Cells PDF - Biology

What are cells? Basic life units Structural, functional entities Form tissues, organs Present in all organisms Microscope - Onocular lens Single-eyepiece microscope Magnifies small samples Common in basic studies Useful for cellular observation Mitochondria Energy-producing organelles Found in eukar...

What are cells? Basic life units Structural, functional entities Form tissues, organs Present in all organisms Microscope - Onocular lens Single-eyepiece microscope Magnifies small samples Common in basic studies Useful for cellular observation Mitochondria Energy-producing organelles Found in eukaryotic cells Perform cellular respiration ATP generation sites Unicellular/Multicellular - examples Unicellular: Single-celled organisms Exam- ple: Bacteria, amoeba Multicellular: Many-celled organisms Example: Humans, plants Animal cell vs. Plant cell Animal lacks cell wall Plant has chloroplasts Animal lacks large vacuole Both are eukaryotic cells What are organelles? Cellular structures performing functions Include nucleus, mitochondria Found in eukaryotic cells Work together for cell survival Organelles in fungal cells Nucleus, mitochondria present Cell wall of chitin Lacks chloroplasts Has vacuoles for storage White blood cells/Red blood cells White: immune defenders Red: oxygen transporters White: fight infections Red: hemoglobin-rich, biconcave Nerve cells Neurons transmitting signals Long, specialized structures Enable communication, response Found in nervous systems Specialized plant cells types Root cells absorb nutrients Guard cells regulate gas Xylem transports water Phloem transports sugars Animal cell organelles Nucleus, mitochondria, ribosomes Endoplasmic reticulum, Golgi apparatus Lysosomes, peroxisomes, vacuoles Cytoplasm, plasma mem- brane What are living things? Organisms with biological processes Growth, reproduc- tion essential Respond to environment stimuli Include animals, plants, microbes What is bacteria? Unicellular prokaryotic organisms Lack membrane-bound organelles Found in various environments Can be helpful or harmful What is a virus? Non-living infectious particles Require hosts for reproduction Contain DNA or RNA Cause diseases in organisms Chloroplast Photosynthesis organelle in plants Contains chlorophyll pigment Converts sunlight to energy Absent in animal cells Cellular respiration Process of energy extraction Occurs in mitochondria mainly Converts glucose to ATP Essential for cellular function Photosynthesis Energy conversion in plants Occurs in chloroplasts Uses sunlight, water, CO2 Produces oxygen, glucose Types of muscles Skeletal: voluntary movement Smooth: internal organs’ control Cardiac: heart muscle contractions Specialized in different functions 1 Body tissue Groups of specialized cells Types: epithelial, connective, muscular Perform specific body functions Form organs and systems 2