremonous - Pseudostratified columnar - Traditional epithelium

Plasma in blood

Liquid part of blood. The matrix of blood vessels. Clear pale yellowish liquid 55% of blood stream. 91% of plasma is water, 9% is dissolved nutrients, steroids, gases, plasma, proteins, wastes and organic and inorganic substances e.g Ca²⁺ or Na⁺

Nervous tissue

Made of neurons, has ability to conduct electrical impulses from one part of the body to another. Long projections from cells. E.g Brain, Spinal cord, relay, motor, sensory neurons.

Aorta

Main artery that takes blood to all parts of the body. (except lungs)

Superior Vena Cava

Major vein bringing blood to the heart from the head and upper body.

Inferior Vena Cava

Major vein bringing blood to the heart from the lower body and legs.

Cardiac muscle

Makes up most of the heart. Involuntary striated and has branches.

Substrate

Molecules on which an enzyme acts. Occurs because emzyme and substrate have complimentary characteristics; shape and structure

Connective tissue

Most abundant and widely distributed of the tissues. Connective tissues perform a variety of functions including support and protection. Cells are not close together and surrounded by matrix. E.g loose connective tissue, fat tissue, bone, lymph node tissue,

Semilunar Valves

Prevent back flow of blood from the arteries to ventricles. Consists of 3 cups that are thin membranes. -Semilunar Valve -Aortic Semilunar Valve

Inspiration

Proccess of taking air into the lungs. Aka inhalation. Pressure in lungs must be less than the atmospheric so there is net movement into the lungs. To decrease lung pressure, volume of lungs is increased. 1) diaphragm contracts becoming long and flat, moving downwards, increasing volume of the thoracic cavity. 2) intercostal muscles contract pulling ribs upwards and outwards, increasing volume of the thoracic cavity 3) as pleural fluid adheres to the pleura of the thoracic cavity, the lungs expand with the expanding thoracic cavity 4) increased lung volume means that there is a lower air pressure inside lungs than atmospheric outside the body. 5) net movement of air by diffusion along the concentration gradient into the lungs, via nasal cavity, mouth, pharynx, larynx, trachea and bronchi primary, bronchi secondary and tertriary, bronchioles and then into the alveoli until air pressure becomes equal.

Cellular respiration

Process by which organic molecules, taken in as food, release energy for cell activity. E.g glucose from complex carbohydrates, amino acids from protein breakdown, fatty acids or glycerol from lipids.

Lactic Acid

Produced during glycolysis when oxygen isn't available.

Pyruvic acid

Produced during glycolysis. It is then broken down in cellular respiration or converted to lactic acid no oxygen

Enzymes

Proteins that allow chemical reactions to take place at normal body temperature. Enzymes reduce activation energy so they are catalysts. Targets 1 substrate per enzyme. Are renewable after completing reaction.

Heart

Pump that pushes the blood around the body. Located in the middle of the chest cavity. Conical in shape, the heart is the size of a closed human fist. Enclosed in the pericardium.

Right Ventricle

Pumps blood to the lungs, it's walls are thinner than the left ventricle wall because not as much force is required to push blood to the lungs and back.

Left Atrium

Receiving chamber for blood from the lungs. Pushes blood into the left ventricle.

Right Atrium

Receiving chamber for deoxygenated blood that has been through the capillaries of the body.

Catabolic Reactions

Release energy from the breakdown of complex molecules.

Anabolic Reactions

Require energy to build up simple molecules or store energy.

Active Transport

Requires energy Against concentration gradient