Cells and Transport Flashcards
What is the function of the nucleus?
Control centre, contains genetic information
What’s the function of the cytoplasm?
Liquid gel in which most of the chemical reactions take place.
What’s the function of the cell membrane?
Semi-permeable controls movement of material in and out of cell.
What’s the function of the cell wall?
Support and protection of plant cell.
What’s the function of mitochondrion?
‘Powerhouse’ of the cell (produces ATP by respiration)
What’s the function of the ribosome?
Production of proteins.
What’s the function of the chloroplast?
Uses energy to make food by photosynthesis.
What’s the function of the permanent vacuole?
Stores food, water and waste in plants.
What’s the function of the lysosomes?
Special type of vacuole that breaks down old cell parts and large molecules.
What’s the function of the endoplasmic reticulum (ER)?
Transport of chemicals and proteins within cells.
What’s the function of the Golgi?
Modifies proteins to make them functional and transports proteins within cells.
What’s the function of the cytoskeleton?
Support structure within cells (skeleton) and made of proteins.
What’s an organ?
Collection of tissues that perform a specific function within an organism.
What’s an organism?
A living being.
What’s an organelle?
A functional structure within a cell.
What’s an organ system?
A collection of organs that perform a specific function within an organism.
What’s a tissue?
A collection of connected cells that perform a similar function within an organism.
What’s a cell?
The structural unit of an organism may exist as independent life.
Nerve cell function
Transmits nervous stimuli.
Nerve cell adaption
Synapses and neurotransmitter. Can be very long. Myelin sheath (insulation).
Ciliated cell function.
e.g. Clears airways.
Ciliated cell adaptation
Cilia that beat backwards and forwards to move material.
e.g. Sweep mucus with trapped dust and bacteria along to throat.
Sperm cell function
Fertilisation of egg
Adaptation of sperm cell
Small with tail for movement.
Lots of mitochondria.
Acrosome with enzymes to digest egg membrane.
Genetic information (23 chromosomes)
Egg cell function
Fertilisation
Egg cell adaptation
Large and bulky. Contains yolk (food strorage) for developing embryo. Genetic information (23 chromosomes)
Red blood cell function
Transport of oxygen
Red blood cell adaptation
No nucleus (more space for haemoglobin).
Biconcave shape.
Contains haemoglobin which binds oxygen.
White blood cell function
Destroys pathogens
White blood cell adaptation
Some produce antibodies.
Some have flexible cytoskeleton so that they can change shape quickly to engulf bacteria.
Muscle cell function
Contraction
Muscle cell adaptation
Long and flexible.
Lots of mitochondria.
Palisade cell function
Photosynthesis
Palisade cell adaptation
Lots of chloroplasts
Tightly packed, elongated.
Root hair cell function
Uptake of water and minerals.
Root hair cell adaptation
Have root hairs (increases surface area)
Large permanent vacuole.
Close to xylem (water transport)
Guard cell function
Control opening of stomata
Guard cell adaptation
Take up and release water by osmosis to open and close stomata.
Thickened cell wall.
What is diffusion?
- the movement of gases or dissolved molecules from an area of high concentration an area with low concentration
- the movement of molecules down a concentration gradient
Cell membranes are…
selectively permeable - oxygen, carbon dioxide, glucose, amino acids and ions can go through, not starch or proteins
The larger the concentration gradient, the…
the faster the rate of diffusion
The larger the surface area, the…
the faster the rate of diffusion
The smaller the diffusion distance, the…
the faster the rate of diffusion
The hotter the temperature, the…
the faster the rate of diffusion, as the molecules have more kinetic energy
What is osmosis?
• the movement of water molecules from an area of high water/low solute concentration to an area of low water/high solute concentration across a selectively permeable membrane
What does isotonic mean?
Same concentration
What does hypotonic mean?
Lower concentration
What does hypertonic mean?
Higher concentration
What is facilitated diffusion?
The movement of molecules from high to low concentration with the help of a channel or carrier protein
What is passive transport?
The movement of molecules through cell membranes down a concentration gradient without the use of energy by the cell (diffusion, facilitated diffusion, osmosis)
What is active transport across membranes?
The movement of molecules though all membranes against a concentration gradient at the cost of energy and with help of a carrier protein
When water enters plant cells by diffusion they become…
Turgid
How do vaccinations provide protection from further infection?
• Vaccinations result in the making of memory cells, which enable future antibody production to the pathogen to occur much more quickly.
What are two differences between osmosis and diffusion?
- Osmosis only refers to the movement of water molecules, whereas diffusion can refer to the movement of any type of molecule.
- Osmosis always happens across a selectively permeable membrane, whereas diffusion can take place without the presence of a selectively permeable membrane.
