Human bio 2021
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Human bio 2021 - Leaderboard
Human bio 2021 - Details
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| 🇬🇧 | 🇬🇧 |
| Cell theory | All organisms are made of cells, which are the basic unit of life and arise from pre-existing cells |
| Cell membrane | Separates cell contents from outside the cell encloses cell contents and controls what enters and leaves is |
| Cytoplasm | Jelly like, watery material fills space between nucleus and cell membrane made from cytosol and organelles |
| Cytosol | The liquid part of the cytoplasm where most metabolic reactions occur controls osmotic pressure inside the cell dissolved salts and carbohydrates |
| Nucleus | Largest organelle in the cell oval/spherical |
| Nuclear pores | Allow large molecules, such as messenger rna to enter and leave the nucleus |
| Nuclear membrane | Separates nucleus from cytoplasm double membrane |
| Dna | Inside nucleus contains information that determines type of protein cell can make controls the structure and function of the cell nucleolus also plays a part in manufacturing proteins |
| Ribosomes | Small, spherical where amino acids are joined to make proteins can be free in cytoplasm or connected to other organelles |
| Endoplasmic reticulum | Membranes that form channels in cytoplasm used for storage, support, synthesis and transport in the cell rough has ribosomes, smooth doesn't |
| Structure and function of the body results from... | The activities of its cells |
| Golgi body | Flattened, stacked membranes, usually near the nucleus modifies proteins and packages them for secretion proteins produced at ribosomes pass through ER to the golgi body at the edges of the membranes, small sacs of proteins are formed, surrounded by a membrane called vesicles |
| Lysomes | Formed from golgi body, bound by membrane digestive enzymes break down large molecules vesicles that enter the cell and worn out organelles join with lysomes to be broken down |
| Mitochondria | Double membrane, outside surrounds mitochondrion inner membrane (cristae) folds inside where cellular respiration and some chemical reactions occur |
| Fcilia and flagella | Fine projections that can beat back and forth to move substances/molecules tiny 'hairs' are cilia, longer ones are flagella cilia in trachea flagella are on sperm |
| Cytoskeleton | Framework of protein fibers that shape cell and assist movement |
| Intwo types of cytoskeleton | Microtubules-hollow rods, hold/move organelles microfilaments-move materials around cell/move cell |
| Inclusions | Chemical substances not part of cell structure, found in cytoplasm eg. haemoglobin and pigment melanin |
| Fluid mosaic model explains what | Structure and function of the membrane (constantly moving and made up of many different molecules |
| Cell membrane composed of... | Phospholipids, form a bilayer |
| Structure of phospholipids | Hydrophobic head 2 hydrophilic tails |
| Properties of phospholipid bilayer | Held together by weak hydrophobic interactions in tails phospholipids and other materials move within bilayer fluid, can break and reseperate |
| Composition of the bilayer | Cholesterol and protein molecules embedded important for function integrity and stability of membrane |
| Functions of the cell membrane | Physical barrier-separates cell from surroundings regulate passage of materials-controls movement of materials entering and leaving sensitive to changes-first thing affected by changes outside cell supports cell-internal part of cell membrane is attached to cytoskeleton-connections between other cells membrane, providing whole tissue support |
| Simple diffusion | Molecules diffuse through the membrane along concentration gradient co2, o2, fatty substances, steroids, alcohol |
| Osmosis | Where solvent moves across a semi permeable membrane to where a solute is in higher quantity simple diffusion |
| Protein channels | Water soluble molecules diffuse through channel large molecules don't fit facilitated diffusion |
| Carrier meditated transport | One end open at a time specific to one particle become saturated, proteins can only process a certain amount in a certain time regulated by hormones |
| Facilitated diffusion | Along concentration gradient molecule attaches to a binding site on a specific protein, protein then changes shape to allow molecule to be released on the other side of the membrane carrier meditated transport |
| Active transport | Requires atp against concentration gradient similar to facilitated diffusion |
| Vesicular transport | Where droplet or solid enters or leaves cell |
| Endocytosis | Coming into the cell, membrane folds over and then pinches off pinocytosis-liquid phagocytosis-solid |
| Exocytosis | Out of the cell, fuses with membrane |
| Cell inputs | Oxygen, nutrients(lipids, amino acids, glucose), minerals, ions, vitamins, water |
| Cell outputs | Co2, toxic substances, proteins (hormones... |
| Epithelial tissue | Covering or lining tissue closely joined cells thin, flat, column, cube, etc. depending of the tissue line inside and/or outside of the heart, kidney, lungs |
| Epithelial tissue (epithelium) | Covering or lining tissue closely joined cells thin, flat, column, cube, etc. depending on tissue line inside and/or outside of heart kidney lungs |
| Connective tissue | Provides support, holds body parts together separated by large amounts of material not made from cells (matrix) |
| Connective tissue eg | Bone, cartilage, tendon, ligament, fat storage, blood |
| Types of muscular tissue | Skeletal, smooth, cardiac |
| Skeletal muscle tissue | Muscle attached to bones voluntary muscle stirated muscle |
| Smooth muscle tissue | So stirations involuntary stomach, intestines, iris, uterus |
| Cardiac muscle | Makes up most of the heart, pumps blood involuntary stirations |
| Nervous tissue | Neurons have long projections from the body of the cell when stimulated, messages are carried along projections from one part of the body to another nervous tissue found in brain, spinal cord, nerves |
| Metabolism def | All the chemical reactions that take place in the cell |
| Catabolic metabolism and example | Broken down to smaller molecules releases atp eg. digestion |
| Anabolic reaction def and eg | Built up to larger molecules requires atp eg. protein synthesis |
| Define nutrients | Any substance in food that is used for growth, repair or maintaining the body. |
| Six main groups of nutrients | Water carbohydrates lipids proteins minerals vitamins |
| Organic compounds | Have a carbon chain have a number of hydrogen atoms, can also include oxygen, nitrogen, sulfur, dna and rna |
| Carbohydrates | Main source of energy for the cell monosaccharides (mostly glucose) release energy poly/disaccharides broken down before entering cell eg. starch made of carbon, hydrogen, oxygen |
| Organic compounds eg | Carbohydrates, proteins, lipids |
| Lipids | Fats, oil and another important energy source broken down to fatty acids and glycerol contains one molecule of glycerol and 1-3 fatty acids glycerol breaks down similar to glucose |
| Proteins | Made of amino acids 100 or more amino acids in a single protein have characteristic shapes |
| Essential amino acids | Ones the body cant produce, so it must consume |
| Amino acids | Contain an amino group and a carboxylic acid group 20 different types found in proteins, each differing on structure of side chain. 2 bond to form a peptide bond shorter ones are called dipeptides and polypeptides |
| Inorganic compounds | Not based on carbon chain some reactions occur in water, some water takes part in the reaction |
| Inorganic compounds egs | Minerals vitamins |
| Minerals | May be part of enzymes, function as cofactors for enzymes or be a part of substances such as atp |
| Vitamins | Coenzymes for many chemical reactions of metabolism. |
| Enzymes | Biological catalysts used to speed up chemical reactions react with one specific molecule |
| Lock and key model | Enzyme is always complementary to shape of substrate, therefore the two will fit exactly to form the enzyme substrate complex |
| Induced fit model | When enzyme and substrate join, weak bonds are formed that change enzyme shape to create complementary shapes |
| Factors affecting enzyme activity | Shape and availability of active site concentration of enzyme/substrate temperature pH levels |
| Cofactors? | Used by enzymes to change shape of active site, so that enzyme can combine with substrate. eg. certain ions or non-proteins, minerals |
| Cellular respiration def | The process by which organic molecules are broken down in the cells to release energy for cellular activity |
| Cellular respiration can release energy from... | Glucose, amino acids, fatty acids, glycerol |