Structure and Function of the Cell 30 Carbohydrates

Structure and Function of the Cell

30 Carbohydrates and proteins are two types of macromolecules. Which functional characteristic of proteins distinguishes them from carbohydrates? 1. 2. 3. 4. Large amounts of stored information Ability to catalyze biochemical reactions Efficient storage of usable chemical energy Tendency to make cell membranes 0 hydrophobic

Text 30 1. 2. 3. 4. A B C 0 D

Discovery of the cell Smallest unit of life, Discovered by Robert Hooke 1665 Cell Theory: 1. All living things have cells 2. Cell is the basic unit of life 3. Cells only come from preexisting cells

Cell diversity and shape Variety of sizes Nerve cells shaped like fingers Most cells are round in shape Some cells change shape, white blood cells The shape of a cell depends on the cell membrane and it’s function

Size Cells are microscopic for the most part Some can be as large as 6 ft in giant algae The cell size is limited by the surface area of the cell membrane A cell can only grow so large then it will burst

Internal organization Organelles: structures in a cell that perform a specific function Eukaryotes: these are cells with membranebound organelles and a nucleus Prokaryotes: these are cells that do not have membrane-bound organelles or a nucleus

30 Living organisms can be classified as prokaryotes or eukaryotes. Which two structures are common to both prokaryotic and eukaryotic cells? 1. 2. 3. 4. Cell wall and nucleus Cell wall and chloroplast Cell membrane and nucleus Cell membrane and cytoplasm 0

Cell membrane “the bouncer” It is selectively permeable: only certain things may pass through Forms a bilayer: 2 layers of lipids like a sandwich 1. Maintains the shape of the cell and 2. protects it Fats and proteins are embedded in the phosholipid bilayer

Membrane lipids Phospholipids: have two ends on them that keep water and nutrients inside Form a bond that is difficult to break These lipids are vital to the cell’s survival Acts like a floating layer, constantly changing shape

Membrane proteins Do 3 things: 1. Hold the membrane together 2. Allow for channels to be made in the membrane 3. Act as receptors for hormones and other compounds

Fluid mosaic model Model of the cell membrane that shows it’s “dynamic ability”, how it is more like a liquid than a solid The patterns of lipids and proteins are always changing

Fluid mosaic model

Nucleus Controls the cell’s functions Houses the DNA Nuclelous: small part inside the nucleus where the ribosomes are made

Nucleus

Mitochondria Takes energy in food and turns it into chemical energy for the cell to use Has folds called “cristae”: increase surface area and creates more ATP Found more in muscle cells than any other

Mitochondria

Which cell type would contain the most mitochondria? 1. 2. 3. 4. Skin cell Fat cell Blood cell Muscle cell

Ribosome Most numerous organelle Found in all cells, prokaryote and eukaryote “Synthesize” ( make) proteins Found in cytoplasm and in rough ER

Enter question text. . . 30 1. 2. 3. 4. Cell membrane Chloroplast Mitochondria Ribosomes 0

t 30 1. 2. 3. 0 4. A B C D

The cell

Endoplasmic reticulum “ER” Rough: contains ribosomes, allows proteins to be made and to move throughout the cell Smooth: helps to synthesize lipids and remove toxins in liver cells

30 The endoplasmic reticulum is a network of membranes within the cell, and it is often classified as rough or smooth, depending on whethere are ribosomes on its surface. Which statement best describes the role of rough endoplasmic reticulum in the cell? 1. 2. 3. 4. It stores all proteins for later use It provides an attachment site for larger organelles. It aids in the production of membrane and secretory proteins. It stores amino acids 0 required for the

Golgi Apparatus Packages and ships proteins out of the cell. Located on or near the cell membrane Like the post office of the cell

Golgi Apparatus

Lysosome Contains digestive enzymes Breaks down materials and removes waste of the cell

Vacuoles and plastids (Plant Cells) ( Vacuoles: Contain digestive enzymes in plants. Can store toxins (poison ivy) Plastids: Contain chlorophyll so that plants can make food from sunlight Chlorophyll is usually a shade of green

Plastids (chloroplast)

Cytoskeleton Long protein strands found in the cell Provide support for the cell Help to maintain the shape of a cell Help in the movement of chromosomes when the cell divides Vital to the survival of the cell, if these proteins die the cell will loose it’s shape and die as well

Cilia and Flagella Assist in movement of the cell Cilia: Hair-like extensions on the outside of the cell membrane Flagella: whip-like tail on the cell membrane of cells Sperm cells use flagella to swim towards the egg cell Cilia are found in lung cells to sweep out debris

Flagella

Tissues and organs Similar cells that are grouped together form tissues 4 main types of tissues: muscle, nervous, connective and epithelial. Organs are a bunch of tissues that work together to perform a function. Example: the heart Many organs working together are an organ system: digestive system uses the stomach, intestines, kidneys etc. Organelles Cells Tissues Organ systems Organism