Essays Flashcards
(24 cards)
The part played by the movement of substances across cell membranes in the functioning of different organs and organ systems.
Plasma membranes and movement across
Gaseous exchange system/ lungs
Transpiration/root/stem
Lungs cystic fibrosis
The part played by enzymes in the functioning of different cells, tissues and organs.
Action of enzymes Enzyme properties Nutrient cycles Replication of DNA Homeostasis
Movements inside cells.
Plasma membranes and movement across Protein synthesis Movement through ER and Golgi Cell division and chromosome movement Water movement in plants/xylem Neurones and synaptic vesicles Actin and myosin Electron transport chains
Transfers through ecosystems
Photosynthesis – energy transfer Respiration – energy transfer Carbon cycle Nitrogen cycle Food chains Ecological pyramids Eutrophication
The transfer of substances containing carbon between organisms
Food chains and feeding relationships:
• plants producers; idea of food chains as feeding relationships; with transfer energy ; in substances containing carbon
Digestion and absorption:
• digestion/hydrolysis of large carbon-containing compounds; by enzymes; producing small/soluble compounds
Transport of organic molecules in and out of cells/across exchange surface:
• organic molecules (including sugars and amino acids) cross cell membranes; by facilitated diffusion; active transport; which requires ATP from respiration; involving carrier proteins and/or enzymes
The transfer of substances containing carbon between organisms AND THE ENVIRONMENT
Carbon cycle
carbon enters biotic by photosynthesis; leaves biotic by respiration
Photosynthesis
light-independent reaction ; carbon dioxide reacts with RUBP
Respiration
(Krebs cycle)
Exchange surfaces
large surface area - alveoli
How are the shapes of cells related to their functions?
Blood . white cells - phagocytes engulfing bacteria
Nervous system - receptors -cone/rod cells containing pigment
Muscle - contain rows of sarcomeres, leads to contraction in length
root hair cell - increases SA for absorption of water and mineral ions
Bacterial cells - flagellum rotates
Negative feedback in living organisms
principle of negative feedback - restore a system to the norm
importance in homeostasis; principles of detection of change
thermoreceptors and hypothalamus in detection; heat loss and heat gain centres
regulation of blood glucose; roles of receptors in pancreas, secretion of insulin or glucagon
control of heartbeat; roles of chemoreceptors and pressure receptors
The process of osmosis and its importance to living organisms
definition
effects on cells; turgity and support
role in movement of water from soil to leaves in plants
Energy transfers which take place in living organisms
ATP - synthesis from ADP and P; role as an energy source
photosynthesis - generation of ATP
respiration - synthesis of ATP associated with electron transfer chain
uses of energy in biological processes - e.g. active transport or muscle contraction
Cycles in biology
Nitrogen cycle Carbon cycle Krebs cycle Light-independent reactions Cardiac cycle Cell cycle - stages of mitosis DNA replication – semiconservative replication Predator / prey life cycles
Condensation and hydrolysis and their importance in biology
Synthesis of proteins, carbohydrates and lipids from monomers
1. Large molecules are important in the structure and functioning of cells
Hydrolysis of proteins, carbohydrates and lipids from monomers
- Large molecules are important in the structure and functioning of cells
- Digestion of food
Condensation and hydrolysis of other substances
- DNA, RNA and protein synthesis
- The role of ATP
Ways in which different species of organisms differ from each other
Genes and environmental factors influence variation between individuals
Evolution/Speciation
ecosystem (niches)
different types of haemoglobin
The transfer of energy between different organisms and between these organisms and their environment.
Photosynthesis - uses energy from sunlight
Food chains and food webs
Respiration produces ATP
Temperature control uses energy
The causes of variation and its biological importance
Gene mutation = addition; deletion ;substitution; effect on alleles; effect on polypeptide / protein
Sexual reproduction = crossing over; independent assortment; random fusion
Environmental = nutrients; disease; light; temperature
Biological importance = enables adaptation; natural selection ; speciation; evolution
The process of diffusion and its importance in living organisms
The process itself
Gaseous exchange in lungs
The uptake of water by roots = osmosis
Importance of Molecular shape
1) Carbohydrates – storage / structural / glycoprotein etc.
2) Proteins – levels of structure / enzymes – specificity / properties
3) Lipids – phospholipids
4) Interaction with receptors
5) Drugs
6) Antibodies (antibody – antigen complex)
7) Hormones – seconds messenger / direct action
8) Neurotransmitters – synapses.
ATP and its roles in living organisms
nature of ATP and its importance as energy source Production of ATP - respiration Production of ATP - photosynthesis Uses – active transport Uses - muscle contraction
Describe how the structures of different polymers are related to their functions.
structural molecules, e.g. cell walls, carbohydrates and proteins
informational molecules e.g. Enzymes and DNA as genetic material
associated with storage e.g. carbohydrates
Hydrogen bonds and their importance in living organisms
passage of water through a plant and cohesion tension
The structure of proteins, starch and cellulose
structure of enzymes
structure of nucleic acids, DNA
How nitrogen-containing substances are used by living
organisms.
Proteins as biological molecules
Enzymes and enzyme action
Haemoglobin and the exchange of respiratory gases
The use of membrane proteins in the nervous system
DNA and protein synthesis
Chlorophyll, NADP and photosynthesis
ATP and respiration
Why the offspring produced by the same parents are different in appearance
Genes influences phenotype Gene mutation Environment variation Meiosis, independent segregation Random fertilisation of gametes
Apart from causing disease, describe how bacteria may affect the lives of other
organisms
Gene technology
Carbon cycle
Nitrogen cycle and nitrogen fixation
Describe the structure and function of membranes
Plasma membrane: Diffusion Facilitated diffusion Active transport Osmosis
Structure:
Fluid mosaic model
