Biology 7.1 and 7.2 Quiz
Lysosomes
(clean-up crew or digestive unit) They are small organelles filled with enzymes. Break down lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell. Remove "junk" and mainly found in animal cells.
Cytoplasm
(floor) Fluid (gel-like) portion of the cell outside the nucleus. It provides a surface for organelles.
Nucleus
(main office) a large membrane-enclosed structure that contains genetic material in the form of DNA and controls many of the cell's activities. The nucleus is surrounded by the Nuclear envelope.
Golgi apparatus
(packaging and distribution) It is a stack of flattend membranes. Proteins from the Rough ER travel here. The GA modifies, sorts, packages, tags for storage, or transport, distribution out of the cell. it does the modifying in membrane bound vesicles.
Cytoskeleton
(steel, cement beams, Support) Helps the cell maintain its shape and is also involved in movement. It is a network of protein filaments. (conveyor belt, flagella, and cillia)
Endoplasmic Reticulum
(the highway) Internal membrane system - Eukaryotic Assembles lipids for cell membranes and assembles proteins and other materials that are exported from the cell
The Cell Theory
1. All living things are composed of cells 2. Cells are the basic units of structure and function in living things 3. New cells are produced from existing cells
Explain vacuoles in plant cells.
Large central vacuole that allows pressure changes to increase rigidity to support heavy leaves and flowers (90% volume)
Explain vacuoles in animal cells.
Less prominent, less frequent
Explain the importance of proteins.
Living things are always modifying new molecules, especially proteins. Proteins catalyze chemical reactions and make up important structures of the cell.
Ribosomes
Make proteins which is the most important job. RNA are found throughout the cytoplasm. Ribosomes follow coded instructions from the DNA. Bone marrow is highly active in protein synthesis.
Smooth ER
No ribosomes, enzymes that have special tasks
Cell Walls
Only in prokaryotes. Rigid, supports, shape, protects the cell. It is outside the cell membrane. It has pores to allow water, oxygen, carbon dioxide, and other substances to pass
Chloroplast
capture the energy from sunlight and convert it into food that contains chemical energy in photosynthesis. Surrounded by 2 membranes. Green pigment-chlorophyll
What organelles capture and release energy?
chloroplasts and mitochondria
DNA
coded instructions for making proteins and other important molecules. DNA exists in the chromatin
What microscope do we use in class?
compound light microscope
chromation
condenses before cell division becomes chromosomes
What do both prokaryotic and eukaryotic cells have?
cytoplasm, DNA, cell membrane, ribosomes
Rough ER
has proteins, ribosomes on the surface, membrane proteins, proteins carried in vesciles
Who was Anton Van Leewenhoek?
he used a powerful lens as a magnifying instrument, saw tiny living organisms in a drop of pond water
What 2 parts is a cell divided into?
nucleus and cytoplasm
explain vacuoles in fungi
prominently occur (25% volume)
cell
smallest unit of any organism
Vescicles
store and move materials between cell organelles, as well as to and from the cell surface.
Vacuole
store materials like water, salts, proteins, and carbohydrates. They are large and sac-like membrane enclosed.
organelles
structures found with a cell "little organs" (Eukaryote) understanding each organelle helps understand the whole cell
Hydrophilic
water loving
What does a eukaryotic cell have?
DNA in the nucleus, larger and more complex, dozens of structures, highly specialized. Plants, animals, fungi
Who was Robert Hooke?
English lens maker. First person to observe cells. (Cork-chambers "cells")
Endosymbitoic theory
Eukaryotes that undergo photosynthesis have both mitochondria and cholorplasts.
Nucleolus
Found inside the nucleus and produces ribosomes
Mitochondria
Almost all cells have them. They convert chemical energy from food into compounds that are more convenient for the cell to use. Outer and Inner membrane encloses mitochondria.
What does a prokaryotic cell have?
Cell wall; smaller, not complex, no nucleus, less complex ribosomes. Cytoplasm with no membrane-bound organelles, unicellular. Bacteria
What are the two types of an Electron Microscope?
Transmission- 2-D very thin slices. Scanning- 3-D images of specimens surface
What is the difference between a vesicle and vacuole?
Vesicles are smaller
Hydrophobic
Water fearing
What is a micrograph?
a photo of an object seen through a microscope
Cell membrane
all cells. It has a double layered sheet, lipid bilayer. The cell membrane regulates what enters and leaves the cell and so protects and supports the cell.