BIO 101 Chapter 4

What is the size of a Prokaryotic cell?

2-8 Micrometers?

What is a Prokaryotic Cell?

A cell without a true nucleus

What is the Cell Membrane covered with?

A rigid cell wall, often with flagella for locomotion.

What are Plasmodesmata? and what does it allow?

Cell junctions (channels) between adjoining plant cells. It allows Water and other small molecules to readily pass between cells.

What do Anchoring Junctions do?

Cells are attached with fibers, but materials pass along spaces between the cells. Capillaries. They Leak

What does the Tight Junction do? (Animal Cells)

Cells are bound tightly together forming a leak proof sheet.

What are Communicating Junctions?

Channels that allow water and other materials to flow between neighboring cells

What is the Microtubule an important component for?

Cilia and Flagella

Where are tight junctions common in?

Common in the digestive system for obvious reasons

What does a Mitochondria do?

Convert food energy into cell energy (ATP).

What does Chloroplats do?

Converts solar energy into chemical energy

In the Prokaryotic cell, what is free to roam in its Cytoplasm?

DNA and Ribosomes.

What type of membrane does a Chloroplast have?

Double

What is the function of Contractile Vacuoles?

Excrete excess

What does Cristae mean?

Folds in membrane that increases surface area

What is the function of a Food Vacuole?

Form itself around food particles

Where are Chloroplasts found?

Found in plants

What are the Muscle and Nerve Cells sizes?

Long and Slender

What is in the Eukaryotic cell?

Many Organelles, membranous and nonmembranous. Internally complex

What is a Lysosome?

Membrane-enclosed sacs (vacuole) of digestive enzymes

What are Vacuoles?

Membranous sacs of various sizes and functions often formed by the ER or Golgi.

What is the characteristic of the Smooth ER?

No ribosomes so it has a smooth appearance.

What are the Organelles of the Cell?

Nucleus, Ribosomes, Rough ER, Smooth ER, Golgi Apparatus, Lysosomes, Contractile Vacuoles, Central Vacuoles, Chloroplasts, Mitochondria

What are the functions of the Rough ER?

Protein synthesis and membrane production

What is a Membrane Protein?

Protein that is embedded in the lipid bilayer

What are the characteristics of Ribosomes?

Ribosomes are the site of protein synthesis. Ribosomes occur outside the nucleus and are found bound to membranes or free floating in the cytoplasm.

What does it the Microtubule do?

Serves as a tract for movement of organelles and choromosomes.

What is the size for Red Blood Cells?

Small...apparently

What are the two internal membrane within the cell?

Smooth Endoplasmic Reticulum and Rough Endoplasmic Reticulum.

Why is Cell Size important?

The important point is that the surface area to the volume ratio gets smaller as the cell gets larger. Thus, if the cell grows beyond a certain limit, not enough material will be able to cross the membrane fast enough to accommodate the increased cellular volume.

What could happen if the Cell is too big?

There is not enough memebrane to support the increased volume of the cell. Cells remain small or die from lack of nutrients, oxygen, or an accumulation of waste.

What are characteristics of Plant Cells?

They are encased in a rigid cell wall, this provides support and protection for the cell. Although the cell was is thick, plant cells aren't totally isolated from each other.

What is the function of the Cilia?

They function in locomotion for certain organisms, and function in movement of materials in most organisms.

What are Cell Size for Egg Cells?

Usually large and carry nutrients.

What is the size for a Eukaryoric Cell?

Usually larger than prokaryotes 10-100um.

What is a characteristic of a Flagella?

Usually longer and few. 1-3, and function solely in locomotion

What is the characteristic of the Cilia?

Usually shorter and more numerous than flagella.

What is the smallest cell?

Bacteria is the smallest cell. 1-.1 Micrometers

What are the 3 points to the Cell Theory?

1. All Organisms are composed of 1 or more cells 2. The cell is the basic unit of organization 3. All cells arise from preexisting cells

What are 2 Energy Converting Organelles?

1. Chloroplasts 2. Mitochondria

What are the 4 functions of Lysosomes?

1. Digests food in food vacuoles 2. Destroys bacteria and other disease agents 3. Destroy damaged/old organelles 4. Selective cell death, embryonic development

What are the characteristics of a Mitochondria?

1. Double Membrane 2. Site of Cellular Respiration 3. Cristae

What are the 3 types of Vacuoles?

1. Food Vacuoles 2. Contractile Vaculeos 3. Central Vacules

What is the function of the Membrane Protein?

1. Give the cell identiy - Protein on the Surface Cell Membranes 2. Site of attachment of the cytoskeleton 3. Chemical Receptors 4. Movement of substances across the cell membrane

What are the 5 Characteristics of a Nucleus?

1. Most easily seen organelle 2. Genetic Control Center of the Cell 3. Double perforated membrane (nuclear envelope) 4. Nucleolus manufactures Ribosomes 5. DNA is stored in the Nucleus

What are three things the Golgi Apparatus does?

1. Receives and modifies substances produced by the rough ER 2. Exports materials from the cell, or to locations within the cell 3. Abundant in glandular cells

What are the 4 Membrane functions?

1. Separate the cells from its environment 2. Control the passage of molecules (selective permeability) 3. Partition cell functions into organelles 4. Provides surfaces for reactoin

What are the three types of cell junctions?

1. Tight Junctions 2. Anchoring Junctions 3. Communicating Junctions

What is an example of a Prokaryotic cell?

Bacteria

What is the characteristic of the Rough ER?

Has ribosomes embedded in the membrane. It has a rough appearance.

What are the functions of the Smooth ER?

Lipid Synthesis Detoxification of Drugs Storage of Ca+ ions; muscle contraction

What is a Microtubule?

One type of protein making up the cytoskeleton.

What is the Hydrophilic head of a membrane? and what is the tail?

Phosphate and Fatty Acid

What is the main component of membrane?

Phospholipds.

Animals cells only have what kind of membrane?

Plamsa membrane.

What is in the Plant Cell?

Plasma membrane that is surrounded by a cell wall, central vacuole.

What is the function of the Central Vacuole and where is it found? how much cell space does it take?

Store of nutrients, Water, Toxins. Found in plants Takes up to 1/2 the cells total volume.

What is the characteristic of a Microtubule?

Straight, hollow tubes made of globular proteins

What makes the Cell Size?

Surface Area to Volume Ratio limits the size of cells.

What are the characteristics of a Phospholipid?

The head is hydrophilic and the tail is hydrophobic