Specialised Cells Flashcards
What are Palisade mesophyll cells
Palisade mesophyll cells found in leaves are rectangular box-shaped cells that contain chloroplasts
The chloroplasts can absorb a large amount of light for photosynthesis.
They also move around in the
the cytoplasm to maximise the
amount of light absorbed.
What are Root hair cells
These cells are found at a plant’s roots, near the growing tip. They have long hair-like extensions called root hairs. The root hairs increase the surface area of the cell to maximise the movement of water and minerals from the soil into the plant root.
What are Sperm cells
Sperm cells are male gametes in animals. They have a tail-like structure called an undulipodium, so they can move. They also contain many mitochondria to supply the energy needed for this movement. The sperm head is three μm wide and four μm long. It is made up of an acrosome, which contains
digestive enzymes. These enzymes are released when the sperm meets the egg to digest the protective layer and allow the sperm to penetrate. The sperm’s function is to deliver genetic information to the egg
cell or ovum (female gamete). This is a ferti-location.
What are Egg cells
Egg cells, or ova, are the female gametes in animals. An egg cell is one of the largest cells in the human body and is approximately 0.12 mm in diameter. It contains a nucleus which houses the genetic material.
The zona pellucida is the outer protective layer/membrane of the egg. Attached to this is the corona radiata, which consists of two or three layers. Its function is to supply proteins needed by the fertilised egg
cell.
What are Red Blood cells
Red blood cells or erythrocytes are a bi-concave shape. This increases the surface area to volume ratio of an erythrocyte. They are flexible so that they can squeeze through narrow blood capillaries. Their function is to transport oxygen around the
body. In mammals, erythrocytes do not have a nucleus or other organelles. This increases space for the haemoglobin molecules inside the cell that carry oxygen.
What are White Blood cells
Neutrophils are a type of white blood cell, and they play an important role in the immune system. They have multi-lobed nuclei, which enables them to squeeze through small gaps when travelling to the site of infection. The cytoplasm holds lysosomes that contain enzymes that are used to digest pathogens that are ingested by the neutrophil.
