Exam #1

Question 1

characteristics of living organisms

Answer 1

order
reproduction
growth & development
energy processing
regulation/homeostasis
response to stimuli/environment
evolutionary adaptation

Question 2

cell: basic unit of life

Answer 2

• smallest unit capable of life functions
  growth, metabolism, response to stimuli, reproduction
• higher levels of organization (tissues, organs) are built from cells
• only eukaryotic cells (like plants and animals) have a nucleus, while prokaryotic cells (like bacteria) do not

Question 3

understanding evolution

Answer 3

evolution is the process by which species change over time through adaptation and natural selection
- evolution does not mean species stay the same; it reflects ongoing change. this change is driven by natural factors, such as mutations, genetic drift and environmental pressures

Question 4

phylogenetic trees

Answer 4

phylogenetic trees represent the evolutionary relationships among species

Question 5

branch points

Answer 5

represent the most recent common ancestor of the species diverging from that point
shows how species are related through evolution

Question 6

sources of genetic variation

Answer 6

crucial for evolution and adaptation. Adaptations occur due to genetic variations and environmental pressures, not an organism’s needs
natural selection - environmental survival pressures, gene flow, genetic drift, mutation

Question 7

unifying themes of biology

Answer 7

important theme for diversity - evolution: explains the variety and complexity of life on earth

Question 8

the scientific method

Answer 8

a systematic approach to investigation and discovery in science
1. observation
2. question
3. hypothesis formation
4. prediction
5. experiment
6. interpretation/ data analysis
7. conclusion/ new questions

Question 9

prokaryotic cells

Answer 9

lack a nucleus and membrane-bound organelles; found in bacteria and archaea

Question 10

eukaryotic cells

Answer 10

have a nucleus and membrane-bound organelles found in plants, animals, fungi and protists

Question 11

prokaryotic & eukaryotic

Answer 11

have ribosomes and DNA

Question 12

protons

Answer 12

positively charges particles found in the nucleus

Question 13

neutrons

Answer 13

neutrally charged particles in the nucleus

Question 14

electrons

Answer 14

negatively charged particles orbiting the nucleus

Question 15

covalent bonds

Answer 15

form when atoms share electron pairs (strong bonds)

Question 16

polar covalent bonds

Answer 16

the shared electrons have an unequal distribution, which leads to partial positive and negative regions on the molecule

Question 17

non-polar covalent bonds

Answer 17

the shared electrons have an equal distribution

Question 18

ionic bonds

Answer 18

ions that attract each other because of opposite charges

Question 19

hydrogen bonds

Answer 19

bonds that occur between polar molecules (like water), contributing to properties like cohesion. The partial negative and partial positive charges on a molecule attract to each other

Question 20

strongest bonds

Answer 20

covalent bonds - —– ionic bonds —- hydrogen

Question 21

carbohydrates

Answer 21

used primarily for energy storage (glucose, starch)

Question 22

monosaccharides

Answer 22

simple sugars, like glucose (building blocks)

Question 23

polysaccharides

Answer 23

complex carbs like starch

Question 24

proteins

Answer 24

made up of amino acids; responsible for structure, function and regulation of body tissues and organs

Question 25

amino acids

Answer 25

20 different amino acids, some are hydrophobic, some are hydrophilic. they are the building blocks of proteins

Question 26

lipids

Answer 26

hydrophobic molecules, important for long-term energy storage and cell membrane structure (fats, oils) fatty acids - building blocks fats phospholipids steroids

Question 27

Nucleic Acids: DNA stores genetic information and RNA transmits genetic information for protein synthesis

Answer 27

DNA base pairs: A-T, C-G RNA base pairs: A-U, C-G

Question 28

Hydrophobic

Answer 28

molecules that repel water (lipids, fatty acids)

Question 29

Hydrophilic

Answer 29

molecules that attract water (glucose, salts)

Question 30

building blocks

Answer 30

mono - single building block di - two tri - three poly - many

Question 31

primary protein structure

Answer 31

the sequence of amino acids in polypeptide chain

Question 32

secondary structure

Answer 32

alpha-helices and beta-sheets formed by hydrogen bonds between amino and carboxyl regions of the amino acids

Question 33

tertiary structure

Answer 33

the interactions between the amino acid side chain facilitate 3D structure

Question 34

quaternary structure

Answer 34

multiple folded proteins come together to make a functional protein

Question 35

amino acids

Answer 35

the building blocks (monomers) of proteins, linked together by peptide bonds

Question 36

DNA (deoxyribonucleic Acid)

Answer 36

stores genetic information and is responsible for inheritance

Question 37

RNA (Ribonucleic Acid)

Answer 37

involved in protein synthesis and gene regulation

Question 38

transcription

Answer 38

the process of making RNA from DNA occurs in the nucleus mRNA - capped, tailed, spliced, it is transported to the cytoplasm to be translated

Question 39

RNA polymerase

Answer 39

transcription the enzyme responsible for adding RNA nucleotides and transcribing the DNA into RNA

Question 40

Transcription factors

Answer 40

proteins that help initiate transcription by recruiting RNA polymerase to the promoter region

Question 41

mRNA processing

Answer 41

cap and tail: added to protect mRNA from degradation splicing: removal of introns (non-coding sequences) and joining of exons (coding sequences)

Question 42

translation

Answer 42

the process of synthesizing a polypeptide chain (protein) mRNA. Involves ribosomes, tRNA and mRNA

Question 43

ribosomes

Answer 43

translation organelles that carry out protein synthesis

Question 44

codons

Answer 44

translation three-nucleotide sequences in mRNA that code for amino acids

Question 45

start codon

Answer 45

translation AUG (signals the start)

Question 46

stop codons

Answer 46

trigger the release factor to bind the ribosome and stops translation

Question 47

tRNA

Answer 47

carries amino acids to the ribosome for incorporation into the growing polypeptide chain