Cells & Cell Processes

Organization of living systems All matter made of atoms Atoms organized into molecules Molecules organized into cells (Living things are made of cells) Cells organized into tissues Tissues organized into organs Organs organized into organ systems Organ systems organized into organisms

Two types of cells Prokaryotic cells- Bacteria ONLY!!! Eukaryotic cells-All other living cells.

Prokaryotic Cells Lack nucleus and most other organelles (structure within cell – performs specific function) Include Eubacteria and Archaebacteria Archaebacteria – ancient bacteria Eubacteria – true bacteria Good bacteria and pathogenic bacteria

Eukaryotic cells Have nucleus and other organelles Ex. Nuclear Membrane and Mitochondria are membrane-bound organelles. FYI: Mitochondria have their own nuclei and can reproduce like in muscle tissue.

Organelles in Eukaryotic cells Nucleus – contains DNA; command center of cell Mitochondria – found in all eukaryotes – breaks down food molecules (i.e. – glucose) to release energy (cellular respiration) Equation for cellular respiration: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + ATP Ribosomes – where proteins are made Endoplasmic reticulum – path along which molecules move from one part of the cell to another Golgi apparatus – processes and packages substances produced by the cell

Lysosome – digests molecules, old organelles, and foreign substances Cilia and flagella – propel cells through the environment; move materials over cell surface Vacuole – storage of water, waste, and/or enzymes Microfilaments and microtubules – forms cytoskeleton of cell for support, movement, and division of cells Chloroplast – found in cells of plants and some protists – use energy in sunlight to make the sugar glucose (photosynthesis). Glucose fuels all life’s processes (plant and animal). Cell wall – (plants) supports/protects cell

Plant Cells have, and Animal Cells don’t Chloroplasts – organelle responsible for photosynthesis Cell Walls – a structure outside of the membrane to provide support Very large vacuoles to store extra water

This is a typical plant cell It contains a cell wall, chloroplasts, a very large vacuole. Why do plants need large vacuoles? ANSWER: This is where food and water are stored.

Specialized Cells Striated Muscle – skeletal muscle Smooth muscle - stomach Cardiac muscle Nerve cell

Specialized Cells Erythrocytes – red blood cells Monocytes – phagocytic white blood cells – fight bacteria Eosinophil – white blood cells – numbers rise when allergic reactions occur Lymphocytes – lymphatic system (white blood cells) B & T cells produce antibodies Neutrophils – most abundant white blood cells Basophils - help blood from clotting to quickly – helps promote blood flow to tissues

Specialized plant cells

52 Compared to annual rings of trees that have experienced years of sufficient rainfall, the annual rings of trees that have experienced a dry period will — F be softer G grow at a faster rate H be thinner J photosynthesize at a faster rate These would indicate more water, not less

Ways to maintain homeostasis Passive transport – no ATP used – Diffusion – Osmosis – Facilitated diffusion Carrier proteins Ion channels Active transport – ATP used – Carrier proteins Cell membrane pumps (sodium-potassium) – Endocytosis – exocytosis

Transporting into Cells - Passive movement from an area of high concentration to an area of low concentration is diffusion. The diffusion of water is called osmosis. Diffusion Osmosis is the diffusion of H 2 O

Types of Osmosis

What is Active Transport? Energy is used to move selected molecules into a cell, even if they are at a low concentration.

34 When a sea urchin egg is removed from the ocean and placed in freshwater, the egg swells and bursts. Which of these causes water to enter the egg? F Coagulation G Sodium pump H Active transport J Osmosis Means to clump together – Incorrect Sodium is not being moved – Incorrect The egg would not use energy to do this since it kills the cell. Salt Water Urchin Egg This is the movement of water from an area of high concentration (the fresh water) to low concentration (inside the Salt Water Urchin Egg)

6CO 2 + 6H 2 O  C 6 H 12 O 6 + 6O 2 This is photosynthesis Carbon dioxide Plus Water Produces Glucose And Oxygen

Plants do photosynthesis and cellular respiration.

Cellular Respiration C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O Occurs in mitochondria of all living things

Cellular Respiration

Fermentation Not enough oxygen present for the mitochondria to work then fermentation happens Alcoholic fermentation Lactic Acid Fermentation – (we do)

Viruses v. Bacteria Virusesv.Bacteria Size Type of Cell Living? Reproduction Very Small Larger, but still microscopic NOT A CELLProkaryote Non LivingLiving Invades host and makes copies of itself Binary fission (grow and split)

Virusv.Bacteria Treatment Prevention Benefits Example Drawing NONEAntibiotics Vaccines, good hygiene Vaccines, good hygiene NONE Helps with digestion (in stomach) Chickenpox, AIDS Streptococcus, e-coli, anthrax

Aids and HIV HIV stands for Human Immunodeficiency Virus It is the virus that causes AIDS HIV enters the body through the transmission of bodily fluids and attacks a specific type of immune cells called T Cells

T Cells T cells circulate in your body looking for cells that “don’t belong” They will attack and destroy invading bacterial cells and cancer cells When infected with HIV, the virus begins to reproduce within the T Cell (this destroys the T Cell)

The Onset of AIDS An infected person eventually reaches the point in which the body has too few T Cells to defend against invaders At this point the person has AIDS

AIDS AIDS stands for Acquired Immune Deficiency Syndrome AIDS is 100% fatal

Facts HIV is found in all body fluids (blood and semen- contain a much higher concentration of HIV) HIV is most commonly spread through: – sexual contact, contact with contaminated needles, mother to child during pregnancy, child birth and breast feeding HIV is not spread through: – Kissing,Shaking hands,Water fountains, Sneezing, or Insects