Biology Lab Tests for Glucose, Starch, and Fat

Biological Molecules

Glucose test: uses Benedict's solution, results in a color change from blue to brick red
Starch test: uses iodine, results in a blue color
Fat test: uses ethanol, results in a cloudy white emulsion
Protein test: uses Biuret solution, results in a mauve color

Micrograph Calculations

When a scale line is given, actual size = image size (mm) x scale (value on line) / length of scale line (mm)
Magnification = length of scale line (mm) / scale (value on line)

Eutrophication

Process of excess growth of plant life and bacteria in a body of water, depleting oxygen
Causes: overuse of fertilizers, runoff of phosphates and nitrates into waterways
Effects: algae growth, decreased oxygen levels, death of aquatic life

Cells

Basic information: cells are the smallest living units, discovered by Robert Hooke in the 1600s
Cell theory: all living things are made of cells, all cells come from pre-existing cells
Characteristics of all cells: surrounding membrane, protoplasm, organelles, control center with DNA and RNA

Organelles

Make up the "cellular machinery" of the cell
Two types: derived from membranes, bacteria-like organelles
Examples: centrioles, lysosomes, chloroplasts, mitochondria

Prokaryotic and Eukaryotic Cells

Prokaryotic cells: bacteria and archaea, no membrane-bound nucleus
Eukaryotic cells: include protists, plants, animals, fungi, nucleus is membrane-bound

Animal and Plant Cells

Animal cell: centrioles, lysosomes, vacuoles
Plant cell: chloroplasts, cell wall, vacuoles

Plasma Membrane

Surrounds cell, contains all cell contents
Made up of phospholipid bilayer and proteins
Phospholipid: made up of phosphoric acid and lipid molecule

Transport

Passive transport: movement from high to low concentration, does not require energy
Active transport: movement against concentration gradient, requires energy
Types of transport: diffusion, osmosis, facilitated diffusion, active transport

Cell Walls and Cytoskeleton

Cell walls: found in plants, fungi, and protists, surrounds plasma membrane
Cytoskeleton: made up of filaments and fibers, provides mechanical support and helps move substances around the cell

Lysosomes and Vacuoles

Lysosomes: contain digestive enzymes, aid in cell renewal and breaking down foreign substances
Vacuoles: membrane-bound storage sacs, more common in plant cells

Endocytosis and Exocytosis

Endocytosis: movement of large material into the cell, two types: bulk phase and receptor-mediated
Exocytosis: movement of large molecules out of the cell, process is opposite of endocytosis

Organic Compounds

Carbohydrates: made up of C, H, and O, examples: monosaccharides, disaccharides, polysaccharides
Lipids: made up of C, H, and O, examples: fats and oils, provide energy and insulation
Proteins: made up of C, H, O, N, and sometimes S, P, and Fe, provide structure and function

Mitosis and Cytokinesis

Mitosis: process of cell division that maintains the number of chromosomes
Cytokinesis: division of the rest of the cell into two daughter cells
Errors in mitosis can result in cell death or abnormalities such as cancer### Phases of Mitosis
Mitosis consists of 5 phases: interphase, prophase, metaphase, anaphase, and telophase.
These phases are part of the process of karyokinesis, which includes early-stage telophase.
Late-stage telophase is part of cytokinesis.
Each phase involves different proteins performing specific roles to divide genetic material.

Interphase

No cell division occurs during this phase.
The cell grows and becomes fully mature.
DNA begins to replicate.

Prophase

Chromatin shortens and thickens to form chromosomes.
Chromosomes consist of chromatids and centromere.
Microtubules organize to form mitotic spindles.
Nucleolus and nuclear membrane/envelope begin to disappear.

Metaphase

Chromosomes arrange themselves at the cell's equator (metaphase plate).
Mitotic spindles assist in this arrangement.
Centromeres attach to the mitotic spindles.

Anaphase

Each pair of chromosomes is pulled apart into chromatids.
Centromeres divide.
Chromatids are now called daughter chromosomes and are identical to the mother chromosomes.
Spindle fibres contact and shorten, pulling chromosomes to opposite poles of the cell.

Telophase

Early telophase:
- Spindle fibres disappear.
- Chromosomes deconstruct into chromatin.
- A new nuclear envelope begins to form around the chromatin.
- Cell membrane begins to cleave (cell cleavage) in preparation for cytokinesis.

Cytokinesis

The cell membrane is pinched off to form 2 separate compartments.
Cytoplasm and organelles are divided between the daughter cells.
At the end, the membrane fuses and cuts the two daughter cells off from each other.

Characteristics of Daughter Cells

Daughter cells have identical DNA and the same amount of cytoplasm and organelles.

Mitosis Definitions

Nucleus: location of DNA in a cell.
Nuclear envelope: membrane that separates the nucleus from the cytoplasm.
DNA: long molecule containing genetic blueprints for cell behavior.
Chromatin: loosely bundled coil of DNA.
Histones: proteins that hold DNA together in chromatin.
Chromosome: highly organized form of chromatin.
Chromatids: 1 half of a chromosome containing the same genetic information.
Centromere: bundle of proteins connecting the 2 chromatids to form a chromosome.

Mitosis in Plants

Mitosis occurs in special meristematic cells.
Growth occurs in length (radicle, plumule, or buds) and thickness (division in cambium tissue in stem).

Mitosis in Animals

Mitosis takes place in special organ tissues.
Examples include embryonic development, basal layer of epidermis, long bones, and lymph glands.

Benefits of Mitosis

Mitosis enables growth processes (length, thickness, metamorphosis, and increase in natural aging).
Mitosis allows for the repair and replacement of damaged/worn-out cells.
Mitosis is a method of reproduction in unicellular organisms (binary fission).