Lecture 1: Cell Biology

Question 1

What does dna stand for?

Answer 1

Deoxyribonucleic acid

Question 2

How does info get from the dna to the rest of the cell?

Answer 2

The DNA sequence encodes genes, genes encode proteins and the proteins go through a process of transcription and translation of DNA

Question 3

What process in DNA Replication occurs first?

Answer 3

Transcription occurs first and is then followed by the process of translation.

Question 4

What is the process of transcription?

Answer 4

This is the first step of gene expression and is the process of copying a segment of DNA into RNA. The segment of DNA is then transcribed into RNA molecules.

Question 5

What is the process of translation?

Answer 5

The process in which ribosomes in the cytoplasm or ER are synthesised. The mRNA is decoded in a ribosome to produce a specific amino acid chain.

Question 6

What are some features of a prokaryotic cell?

Answer 6

Smaller in size, no organelles, naked DNA in cytoplasm

Question 7

What are some features of a eukaryotic cell?

Answer 7

Large, complex, internal structure with organelles, membrane-bounded nucleus containing DNA.

Question 8

What are some features of a cell membrane?

Answer 8

Cell membranes are made up of lipid bilayers and also contain hydrophilic heads on outer and inner membrane, whereas there are hydrophobic tails in the middle of the membrane. The cell membrane is also semi-permeable as it allows nutrients, wastes, proteins and ions to pass in and out of the cell.

Question 9

What are the processes in which energy and matter flow from one organism to another?

Answer 9

The processes of respiration and photosynthesis.

Question 10

What is a key form of energy in the cell?

Answer 10

ATP is a key form of energy in the cell, and is created by breaking down nutrients and energy converted to ATP.

Question 11

What are some unique features in a plant cell?

Answer 11

Chloroplasts and Cell Wall

Question 12

What is the nucleus and its purpose?

Answer 12

Nucleus is the location of the DNA and the cells heritable material and is surrounded by a double nuclear membrane

Question 13

What is nucleolus?

Answer 13

The site where ribosome units are assembled and genetic information is synthesised and translated into language of proteins.

Question 14

What are ribosomes, where are they located in the cell and what is their purpose?

Answer 14

Ribosomes perform protein synthesis in both prokaryotes and eukaryotes. They read mRNA and produce encoded protein via process of translation. Ribosomes are free in the cytoplasm and also attached to the rough endoplasmic reticulum.

Question 15

What is the rough endoplasmic reticulum and its purpose?

Answer 15

The rough endoplasmic reticulum has ribosomes attached thus has a rough surface and is a major organelle for protein synthesis.

Question 16

What are mitochondria?

Answer 16

Mitochondria is the respiratory centre of the cell and harvests energy from food molecules. Mitochondria has its own DNA and ribosomes that make its own proteins.

Question 17

What is the process of cellular respiration?

Answer 17

Glucose + Oxygen = Carbon Dioxide + Water + ATP (energy)

Question 18

What is chloroplast and what is its purpose?

Answer 18

Chloroplasts is the photosynthesis centre of the cell. It is a type of organelle called a plastid and found only in plant cells, containing pigment, chlorophyll.

Question 19

What membranes are in chloroplasts?

Answer 19

Outer, inner and thylakoid membranes.

Question 20

What is the cytoskeleton of cells?

Answer 20

It is the source of shape and structure of the cell and is correlated with the evolution of mitosis and is essential for eukaryotic cell division.

Question 21

What are the three different types of cytoskeletons?

Answer 21

The microtubules, intermediate filaments and microfilaments.

Question 22

What is the vacuole and purpose?

Answer 22

The vacuole is referred to as the plant cell regulator and mature plant cells have one or more vacuoles that typically occupy more than 30% of the volume. The vacuole houses water that contains enzymes, ions, pigments and toxic metabolic byproducts.

Question 23

What are extracellular structures and what are some distinguishing features of this cell feature?

Answer 23

A cell wall in plants and fungi. Some distinguishing features include rigid structure outside of plasma and it is consisting of polysaccharides as well as limiting cellular expansion but prohibits shape change.

Question 24

What is a prokaryotic cell?

Answer 24

A prokaryotic cell is a single chamber where all processes occur in the same place. A prokaryotic chromosome is a single, circular molecule.

Question 25

What are eukaryotic cells?

Answer 25

They are large cells and have a complex internal structure. They contain organelles, membrane bounded nucleus which contains DNA.

Question 26

What is the cell membrane consisted of?

Answer 26

The cell membrane is made up of lipid bilayers, which have hydrophilic heads on the outer edge and inner edges of membrane. The hydrophobic tails face in the middle of the membrane.

Question 27

What is an important role of the cell membrane?

Answer 27

The cell membrane is semi-permaeable, therefore, various nutrients, wastes, proteins and ions can pass in and out of the cell.

Question 28

What is the main form of energy in the cell?

Answer 28

The main form of energy in the cell is ATP (adenosine triphosphate).

Question 29

How can ATP be used in the cell?

Answer 29

After breaking down nutrients, energy is convereted to ATP. When ATP is broken down, to adenosine disphosphate, this energy can be released and used.

Question 30

Compare prokarytic and eukaryotic cells?

Answer 30

Eukaryotes have internal membrane structure to form organelles, whereas prokaryotes do not have membrane bounded organelles like mitochondria, chloroplasts, ER, and nucleus.