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Flashcards in Biology 5 Deck (57)
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What are all living things made of ?

Cells

1

What 5 things are in a human cell ?

Nucleus
Cytoplasm
Cell Membrane
Mitochondria
Ribosomes

2

What is inside the nucleus ?

Genetic information that controls the activities of a cell

3

What is cytoplasm ?

A gel like substance where most of the chemical reactions take place. Enzymes control these reactions

4

What is the job of the cell membrane ?

Holds the cell together, controlling what goes in and out

5

Where does respiration take place ?

In mitochondria

6

What does a ribosome make ?

Proteins

7

What three things are in plant cells and not in animal cells ?

Cell wall
Vacuole
Chloroplasts

8

Why do plants have cell walls ?

It supports the cell and strengthens it

9

What is vacuole ?

A weak solution of sugar and salts (cell sap)

10

Where does photosynthesis occur ?

In the chloroplasts, which contain chlorophyll

11

Name a single celled organism ?

Yeast

12

Give an example of a cell without a nucleus

Bacteria - their genetic information floats in the cytoplasm

13

What is diffusion ?

the SPREADING OUT of PARTICLES from an area of HIGH concentration to an area of LOW concentration

14

Where does diffusion happen and why ?

Solutions and gases because the particles are free to move about randomly

15

Describe how perfume diffuses through the air in a room

The perfume particles are in high concentration when sprayed but it then diffuses around the room as perfume particles are in low concentration there

16

How do cell membranes restrict what comes in and goes out of a cell ?

Dissolved substances can move in an out of cells by diffusion. However small molecules are the only ones that can fit in, so large molecules that are unwanted cannot get in

17

What is special about a palisade leaf cell ?

It has more chloroplasts for photosynthesis. They have a tall shape that increases surface area to absorb more CO2

18

What are red blood cells adapted to do ?

Carry oxygen

19

What is the shape of a red blood cell ? How does this benefit it ?

Concave - giving it a bigger surface area for absorbing oxygen

20

Other than its shape, name two adaptations of a red blood cell

•Packed with haemaglobin
•no nucleus so that there is more room for the haemaglobin

21

What cells are specialised for reproduction ?

Sperm and Egg cells

22

What is the main function of an egg cell ?

To carry DNA and contain huge food reserves to nourish a developing embryo

23

How does an egg make sure only one sperm fertilises it ?

It's membrane changes instantly

24

How does a sperm cell get the male DNA to the female ?

It has a long tail and streamlined head that helps it to swim to the egg, there's a lot of mitochondria to supply energy

25

What is the process by which cells become specialised ?

Differentiation

26

What do large multicellular organisms have ?

Organ systems

27

What do these different organ systems do ?

Exchange and transport materials

28

What is a tissue ?

A group of cells, that can include more than one type of cell, that carry out a specific function

29

What is an organ ?

A group of different tissues that work together to perform a certain function