Specialized Cells

Red Blood Cells

• Hemoglobin - to bind and transport oxygen

• No nucleus - to pack more hemoglobin

• Biconcave shape - more surface area for faster diffusion of gases

Ciliated Epithelial cells

• Goblet cells secrete mucus that traps dust and bacteria

• Cilia on the surface beat to move fluids and particles up the trachea

• Also found in the fallopian tube to sweep the egg towards the uterus for fertilisation

Microvilli

• Increase surface area for absorption

• One cell thick to increase diffusion

• Network of blood capillaries to absorb glucose and amino acids and nutrients

• Lacteal absorbs fats

Nerve Cells

• Axon is very long

• Has dendrites at each end to carry impulses

Sperm Cell

• The head contains a haploid nucleus; when fusing egg cell = diploid zygote

• acrosome contains digestive enzymes that break down the jelly coat egg cell membrane

• middle piece is packed with mitochondria for energy to swim and fertilize

• tail allows it to swim

• sperm are the smallest in the body so millions are made

Egg cell

• the cytoplasm contains nutrients for the growth of the early embryo (placenta)

• It has a haploid nucleus. When fusing egg cell= diploid zygote

• jelly coat harden after fertilization so no other sperm cell will enter

Palisade cell

• packed with cholorplasts

• absorbs light energy for photosynthesis

• found in leaves

Root Hair cell

• root hair increases surface area for greater absorption of water and minerals

• Thin cell walls for faster diffusion

• mitochondria for active transport to release energy to absorb minerals

Guard cells

• guard cells open and close the stomata

• in night, it is closed to prevent loss of water

• open - turgid/swollen closed - flaccid/ shrunken

xylem

• xylem transports water and minerals

• xylem is dead cells

• thick walls are stiffened with lignin to withstand water pressure

• pores to allow water to enter and leave the xylem

phloem

• transports sugars

• living cells