Question
Explain primary and secondary sexual characteristics in humans with examples.
✓
Answer
The traits that separate male from females are called primary and secondary sexual characteristics. Primary sexual characteristics are those which are present by birth and are determined by chromosomes whereas secondary sexual characteristics are those which distinguishes sexually mature male from female.
|
Primary sexual characteristics
|
Secondary sexual characteristics
|
|
Penis and scrotum growth.
|
Facial hairs.
|
|
Ovary, uterus, vagina, clitoris and labia growth.
|
Enlarged breats and hips.
|
|
|
Hair and sweat gland changes.
|
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
Observe the Fig and answer the following questions:
$a.$ Name the microorganism and the group to which it belongs.
$b.$ Name the food item on which the organism grows.
$c.$ Does it grow well in dry or in moist conditions?
$d.$ Is it safe to eat infected bread?
→$a.$ Name the microorganism and the group to which it belongs.
$b.$ Name the food item on which the organism grows.
$c.$ Does it grow well in dry or in moist conditions?
$d.$ Is it safe to eat infected bread?
The fossil fuel $P$ is formed under the earth by the decomposition of vegetable matter lying under water by the action of anaerobic bacteria. The major component of fuel $P$ is $Q$. The fossil fuel $P$ is used as a source of gas $R$ needed to manufacture nitrogenous fertilisers. When $P$ is filled in metal cylinders and used as a fuel in motor vehicles, it is called $S$. What are $P, Q, R$ and $S$?
→State five uses of metals and five uses of non$-$metals.
→Fill in the banks. Fossil fuels are ________, ________ and _________.
Name the hormone which would be released during the following situations:
$a.$ A frightened person.
$b.$ Growth of a child to adult.
$d.$ Development of caterpillar to moth.
$d.$ Development of tadpole to frog.
→$a.$ A frightened person.
$b.$ Growth of a child to adult.
$d.$ Development of caterpillar to moth.
$d.$ Development of tadpole to frog.
What kind of friction comes into play:
$a.$ When a block of wood kept on table moves slowly?
$b.$ When a block of wood kept on table just tends to move (or slip)?
$c.$ When a block of wood kept on cylindrical iron rods moves?
→$a.$ When a block of wood kept on table moves slowly?
$b.$ When a block of wood kept on table just tends to move (or slip)?
$c.$ When a block of wood kept on cylindrical iron rods moves?
Given below are certain food items required for proper nourishment of adolescents. Name the nutrients present in the food items and write their functions.
→|
S.No
|
Food items
|
Major Nutrient
|
Functions
|
|
$1.$
|
Pulses and nuts
|
|
|
|
$2.$
|
Oranges and Amla
|
|
|
|
$3.$
|
Sugar, Roti
|
|
|
|
$4.$
|
Oils
|
|
|
|
$5.$
|
Vegetables
|
|
Explain food preservatives with examples.
Describe cloning with diagram.
The part of $P$ and $Q$ are present only in plant cells, and they are not present in animal cells. The part $P$ contains a green pigment called $R$ whereas part $Q$ is made of a tough material $S$. The part $P$ takes part in the food making process whereas part $Q$ gives shape and support to the plant cell.
$a.$ What is $(i) P$, and $(ii) Q?$
$b.$ What is $(i) R$, and $(ii) S?$
→$a.$ What is $(i) P$, and $(ii) Q?$
$b.$ What is $(i) R$, and $(ii) S?$