Cells, Tissues And Organs Flashcards
Biological unit - simplest unit of life
Cell
Describe different levels of organisation multicellular organisms
Lots of cells make up tissues
Lots of tissues make up organs
Lots of organs working together make up organ systems
Lots of organ systems working together make up an organism
Give examples of specialised cells in animals
Red blood cell
Nerve cells
Egg cell
Sperm cell
Give example of specialised cells in plants
Root hair cells
Palisade cells
Red blood cell function and specialisation
To carry oxygen
Large surface area for oxygen
Biconcave shape
Haemoglobin that binds to the oxygen to form oxyhaemoglobin
Nerve cell function and specialisation
To carry nerve impulses to different parts of the body
Long
Connections at each end
Can carry electrical signals
Egg cell function and specialisation
To provide nourishment for the embryo before implantation in the womb
Large
Cytoplasm contains nutrients and energy rich yolk which will nourish the embryo before implantation
Sperm cell function and specialisation
To reach the female egg and fertilise it
Long tail for swimming
Head containing chemicals to help penetrate the female egg
Root hair cell function and specialisation
Absorbing water and minerals from the soil
Large surface area- because of extension of cytoplasm
Thin cell wall for minerals to pass through
Palisade cell function and specialisation
To absorb sunlight needed for photosynthesis
Large surface area
Many chloroplasts - containing chlorophyll for photosynthesis
Phloem - made up of sieve tubes and companion cells
State function and specialisation
Transports sugar around a plant
End walls have holes to allow sugar to be transported to the next cell
Xylem vessels function and specialisation
Support of water transport up the plant
Hollow tube
Wall strengthened by lignin
Lignin deposited as rings or spirals allowing expansion and contraction
