review - exam 1

Question 1

polymers found in insects

Answer 1

chitin & glycogen

Question 1

monomers connected together via dehydration synthesis to make cellulose, glycogen, & starch

Answer 1

glucose

Question 2

what role do enzymes play in in building & breaking down macromolecules

Answer 2

enzymes act as catalysts that increase the rate of reaction to build up or break down macromolecules

Question 3

alpha-helix vs beta-sheet structure in proteins

Answer 3

both are an example of secondary structure

both may be present in globular proteins

the structure of both are maintained by hydrogen bonding

Question 4

what type of bond holds the amino acid together

Answer 4

peptide

Question 5

hydrophobic exclusion

Answer 5

hydrophobic molecules tend to stick together in water to avoid contact

Question 6

what is the relationship between a gene & a protein?

Answer 6

protein coding genes contain the info to make a protein

Question 7

why is transcription necessary

Answer 7

it makes an RNA copy of the gene

RNA can leave the nucleus & be used in translation

Question 8

mRNA

Answer 8

messenger

carries info used to make proteins

has codons

Question 9

tRNA

Answer 9

transfer

used in translation

connects codons & amino acids

Question 10

rRNA

Answer 10

ribosomal

makes up part of ribosomal structure

Question 11

snRNA

Answer 11

small nuclear

involved in RNA splicing

Question 12

which direction is RNA transcribed

Answer 12

5’ - 3’

AWAY from the promoter

Question 13

explain how eukaryotic mRNAs get out of the nucleus

Answer 13

through nuclear pores

polyA binding proteins bind to tail

binding proteins have nuclear export signals which direct the binding proteins & mRNA out of cell

Question 14

what is alt RNA splicing

Answer 14

in different cells & conditions pre-mRNA can be interpreted differently

1 gene –> 1 pre-mRNA –> multiple mature mRNAs –> multiple proteins

Question 15

how to increase membrane fluidity

Answer 15

more unsaturated fatty acids

shorter tails

less proteins

more cholesterol

Question 16

what types of molecules can easily move across a phospholipid bilayer

Answer 16

steroids, hormones, & gases

Question 17

what types of molecules have DIFFICULTY passing the bilayer

Answer 17

ions & large molecules

Question 18

example of substance moved by simple diffusion

Answer 18

hormone

Question 19

example of substance moved by facilitated diffusion

Answer 19

ions

Question 20

example of substance moved by active transport

Answer 20

ions

Question 21

osmosis

Answer 21

sometimes proteins (for rapid)

energy needed

movement down concentration gradient

example = water

Question 22

explain how cholesterol enters your cells

Answer 22

apo protein on LDL complexes binds to LDL receptors on the plasma membrane

cell brings in the LDL by receptor-mediated endocytosis

LDL can be broken down & LDL receptors are recycled back into membrane

Question 23

what structures make up the endomembrane system

Answer 23

transport vesicle

lysosome

golgi apparatus

rough & smooth er

plasma membrane

Question 24

lysosome

Answer 24

molecules broken down by hydrolysis

part of endomembrane system

Question 25

peroxisome

Answer 25

molecules broken down by oxidation

Question 26

lines of evidence that support the theory that mitochondria & chloroplasts were once free living prokaryotic cells

Answer 26

same size as avg pro cell

have double membranes

have ribosomes

circular chromosomes

divide by the same mechanism as bacteria

Question 27

what produces Okazaki fragments

Answer 27

DNA Pol III

Question 28

what stabilizes the replication bubble

Answer 28

single stranded binding proteins