B1 Flashcards
characteristics of living things
Movement-change in position in space
Respiration-break down nutrients and release energy
Sensitivity-ability to detect and respond to changes
Growth-permanent increase
Reproduction-making more of the same kind
Excretion-removal of waste products
Nutrition- as the taking in materials for energy
Vacuole
Fills most space. Fluid helps maintain turgor pressure within the cell
Nucleus
Contains genetic information
Chloroplasts
Found in the cytoplasm, contains chlrophyll. Site of photosynthesis
Cell membrane
Semipermeable layer, controls the movement of substances in and out of the cell
Mitochondria
Site of aerobic respiration, provides energy
Ribosomes
Makes protein
Cytoplasm
Gelatinous liquid that fills the inside of the cell, site of chemical reactions
Ciliated cells
Function: movement of mucus in the trachea and bronchi
Special adaptations:
- Have “hair” like structures (cilia)(to sweep mucus and pathogens away from lungs
- Increases surface area; works like villi in intestines
Root hair cells
Function: absorption of water and mineral ions from soil
Adaptation:
- elongated shape, large surface area to maximise osmosis
- thin cell wall to decrease distance for diffusion
Palisade mesophyll cells
Function: main site of photosynthesis in a leaf
Adaptation:
- packed withc hloroplasts
- tall shape, large S.A
- thin shape, lot of cells can fit at the top of the leaf
Neurones
Function: conduction of electrical impulses
Adaptations:
- long fiber
Red blood cells
Function: carries oxygen throughout the body
Adaptation:
- biconcave shape, large S.A for efficient diffusion of gases
- contains haemoglobin that binds with oxygen to carry it
- no nucleus, more space for haemoglobin
Sperm and egg cells (gametes)
Function: reproduction
Adaptations:
- Sperm has a tail (helps swimming)
- Sperm has enzyme (in the head of the cell to digest the jelly coat of egg)
- Egg has energy store (for respiration)
Magnification formula
image size/actual size
Osmosis
Movement of water through a semi-permeable membrane from an area of high to low water potential.
Diffusion
Net movement of particles from high to low concentration, stops when equilibrium is reached
factors influencing diffusion
- Larger surface area, greater rate of diffusion
- At higher temperatures, particles move faster, greater rate of diffusion
- Diffusion distance, shorter=greater diffusion
- Size of diffusing particles - inversely proportional, the smaller is the size of the molecule, the higher is the rate of diffusion.
Hypotonic, isotonic, hypertonic
Hypotonic: Weak solution, lower solute conc. Water is sucked in
Isotonic: Same concentraction
Hypertonic: Strong solution, higher solute conc. Water is sucked out
Active transport
Movement of particles against the concentration gradient using ATP, how root hair cells absorb mineral ions
