(LE 1) Cell Structure & Genetic Control

Question 1

What is a cell?

Answer 1

Basic unit of structure and function in the body

Question 2

What are the three common characteristics of a typical human cell?

Answer 2

• plasma membrane
• nucleus (not all mature cells)
• cytoplasm

Question 3

What is an organelle?

Answer 3

cytoplasmic structures that perform specialized functions for the cell

Question 4

What is the structure and function of the plasma membrane?

Answer 4

Phospholipid bilayer; barrier between intracellular and extracellular environments

Question 5

What is the function of integral proteins and peripheral proteins?

Answer 5

Integral (transmembrane) protein: interact with fatty acid tail. Span across entire membrane

Peripheral protein: embedded on just one side of the membrane

function:
- structural support
- transport
- enzymatic control of cell processes
- receptor for hormones and other molecules
- self markers for immune system

Question 6

What is bulk transport?

Answer 6

Way cells move large molecules and particles across PM

Question 7

What type of bulk transport is pictured?

Answer 7

phagocytosis

Question 8

What type of bulk transport is pictured?

Answer 8

Receptor mediated endocytosis (more specific)

Question 9

What type of bulk transport is pictured?

Answer 9

Pinocytosis - cell drinking (non-specific)

Question 10

What type of bulk transport is pictured? What specific organelle helps to facilitate it?

Answer 10

Exocytosis - exports products into extracellular fluid
- secretory-vesicles

Question 11

What is a cytoskeleton?

Answer 11

latticework of microfilaments and microtubules filling cytoplasm
- gives cell structure
- form tracks to transport products around cell

Question 12

What are lysosomes?

Answer 12

organelles containing digestive enzymes and digested matter

Question 13

What are peroxisomes?

Answer 13

organelles containing oxidative enzymes
- involved in liver detoxification
- break down H2O2

Question 14

What is an endoplasmic reticulum?

Answer 14

system of membranes specialized for synthesis or degradation of molecules

Question 15

What is a rough ER?

Answer 15

contains ribosomes for protein synthesis

Question 16

What is a smooth ER?

Answer 16

contains enzymes for steroid synthesis and inactivation

Question 17

What is the golgi apparatus?

Answer 17

• lysosomes and secretory vesicles are formed here

Question 18

Where is RNA made and stored in the cell?

Answer 18

Nucleolus

Question 19

What is a chromatin?

Answer 19

DNA combined with protein creating a threadlike material that makes up chromosomes

Question 20

What is a euchromatin?

Answer 20

part of chromosomes active in transcription

Question 21

What is a heterochromatin?

Answer 21

highly condensed region where genes are permanently inactivated

Question 22

What are genes?

Answer 22

lengths of DNA that code for proteins

Question 23

What is gene expression?

Answer 23

process where Genes in our DNA are converted into a protein

Question 24

What is transcription?

Answer 24

occurs when DNA sequence in a gene is turned into an mRNA sequence. (Happens in nucleus)

Question 25

What is translation?

Answer 25

occurs when mRNA sequence is used to make a protein. Occurs in the cytoplasm

Question 26

How does tRNA function?

Answer 26

carries amino acid to ribosome. if anticodon on tRNA matches codon on mRNA it adds it to polypeptide chain

Question 27

What is Pre-mRNA?

Answer 27

RNA strand created from template DNA strand prior to removal of introns and extron splicing

Question 28

What are introns and extrons?

Answer 28

introns: contain non-coding regions
extrons: contain coding regions

exons spliced together after introns are removed to form mRNA

Question 29

How can a given gene produce several mRNA combinations?

Answer 29

alternative splicing of exons

Question 30

What is an anticodon?

Answer 30

Region of tRNA that contains the complementary sequence to a specific mRNA codon