Chapter 4: Intro to Eukaryotic Cells

Besides the presence of 70S ribosomes in chloroplasts and mitochondria, the presence of which organic molecule in eukaryotes is similar in shape to the molecule in bacteria?

circular DNA

Eukaryotic characteristics:

organism - unicellular protists and yeasts, multicellular animals, plants, and fungi

cell division - asexual(mitosis), sexual(meiosis)

nucleus - yes

ribosomes - 80S: cytoplasm, rough, endoplasmic reticulum, 70S: mitochondria and chloroplasts

chromosomes - multiple linear chromosomes

membrane bound organelles - yes

Prokaryotic characteristics:

organism - unicellular archaea and bacteria

cell division - asexual(binary fission)

nucleus - no

ribosomes - 70S only

chromosomes - usually a single circular chromosome

membrane bound organelles - no(but may have membranous inclusion)

Why doesn’t penicillin kill eukaryotic cells?

eukaryotic cells dont make peptidoglycan which is what penicillin targets

What two eukaryotic organelles divide using a process similar to binary fission?

mitochondria and chloroplasts

What is the difference between endocytosis and exocytosis?

endocytosis - import things into the cell

exocytosis - remove things from the cell

Are endocytosis and exocytosis active or passive processes?

active process

What is the difference between pinocytosis and phagocytosis?

pinocytosis - cell drinking, endocytosis of dissolved substances in small vesicles, nonspecific mass transport for cell survival

phagocytosis - cell eating, endocytosis of undissolved substances, engulf whole cells or viruses

What is a phagocyte and what is its function?

specialized immune cells that engulf and destroy their targets

Name four eukaryotic kingdoms

animalia, plantae, fungi, protista

Name two phyla of parasitic helminths

roundworms and flatworms

What are unicellular fungi called?

yeasts

Fungi are saprobes. What does this mean?

absorb nutrients from dead plants and animals in the environment

What are dimorphic fungi?

fungi that cycle between having hyphae and living as a yeast like form, having two forms

Define mycoses

diseases that are caused by fungi

Vaginal yeast infections are mainly caused by which genus of yeast

Candida

What is a dermatophyte?

a collection of fungal pathogens that infect the skin, hair, and nails, break down the protein keratin in these structures

One common dermatophytic infection is called tinea. What are two common names for tinea infections?

ringworm and athlete’s foot

Some eukaryotes have cell walls. Where is it located compared to the organism’s plasma membrane?

external to the plasma membrane

Do animal cells have cell walls?

no

How does the motion produced by eukaryotic flagella differ from prokaryotic flagella?

pro have a rotary motion

euk have wave like back and forth motion

Do prokaryotes possess cilia?

no

What two areas within a cell are eukaryotic ribosomes located?

can be free in the cytoplasm or bound to the membrane of the endoplasmic reticulum

Do eukaryotic cells possess 70S ribosomes as well as 80S ribosomes?

yes

What are the two main functions of the cytoskeleton?

shapes cells and coordinates cell cargo movement

What is the main macromolecule housed in the nucleus?

DNA

What occurs in the nucleolus of a eukaryotic cell?

site where ribosomal subunits begin their development

What is the function of rough endoplasmic reticulum (RER)?

essential in protein production, quality control manager

What structures make RER rough?

millions of ribosomes on the outer surface

What is the main function of smooth endoplasmic reticulum?

tends to be more involved in lipid production, detox substances like drugs, alcohol, and various metabolic byproducts

What is the function of the Golgi apparatus?

coordinates with ER to modify cellular proteins, build lipids, and further sort and distribute the finished products

What is the function of lysosomes?

contain wide variety of hydrolytic enzymes that break down substances engulfed by the cell during phagocytosis and receptor-mediated endocytosis, remove damaged organelles and other defunct cell components

What is the function of peroxisomes?

contain enzymes that break down certain fats and amino acids and protect the cell from hydrogen peroxide and other toxic oxygen intermediates

What is the main function of mitochondria?

make most of the cell’s adenosine triphosphate(ATP)

What is the relationship between the number of mitochondria per cell and the activity level of the cell?

more mitochondria equals higher activity level of the cell

What is the function of chloroplasts?

allow the cells to harvest energy from sunlight