Untitled Flashcard Set

Concept 1 Study Review

Vocabulary

1. Cell: the smallest unit that can live on its own and that makes up all living organisms and the tissues of the body

2. Organelle: a small structure in a cell that is surrounded by a membrane and has a specific function

3. Macromolecule: very large molecules made of many smaller parts joined together

4. Nucleotide: the base building block of nucleic acids like DNA & RNA. It has three parts: 5-carbon sugar, phosphate group, and a nitrogen-containing base

5. Fatty acid: the building blocks of the fat in our bodies and in the food we eat

6. Monosaccharide: the simplest form of carbohydrates or single sugar molecules

7. Amino acid: small organic molecules that link together to build proteins

8. Enzyme: special proteins made by living cells that act as biological catalysts. They speed up chemical reactions in the body without getting used up or changed in the process

9. Catalyst: a substance that speeds up a chemical reaction without being changed itself

10. Active site: a small specific pocket or cleft on the surface of an enzyme or protein

11. Differentiation: the process where a basic, unspecialized cell changes into a specific mature cell type with a unique job
    
    
    

1. List the characteristics that all living things share

• Made of cells (basic unit of life)

• Respond to stimuli: a stimulus triggers a reaction or response from the body

• Able to grow and reproduce: living things grow in size and produce offspring

• Use energy (have a metabolism)

• Contain genetic material: possess either DNA or RNA
  
  

2. Describe the role of each organelle in the overall function of the cell

• Cytoplasm: jelly-like fluid inside the cell that holds everything in place

• Cell (Plasma) Membrane or Phospholipid Bilayer: Permeable barrier that controls what goes in and out of the cell to maintain homeostasis

• Cytoskeleton: Network of threadlike protein fibers (microtubules, intermediate filaments, microfilaments) that supports the cell, maintains its shape, helps with motility, and regulates biochemical activities

• Centrioles: Made of microtubules, 2 centrioles are referred together as centrosomes. They appear during cell division and help the cell divide by pulling chromosomes apart during anaphase

• Cilia: short, numerous projections that move fluid across the cell’s surface

• Flagella: longer, fewer projections (1-3) that move the entire cell through extracellular fluid

• Nucleus: contains genetic material (DNA), when it appears threadlike it is considered to be chromatin, chromatin condenses into 46 chromosomes in body cells (sex cells like egg and sperm only have 23 chromosomes) Genes are sections of chromosomes that code for proteins. It is surrounded by a nuclear envelope/membrane with pores that control what goes in and out. The nucleolus is in the center and is where ribosomes are formed. Its function is to protect the DNA that controls the activities of the cell.

• Ribosomes: made of rRNA and proteins; site of protein synthesis. Located on Rough ER or floating in the cytoplasm

1. Rough ER ribosomes: make proteins for export out of the cell

2.  Cytoplasm ribosomes: make proteins for use inside the cell

• Rough ER: network of sacs hugging the nucleus with ribosomes on the surface. Makes and packages proteins into vesicles to send to the Golgi apparatus. (Vesicles act like mini-carts that transport proteins around and out of the cell)

• Smooth ER: Network of sacs attached to Rough ER with NO ribosomes. Makes lipids, chemically modifies small molecules, breaks down glycogen, and stores Ca2+

• Lysosomes: contain hydrolytic enzymes to break down food, bacteria, and old cell parts, and perform apoptosis (programmed cell death)

• Vacuoles: storage sacs for water, nutrients, and waste (smaller and more numerous in animal cells.)

• Mitochondria:

• Structure: two parts; a folded inner membrane called cristae and an enzyme packed fluid matrix

• Function: site of cellular respiration. Breaks down chemical energy stored in food to produce usable cellular energy in the form of ATP

3. Explain the structure of the cell membrane and how its structure allows it to control what goes in and out of the cell.

• The cell (plasma) membrane, known as phospholipid bilayer,  is a permeable barrier that controls what goes in and out of the cell to maintain homeostasis. The phospholipid bilayer has 2 layers with hydrophilic (likes water) heads and hydrophobic (dislikes water) tails. Carbohydrates are embedded throughout to provide structures. Proteins are embedded to aid in transporting nutrients and signals.

• Transport Control:

• Passes Easily: Small nonpolar, hydrophobic molecules, and water

• Cannot Pass Easily: Polar molecules (it must use the protein channels) and large molecules (must use vesicles)

4. Explain the importance of each macromolecule to the overall function of cells and thus the human body.

5. Distinguish between the following terms: DNA, chromosomes, and genes. Then explain their relationship to proteins

• DNA: Organizes into 46 chromosomes and thousands of genes to provide instructions for making proteins.

• Chromosomes: Coiled structures of DNA holding genes.

• Genes: Sections of chromosomes that get transcribed into mRNA, which leaves the nucleus to be translated into a protein

• Protein Synthesis Steps:
  1. DNA unzips to make a single-stranded copy of mRNA

2. tRNA transfers corresponding amino acids to the ribosome, bonding them into a polypeptide chain that folds into a functional protein

6. Explain the role of enzymes in biochemical reactions, including the importance of their specificity

•  Enzymes are proteins that act as biological catalysts to speed up reactions by lowering activation energy

• Enzymes are highly specific and only bind to matching substrates (reactants) at their active sites

• Environmental changes in pH or temperature alter the active site shape, meaning the enzyme can no longer function. Enzymes remain unchanged after reactions and can be reused|
  
  

7. List the levels of organization within an organism

• Organism > Organ System > Organ > Tissue > Cell
  
  

8. Summarize the process of the cell cycle in somatic (body) cells. Include the name of each subphase, and the critical importance of chromosome duplication prior to cell division

• Interphase: Cell spends most of its life here; DNA is doubled (1 –> X sister chromatids) preparing for division

• Mitosis: Cell begins to divide across Prophase, Metaphase, Anaphase Telophase (PMAT)

• Cytokinesis: Cytoplasm splits to form 2 identical daughter cells

• The importance of chromosome duplication prior to cell division ensures daughter cells are identical to the parent cell (unless a random mutation occurs)
  
  

9. Explain what is meant by the phrase “form dictates function” and why it will be an essential theme in this course

• “Form dictates function” means that how a cell, tissue, or organ is physically built (its structure) determines the specific job it can do (its function). The physical setup of any biological part directly controls how it works.

• This is an essential theme in A&P because every system in the human body is designed to carry out a specific role based on its structure. Understanding a structure's physical form makes it easier to predict and remember functions from organelles all the way to whole organ systems.