Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > B1 > Flashcards

B1 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What are eukaryotes?

A

All animals and plants, made from complex cells called eukaryotic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are prokaryotes?

A

Bacteria, simple cells called prokaryotic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is in the nucleus?

A

DNA in the form of chromosomes that controls the cell’s activities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is cytoplasm?

A

Gel-like substance where most chemical reactions happen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the mitochondria?

A

The site of cellular respiration and contain enzymes needed for reactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the cell membrane?

A

Holds the cell together and controls what goes in and out by providing a selective barrier. Also contain receptor molecules that are used for cell communication

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is a cell wall?

A

Made of cellulose, gives support to a plant cell (exclusively plant cells)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are chloroplasts?

A

It’s where photosynthesis occurs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is chromosomal DNA within a prokaryotic cell?

A

It controls the cell’s activities and replication. It floats freely in the cytoplasm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are plasmids within a prokaryotic cell?

A

Small loops of extra DNA that aren’t part of the chromosome. Plasmids contain genes for things such as drug resistance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

When were light microscopes invented and what do they do?

A

In the 1590s. They let us see things like nuclei and chloroplasts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When were electron microscopes invented and what do they do?

A

In the 1930s. They let us see much smaller things in more detail like the internal structure of mitochondria. This has allowed us to have a much greater understanding of sub-cellular structures.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What do transmission electron microscopes do?

A

They have a higher magnification and resolution than light microscopes but they aren’t portable. They’re expensive, and it is a complicated process to prepare specimens for use.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the different parts of a microscope?

A

The eyepiece lens (looked through to see + magnify image), objective lens (magnifies image eg. x4, x10 and x40), stage, clip, handle, lamp and focusing knobs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do you calculate magnification?

A

Eyepiece lens magnification x Objective lens magnification OR Image Size/Real Size

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is DNA?

A

It contains all of an organism’s genetic material - the chemical instructions it needs to grow and develop. DNA is arranged into chromosomes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are chromosomes?

A

They are long molecules of coiled up DNA. The DNA is divided into short sections called genes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a double helix?

A

DNA is a double helix (a double-stranded spiral). Each of the two DNA strands is made up of lots of nucleotides joined together in a long chain. Nucleotides each contain a small molecule called a “base”. The bases are A, C, G and T. Each base forms cross links to a base on the other strand, keeping the two DNA strands tightly wound together. DNA is a polymer.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is complementary base pairing?

A

A always pairs up with T, and C always pairs up with G.

20
Q

What do nucleotides contain?

A

Each nucleotide has the same sugar and a phosphate group. The base on each nucleotide is the only part of the molecule that varies. The base is attached to the sugar.

21
Q

How is DNA a polymer?

A

Polymers are large, complex molecules composed of long chains of monomers joined together. DNA is a polymer made up of nucleotide monomers.

22
Q

What does DNA control?

A

Protein synthesis. A section of DNA that codes for a particular protein is called a gene. Proteins are made up of chains of amino acids - each different protein is made up of a different number and order of amino acids.

23
Q

How does protein synthesis work?

A

DNA contains the gene coding for a protein. The two DNA strands unzip around the gene and used as a template to make mRNA. Base pairing ensure it’s complementary (matches the opposite strand) - this is known as transcription. The mRNA leaves the nucleus and goes to the cytoplasm, where amino acids which match the triplet codes on the mRNA are joined together in the correct order - this is known as translation.

24
Q

What are enzymes?

A

They control cell reactions. They are produced by living things and act as biological catalysts (a substance which speeds up a reaction).

25
Q

What is a substrate?

A

It changes in a reaction with an enzyme. Every enzyme has an active site - the part where it joins on to its substrate to catalyse the reaction. Enzymes usually only work with one substrate - they have a high specificity.

26
Q

What is “lock and key”?

A

A substrate fitting with an enzyme like a key fits into a lock.

27
Q

What happens if an enzyme becomes too hot?

A

Some of the bonds holding the enzyme together break - this makes the enzyme become denatured and it loses its shit. This means that the subsrate doesn’t fit the active site anymore, meaning that the enzymes can’t catalyse a reaction and the reaction stops. This is IRREVERSIBLE.

28
Q

How does pH affect an enzyme?

A

If the pH is too high or low, it interferes with the bonds holding the enzyme together. This can irreversibly denature the enzyme. Enzymes mostly have an optimum pH of 7.

29
Q

How does enzyme/substrate concentration affect the rate of reaction?

A

As the enzyme/substrate concentration rises, the rate of reaction also increases. However, at a certain point, there are too many of one molecule and not enough of the other to reach with and so adding more makes no difference.

30
Q

What is respiration?

A

The process of transferring energy from the breakdown of glucose. It occurs in every cell in all living things. The energy transferred by respiration can’t be used directly, so it’s used to make a substance called ATP. ATP stores the energy needed for many cell processes.

31
Q

What is respiration controlled by?

A

Enzymes - the rate of respiration is affected by both temperature and pH. It’s an exothermic reaction - it transfers energy to the environment.

32
Q

What is aerobic respiration?

A

Aerobic - “with oxygen” - it’s what happens when lots of oxygen is available. It’s the most efficient way to transfer energy from glucose. The equation for this is Glucose + Oxygen -> Carbon Dioxide + Water

33
Q

What is the chemical equation for aerobic respiration?

A

C6H12O6 + 6O2 -> 6CO2 + 6H2O

34
Q

What is anaerobic respiration?

A

Anaerobic - “without oxygen” - it’s not the best way to transfer energy from glucose as it transfers much less energy per glucose molecule than aerobic.

35
Q

Why does anaerobic respiration happen?

A

When you do really vigorous exercise, your body can’t supply enough oxygen to the muscles for aerobic respiration. This means that the muscles start to respire anaerobically - the glucose is only partially broken down, and lactic acid is produced. Lactic acid causes fatigue in the muscles, and after anaerobic respiration + stopping exercise you would have oxygen debt.

36
Q

What is oxygen debt?

A

You need extra oxygen to break down all the lactic acid that’s built up to allow aerobic respiration to begin again.

37
Q

What is the equation for anaerobic respiration in plants?

A

Glucose -> Ethanol + Carbon Dioxide

38
Q

What are carbohydrates made up of?

A

Simple sugars - eg. glucose. These can join together in long chains, polymers, to make complex carbohydrates - eg. starch or glycogen. The polymer molecules can break down back into sugars - they are broken down by enzymes in the mouth and small intestine.

39
Q

What are proteins made up of?

A

Amino acids - they are polymers made of long chains of amino acids. Amino acids contain carbon, nitrogen, hydrogen and oxygen atoms. Proteins are broken down by enzymes in the stomach and small intestine.

40
Q

What are lipids made up of?

A

They are fats and oils made from glycerol and three fatty acids. They aren’t polymers because they don’t form long chains of repeating units. Lipids contain carbon, hydrogen and oxygen atoms. They are broken down by enzymes in the small intestine.

41
Q

How do you test for the different biological molecules?

A

Proteins - Biuret test (colour changes purple)

42
Q

What is photosynthesis?

A

Plants are able to make their own food (glucose) from the sun’s energy through photosynthesis. It happens inside chloroplasts - they contain chlorophyll which absorb light needed for photosynthesis.

43
Q

What is the word + chemical equation for photosynthesis?

A

6CO2 + 6H2O -> C6H12O6 + 6O2

44
Q

What are the three factors which affect the rate of photosynthesis?

A

Light intensity, concentration of CO2 and temperature

45
Q

How does light affect photosynthesis?

A

Light transfers energy needed for photosynthesis. As the light level is raised, the rate of photosynthesis increases steadily - but only up to a certain point. Beyond that point, it’ll be either temperature or CO2 level which is the limiting factor.

46
Q

How does CO2 affect photosynthesis?

A

CO2 is one of the raw materials needed for photosynthesis. As with light intensity the concentration of CO2 only increases the rate of photosynthesis to a certain poitn.

47
Q

How does temperature affect photosynthesis?

A

It has to be just right - if the temperature is the limiting factor, it’s because it’s too low - the enzymes needed for photosynthesis work more slowly at low temperatures. But if it gets too hot, the enzymes needed would denature.

Biology (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions