Biology: (Cell biology)

Question 1

Define Eukaryotic cells

Answer 1

A complex cell, such as plant or animal cell

Eukaryotic cells contain their genetic material (DNA) in the nucleus.
In animal & plant cells

Question 2

Define Prokaryotic cells

Answer 2

A small simple cell e.g a bacterium

In Prokaryotic cells, the genetic material (DNA) is not in a nucleus.
In bacteria

Question 3

two differences in structure between prokaryotic & eukaryotic cells

Answer 3

eukaryotic have a nucleus proka don’t

eukaryotic have mitochondria proka don’t

Question 4

magnification formula

Answer 4

magnification = image size / real size

Question 5

name at least 3 specialised cells

Answer 5

sperm cells
nerve cells
muscle cells
root hair cells
phloem & xylem cells

Question 6

how are sperm & nerve cells specialised

Answer 6

sperm cells have a long tail and streamlined head

nerve cells are long to cover distance and they have branched connections to connect to other nerve cells

Question 7

Osmosis definition

Answer 7

the diffusion of water molecules through a partially permeable membrane, from a high concentration to a low concentration

Question 8

what are chromosomes ?

Answer 8

coiled up lengths of DNA molecules

Each carries a large number of genes

Question 9

KNOW THIS: body cells normally have two copies of each chromosome. one from mother another from father

Answer 9

do u know ;)

Question 10

whats mitosis ?

Answer 10

the stage of the cell cycle when the cell divides.

multicellular organisms use mitosis to grow or replace cells that’ve been damaged

Question 11

two ways embryonic stem cells could be used to cure diseases

Answer 11

it could make insulin producing cells for diabetes

make nerve cells for people paralysed by spinal injury

Question 12

KNOW THIS: Some opponents of stem cell research argue that it offends human dignity or harms or destroys human life. Proponents argue that easing suffering and disease promotes human dignity and happiness, and that destroying a blastocyst is not the same as taking a human life

Answer 12

do u know ;)

Question 13

magnification & resolution definition

Answer 13

magnification- enlarging the physical appearance or image of something.

resolution-the smallest change a measuring instrument can detect

Question 14

give one metabolic reaction in cells

Answer 14

respiration

Question 15

name two substances transported in the blood plasma

Answer 15

carbon dioxide, water, urea

Question 16

which two blood vessels carry deoxygenated blood

Answer 16

pulmonary artery, vena cava

Question 17

why is having more red blood cells an advantage to an athlete (3 marks)

Answer 17

more haemoglobin so more oxygen can be carried for more aerobic respiration of muscle cells

Question 18

compare the structure of an artery with the structure of a vein (3 marks)

Answer 18

arteries have a thicker layer of muscle tissue

arteries have a narrower lumen

arteries don’t have valves but veins do

Question 19

where in the plant stem is there a high concentration of dissolved sugars

Answer 19

the phloem

Question 20

What are the four chambers of the heart

Answer 20

Right atrium, right ventricle

Left atrium, left ventricle

Question 21

Why does the heart have valves

Answer 21

To make sure the blood flows in the right direction