bio paper 1 key words Flashcards
(34 cards)
Define osmosis
when molecules of a solvent pass through a semipermeable membrane from a less concentrated solution into a more concentrated one.
define active transport
the movement of dissolved molecules in or out of a cell through the cell membrane, from place of lower concentration to a place of higher concentration
define diffusion
when molecules move from an area of high concentration to an area of low concentration
equation for photosynthesis
6CO2 + 6H2O-C6H12O6+6O2
process of mitosis in 4 steps
DNA is replicated – each chromosome makes an identical copy of itself, forming two sister chromatids.
Chromosomes line up in the centre of the cell.
Chromatids are pulled apart to opposite ends (poles) of the cell.
The cell divides – the cytoplasm splits (cytokinesis), forming two genetically identical daughter cells.
whats a pathogen
a microorganism that causes disease
equation for magnification
image size/actual size
what are the main types of enzymes and what do they do
Amylase breaks down starch → sugars
Protease breaks down proteins → amino acids
Lipase breaks down lipids → fatty acids + glycerol
how are monoclonal antibodies produced in 5 steps
A mouse is injected with an antigen to stimulate production of antibodies.
B-lymphocytes (white blood cells that make antibodies) are collected from the mouse.
These are fused with tumour cells (which divide rapidly) to form hybridoma cells.
The hybridoma cells are selected and cloned to make many cells that all produce the same antibody.
The antibodies are then collected and purified for use.
test for starch
iodine on food goes from orange/brown to blue/ black
test for sugars
benedicts solution goes from blue to brick red
test for proteins
biurets solution goes blue to purple
test for lipids
ethanol then add water, it will turn from clear to cloudy white
3 main stages of drug testing
Preclinical Testing
Done in a lab using cells, tissues, and animals.
Tests for toxicity, dosage, and how the drug works.
Clinical Trials – Phase 1
Tested on a small number of healthy volunteers.
Checks for safety and side effects.
Clinical Trials – Phase 2/3
Tested on patients with the illness.
Tests for effectiveness and finds the best dose.
xylem
a tissue of higher plants that carries water and dissolved materials upward, lies deeper inside the plant than the phloem
phloem
plant vascular tissue that transports organic nutrients, primarily sugars and amino acids, throughout the plant
anaerobic respiration
Respiration without oxygen, releasing less energy
aerobic respiration
Respiration with oxygen, releasing lots of energy.
prokaryotic cells
a simple single-celled organism with no nucleus e.g. bacteria
eukaryotic cell
have a nucleus enclosed within the nuclear membrane and form large and complex organisms e.g. plants and animals
stem cells
cells with the potential to develop into many different types of cells in the body
what causes coronary heart disease
caused by the buildup of plaque in the coronary arteries, leading to a narrowing or blockage of blood flow to the heart
what is an epithelial cell
the most abundant cells in the body, forming linings and coverings of surfaces like skin, body cavities, and blood vessels. They play a crucial role in protecting the body from external factors, regulating fluid and solute movement, and acting as a barrier.
root hair cells
specialized plant cells in roots that absorb water and mineral ions from the soil. They have elongated, thin projections that extend into the soil, increasing the surface area for efficient absorption.
