Cells Review List Test Thursday 1/28 Levels of Organization
Most Complex Organism Group of organ Person, systems working Dog, together Flower Organ System Group of organs Circulatory system, working together Nervous system, Digestive system Organ Group of tissues Heart, working together Brain, Stomach Tissue Group of cells working Blood, together Nerves, Connective tissue Cell Basic unit Red blood cell, Group of organelles Epithelial cell, working together Neuron Least complex Organelle Specialized structures Nucleus, found in cells Mitochondrion, Vacuole
Cell Theory Contributions of scientist… Robert Hooke 1665 First discovered cells by looking at cork. Named the “little room” he saw “cells”.
Anton Van Leeuwenhoeke 1673 Made improvements to the microscope when observing pond scum.
Matthias Schleiden 1838 Examined plant cells and concluded that all parts of plants are composed of cells.
Theodore Schwann 1839 Examined animal tissue and concluded that all parts of animals are composed of cells.
Rudolf Virchow 1858 Observed that cells come from existing cells.
The three parts of the cell theory are: 1. All living things are composed of cells. (Schleiden & Schwann) 2. Cells are the basic units of structure and function for living things. (Schleiden & Schwann) 3. All are produced from existing cells. (Virchow)
ALL cells can…. Obtain energy (organelles responsible: chloroplast and mitochondrion) Get rid of waste (organelles responsible: lysosome and cell membrane) Grow and reproduce (organelles responsible: centriole and nucleus)
Cell Organelles Organelle structures are designed to help them complete their functions. Structure is the shape or location. Function is its job. Example: tire structure – round, rubber; function – roll and grip road Plant cells are elongated for stacking up; the cells are more box-like and rigid, with larger vacuoles for storing water. Blood cells are round so they can travel through blood vessels and deliver oxygen and nutrients to the other cells of the body. Muscle cells are elongated for contracting and pulling on bones
Cell Membrane – found in both plant and animal cells Function: controls the passing of materials in and out of the cell; gets rid of waste Structure: surrounds the cytoplasm
Nucleus – found in both plant and animal cells Function: acts as the control center of the cell Structure: holds the DNA/chromosomes
Cytoplasm – found in both plant and animal cells Function: suspend other organelles Structure: jell-like liquid that fills the cell
Mitochondria – found in both plant and animal cells Function: release ATP energy Structure: double membrane organelle with inner folds
Vacuole – found in both plant and animal cells Function: Storage site for water, nutrients, and waste Structure: much larger in plant cells
Cell Wall – found in ONLY plant cells Function: supports and protects Structure: rigid; surrounds cytoplasm in plant cells
Chloroplasts – found in ONLY plant cells Function: site of photosynthesis (how a plant makes food) Structure: Green; contains chlorophyll; stacks of disc inside
Lysosome – found in some plant and animal cells Function: removes waste, and digest old cell parts Structure: small, circular, contains enzymes
Cilia – found in unicellular organisms and some animal cells Function: used for motion Structure: tiny hair-like projections on the outside of certain cells
Flagellum – found in unicellular organisms and some animal cells Function: used for motion Structure: a long whip-like structure on the outside of certain cells